This manual documents how to install and use the Multiple Precision Floating-Point Reliable Library, version 2.3.0.

Copyright 1991, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007 Free Software Foundation, Inc.

Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.1 or any later version published by the Free Software Foundation; with no Invariant Sections, with the Front-Cover Texts being “A GNU Manual”, and with the Back-Cover Texts being “You have freedom to copy and modify this GNU Manual, like GNU software”. A copy of the license is included in GNU Free Documentation License.

This library is free; this means that everyone is free to use it and free to redistribute it on a free basis. The library is not in the public domain; it is copyrighted and there are restrictions on its distribution, but these restrictions are designed to permit everything that a good cooperating citizen would want to do. What is not allowed is to try to prevent others from further sharing any version of this library that they might get from you.

Specifically, we want to make sure that you have the right to give away copies of the library, that you receive source code or else can get it if you want it, that you can change this library or use pieces of it in new free programs, and that you know you can do these things.

To make sure that everyone has such rights, we have to forbid you to deprive anyone else of these rights. For example, if you distribute copies of the MPFR library, you must give the recipients all the rights that you have. You must make sure that they, too, receive or can get the source code. And you must tell them their rights.

Also, for our own protection, we must make certain that everyone finds out that there is no warranty for the MPFR library. If it is modified by someone else and passed on, we want their recipients to know that what they have is not what we distributed, so that any problems introduced by others will not reflect on our reputation.

The precise conditions of the license for the MPFR library are found in the Lesser General Public License that accompanies the source code. See the file COPYING.LIB.

MPFR is a portable library written in C for arbitrary precision arithmetic
on floating-point numbers. It is based on the GNU MP library.
It aims to extend the class of floating-point numbers provided by the
GNU MP library by a precise semantics. The main differences
with the `mpf`

class from GNU MP are:

- the
`mpfr`

code is portable, i.e. the result of any operation does not depend (or should not) on the machine word size`mp_bits_per_limb`

(32 or 64 on most machines); - the precision in bits can be set exactly to any valid value for each variable (including very small precision);
`mpfr`

provides the four rounding modes from the IEEE 754-1985 standard.

In particular, with a precision of 53 bits, `mpfr`

should be able
to exactly reproduce all computations with double-precision machine
floating-point
numbers (`double`

type in C), except the default exponent range
is much wider and subnormal numbers are not implemented but can be emulated.

This version of MPFR is released under the GNU Lesser General Public License. It is permitted to link MPFR to non-free programs, as long as when distributing them the MPFR source code and a means to re-link with a modified MPFR library is provided.

Everyone should read MPFR Basics. If you need to install the library yourself, you need to read Installing MPFR, too.

The rest of the manual can be used for later reference, although it is probably a good idea to glance through it.

Here are the steps needed to install the library on Unix systems
(more details are provided in the `INSTALL` file):

- To build MPFR, you first have to install GNU MP
(version 4.1 or higher) on your computer.
You need a C compiler, preferably GCC, but any reasonable compiler should
work. And you need a standard Unix `
`make`' program, plus some other standard Unix utility programs. - In the MPFR build directory, type
`
`./configure`'This will prepare the build and setup the options according to your system. If you get error messages, you might check that you use the same compiler and compile options as for GNU MP (see the

`INSTALL`file). - `
`make`'This will compile MPFR, and create a library archive file

`libmpfr.a`. A dynamic library may be produced too (see configure). - `
`make check`'This will make sure MPFR was built correctly. If you get error messages, please report this to `

`mpfr@loria.fr`'. (See Reporting Bugs, for information on what to include in useful bug reports.) - `
`make install`'This will copy the files

`mpfr.h`and`mpf2mpfr.h`to the directory`/usr/local/include`, the file`libmpfr.a`to the directory`/usr/local/lib`, and the file`mpfr.info`to the directory`/usr/local/share/info`(or if you passed the ``--prefix`' option to`configure`, using the prefix directory given as argument to ``--prefix`' instead of`/usr/local`).

There are some other useful make targets:

- `
`mpfr.info`' or ``info`'Create an info version of the manual, in

`mpfr.info`. - `
`mpfr.dvi`' or ``dvi`'Create a DVI version of the manual, in

`mpfr.dvi`. - `
`mpfr.ps`'Create a Postscript version of the manual, in

`mpfr.ps`. - `
`clean`'Delete all object files and archive files, but not the configuration files.

- `
`distclean`'Delete all files not included in the distribution.

- `
`uninstall`'Delete all files copied by `

`make install`'.

MPFR suffers from all bugs from the GNU MP library, plus many more.

Please report other problems to ``mpfr@loria.fr`'.
See Reporting Bugs.
Some bug fixes are available on the MPFR web page
http://www.mpfr.org/.

The latest version of MPFR is available from http://www.mpfr.org/.

If you think you have found a bug in the MPFR library, first have a look on the MPFR web page http://www.mpfr.org/: perhaps this bug is already known, in which case you may find there a workaround for it. Otherwise, please investigate and report it. We have made this library available to you, and it is not to ask too much from you, to ask you to report the bugs that you find.

There are a few things you should think about when you put your bug report together.

You have to send us a test case that makes it possible for us to reproduce the bug. Include instructions on how to run the test case.

You also have to explain what is wrong; if you get a crash, or if the results printed are incorrect and in that case, in what way.

Please include compiler version information in your bug report. This can
be extracted using ``cc -V`' on some machines, or, if you're using gcc,
``gcc -v`'. Also, include the output from ``uname -a`' and the MPFR
version (the GMP version may be useful too).

If your bug report is good, we will do our best to help you to get a corrected version of the library; if the bug report is poor, we won't do anything about it (aside of chiding you to send better bug reports).

Send your bug report to: ``mpfr@loria.fr`'.

If you think something in this manual is unclear, or downright incorrect, or if the language needs to be improved, please send a note to the same address.

All declarations needed to use MPFR are collected in the include file
`mpfr.h`. It is designed to work with both C and C++ compilers.
You should include that file in any program using the MPFR library:

#include <mpfr.h>

A floating-point number or float for short, is an arbitrary
precision mantissa with a limited precision exponent. The C data type
for such objects is `mpfr_t`

(internally defined as a one-element
array of a structure, and `mpfr_ptr`

is the C data type representing
a pointer to this structure). A floating-point number can have
three special values: Not-a-Number (NaN) or plus or minus Infinity. NaN
represents an uninitialized object, the result of an invalid operation
(like 0 divided by 0), or a value that cannot be determined (like
+Infinity minus +Infinity). Moreover, like in the IEEE 754-1985 standard,
zero is signed, i.e. there are both +0 and −0; the behavior
is the same as in the IEEE 754-1985 standard and it is generalized to
the other functions supported by MPFR.

The precision is the number of bits used to represent the mantissa
of a floating-point number;
the corresponding C data type is `mp_prec_t`

.
The precision can be any integer between `MPFR_PREC_MIN`

and
`MPFR_PREC_MAX`

. In the current implementation, `MPFR_PREC_MIN`

is equal to 2.

The rounding mode specifies the way to round the result of a
floating-point operation, in case the exact result can not be represented
exactly in the destination mantissa;
the corresponding C data type is `mp_rnd_t`

.

A limb means the part of a multi-precision number that fits in a single
word. (We chose this word because a limb of the human body is analogous to a
digit, only larger, and containing several digits.) Normally a limb contains
32 or 64 bits. The C data type for a limb is `mp_limb_t`

.

There is only one class of functions in the MPFR library:

- Functions for floating-point arithmetic, with names beginning with
`mpfr_`

. The associated type is`mpfr_t`

.

As a general rule, all MPFR functions expect output arguments before input arguments. This notation is based on an analogy with the assignment operator.

MPFR allows you to use the same variable for both input and output in the same
expression. For example, the main function for floating-point multiplication,
`mpfr_mul`

, can be used like this: `mpfr_mul (x, x, x, rnd_mode)`

.
This
computes the square of `x` with rounding mode `rnd_mode`

and puts the result back in `x`.

Before you can assign to an MPFR variable, you need to initialize it by calling one of the special initialization functions. When you're done with a variable, you need to clear it out, using one of the functions for that purpose.

A variable should only be initialized once, or at least cleared out between each initialization. After a variable has been initialized, it may be assigned to any number of times.

For efficiency reasons, avoid to initialize and clear out a variable in loops. Instead, initialize it before entering the loop, and clear it out after the loop has exited.

You don't need to be concerned about allocating additional space for MPFR variables, since any variable has a mantissa of fixed size. Hence unless you change its precision, or clear and reinitialize it, a floating-point variable will have the same allocated space during all its life.

The following four rounding modes are supported:

`GMP_RNDN`

: round to nearest`GMP_RNDZ`

: round towards zero`GMP_RNDU`

: round towards plus infinity`GMP_RNDD`

: round towards minus infinity

The ``round to nearest`' mode works as in the IEEE 754-1985 standard: in
case the number to be rounded lies exactly in the middle of two representable
numbers, it is rounded to the one with the least significant bit set to zero.
For example, the number 5/2, which is represented by (10.1) in binary, is
rounded to (10.0)=2 with a precision of two bits, and not to (11.0)=3.
This rule avoids the drift phenomenon mentioned by Knuth in volume 2
of The Art of Computer Programming (Section 4.2.2).

Most MPFR functions take as first argument the destination variable, as
second and following arguments the input variables, as last argument a
rounding mode, and have a return value of type `int`

, called the
ternary value. The value stored in the destination variable is
correctly rounded, i.e. MPFR behaves as if it computed the result with
an infinite precision, then rounded it to the precision of this variable.
The input variables are regarded as exact (in particular, their precision
does not affect the result).

As a consequence, in case of a non-zero real rounded result, the error on the result is less or equal to 1/2 ulp (unit in the last place) of the target in the rounding to nearest mode, and less than 1 ulp of the target in the directed rounding modes (a ulp is the weight of the least significant represented bit of the target after rounding).

Unless documented otherwise, functions returning an `int`

return
a ternary value.
If the ternary value is zero, it means that the value stored in the
destination variable is the exact result of the corresponding mathematical
function. If the ternary value is positive (resp. negative), it means
the value stored in the destination variable is greater (resp. lower)
than the exact result. For example with the `GMP_RNDU`

rounding mode,
the ternary value is usually positive, except when the result is exact, in
which case it is zero. In the case of an infinite result, it is considered
as inexact when it was obtained by overflow, and exact otherwise. A NaN
result (Not-a-Number) always corresponds to an exact return value.
The opposite of a returned ternary value is guaranteed to be representable
in an `int`

.

Unless documented otherwise, functions returning a `1`

(or any other value specified in this manual)
for special cases (like `acos(0)`

) should return an overflow or
an underflow if `1`

is not representable in the current exponent range.

This section specifies the floating-point values (of type `mpfr_t`

)
returned by MPFR functions. For functions returning several values (like
`mpfr_sin_cos`

), the rules apply to each result separately.

Functions can have one or several input arguments. An input point is a mapping from these input arguments to the set of the MPFR numbers. When none of its components are NaN, an input point can also be seen as a tuple in the extended real numbers (the set of the real numbers with both infinities).

When the input point is in the domain of the mathematical function, the result is rounded as described in Section “Rounding Modes” (but see below for the specification of the sign of an exact zero). Otherwise the general rules from this section apply unless stated otherwise in the description of the MPFR function (MPFR Interface).

When the input point is not in the domain of the mathematical function
but is in its closure in the extended real numbers and the function can
be extended by continuity, the result is the obtained limit.
Examples: `mpfr_hypot`

on (+Inf,0) gives +Inf. But `mpfr_pow`

cannot be defined on (1,+Inf) using this rule, as one can find
sequences (`x`_`n`,`y`_`n`) such that
`x`_`n` goes to 1, `y`_`n` goes to +Inf
and `x`_`n` to the `y`_`n` goes to any
positive value when `n` goes to the infinity.

When the input point is in the closure of the domain of the mathematical
function and an input argument is +0 (resp. −0), one considers
the limit when the corresponding argument approaches 0 from above
(resp. below). If the limit is not defined (e.g., `mpfr_log`

on
−0), the behavior must be specified in the description of the
MPFR function.

When the result is equal to 0, its sign is determined by considering the
limit as if the input point were not in the domain: If one approaches 0
from above (resp. below), the result is +0 (resp. −0). In the
other cases, the sign must be specified in the description of the MPFR
function. Example: `mpfr_sin`

on +0 gives +0.

When the input point is not in the closure of the domain of the function,
the result is NaN. Example: `mpfr_sqrt`

on −17 gives NaN.

When an input argument is NaN, the result is NaN, possibly except when
a partial function is constant on the finite floating-point numbers;
such a case is always explicitly specified in MPFR Interface.
Example: `mpfr_hypot`

on (NaN,0) gives NaN, but `mpfr_hypot`

on (NaN,+Inf) gives +Inf (as specified in Special Functions),
since for any finite input `x`, `mpfr_hypot`

on (`x`,+Inf)
gives +Inf.

MPFR supports 5 exception types:

- Underflow:
An underflow occurs when the exact result of a function is a non-zero
real number and the result obtained after the rounding, assuming an
unbounded exponent range (for the rounding), has an exponent smaller
than the minimum exponent of the current range. In the round-to-nearest
mode, the halfway case is rounded toward zero.
Note: This is not the single definition of the underflow. MPFR chooses to consider the underflow after rounding. The underflow before rounding can also be defined. For instance, consider a function that has the exact result 7 multiplied by two to the power

`e`−4, where`e`is the smallest exponent (for a mantissa between 1/2 and 1) in the current range, with a 2-bit target precision and rounding towards plus infinity. The exact result has the exponent`e`−1. With the underflow before rounding, such a function call would yield an underflow, as`e`−1 is outside the current exponent range. However, MPFR first considers the rounded result assuming an unbounded exponent range. The exact result cannot be represented exactly in precision 2, and here, it is rounded to 0.5 times 2 to`e`, which is representable in the current exponent range. As a consequence, this will not yield an underflow in MPFR. - Overflow: An overflow occurs when the exact result of a function is a non-zero real number and the result obtained after the rounding, assuming an unbounded exponent range (for the rounding), has an exponent larger than the maximum exponent of the current range. In the round-to-nearest mode, the result is infinite.
- NaN: A NaN exception occurs when the result of a function is a NaN.
- Inexact: An inexact exception occurs when the result of a function cannot be represented exactly and must be rounded.
- Range error:
A range exception occurs when a function that does not return a MPFR
number (such as comparisons and conversions to an integer) has an
invalid result (e.g. an argument is NaN in
`mpfr_cmp`

or in a conversion to an integer).

MPFR has a global flag for each exception, which can be cleared, set or tested by functions described in Exception Related Functions.

Differences with the ISO C99 standard:

- In C, only quiet NaNs are specified, and a NaN propagation does not raise an invalid exception. Unless explicitly stated otherwise, MPFR sets the NaN flag whenever a NaN is generated, even when a NaN is propagated (e.g. in NaN + NaN), as if all NaNs were signaling.
- An invalid exception in C corresponds to either a NaN exception or a range error in MPFR.

The floating-point functions expect arguments of type `mpfr_t`

.

The MPFR floating-point functions have an interface that is similar to the
GNU MP
integer functions. The function prefix for floating-point operations is
`mpfr_`

.

There is one significant characteristic of floating-point numbers that has motivated a difference between this function class and other GNU MP function classes: the inherent inexactness of floating-point arithmetic. The user has to specify the precision for each variable. A computation that assigns a variable will take place with the precision of the assigned variable; the cost of that computation should not depend from the precision of variables used as input (on average).

The semantics of a calculation in MPFR is specified as follows: Compute the requested operation exactly (with “infinite accuracy”), and round the result to the precision of the destination variable, with the given rounding mode. The MPFR floating-point functions are intended to be a smooth extension of the IEEE 754-1985 arithmetic. The results obtained on one computer should not differ from the results obtained on a computer with a different word size.

MPFR does not keep track of the accuracy of a computation. This is left to the user or to a higher layer. As a consequence, if two variables are used to store only a few significant bits, and their product is stored in a variable with large precision, then MPFR will still compute the result with full precision.

The value of the standard C macro `errno`

may be set to non-zero by
any MPFR function or macro, whether or not there is an error.

An `mpfr_t`

object must be initialized before storing the first value in
it. The functions `mpfr_init`

and `mpfr_init2`

are used for that
purpose.

— Function: void **mpfr_init2** (`mpfr_t x, mp_prec_t prec`)

Initialize

x, set its precision to beexactlyprecbits and its value to NaN. (Warning: the corresponding`mpf`

functions initialize to zero instead.)Normally, a variable should be initialized once only or at least be cleared, using

`mpfr_clear`

, between initializations. To change the precision of a variable which has already been initialized, use`mpfr_set_prec`

. The precisionprecmust be an integer between`MPFR_PREC_MIN`

and`MPFR_PREC_MAX`

(otherwise the behavior is undefined).

— Function: void **mpfr_clear** (`mpfr_t x`)

Free the space occupied by

x. Make sure to call this function for all`mpfr_t`

variables when you are done with them.

— Function: void **mpfr_init** (`mpfr_t x`)

Initialize

xand set its value to NaN.Normally, a variable should be initialized once only or at least be cleared, using

`mpfr_clear`

, between initializations. The precision ofxis the default precision, which can be changed by a call to`mpfr_set_default_prec`

.

— Function: void **mpfr_set_default_prec** (`mp_prec_t prec`)

Set the default precision to be

exactlyprecbits. The precision of a variable means the number of bits used to store its mantissa. All subsequent calls to`mpfr_init`

will use this precision, but previously initialized variables are unaffected. This default precision is set to 53 bits initially. The precision can be any integer between`MPFR_PREC_MIN`

and`MPFR_PREC_MAX`

.

Here is an example on how to initialize floating-point variables:

{ mpfr_t x, y; mpfr_init (x); /* use default precision */ mpfr_init2 (y, 256); /* precisionexactly256 bits */ ... /* When the program is about to exit, do ... */ mpfr_clear (x); mpfr_clear (y); }

The following functions are useful for changing the precision during a calculation. A typical use would be for adjusting the precision gradually in iterative algorithms like Newton-Raphson, making the computation precision closely match the actual accurate part of the numbers.

— Function: void **mpfr_set_prec** (`mpfr_t x, mp_prec_t prec`)

Reset the precision of

xto beexactlyprecbits, and set its value to NaN. The previous value stored inxis lost. It is equivalent to a call to`mpfr_clear(x)`

followed by a call to`mpfr_init2(x, prec)`

, but more efficient as no allocation is done in case the current allocated space for the mantissa ofxis enough. The precisionpreccan be any integer between`MPFR_PREC_MIN`

and`MPFR_PREC_MAX`

.In case you want to keep the previous value stored in

x, use`mpfr_prec_round`

instead.

— Function: mp_prec_t **mpfr_get_prec** (`mpfr_t x`)

Return the precision actually used for assignments of

x, i.e. the number of bits used to store its mantissa.

Next: Combined Initialization and Assignment Functions, Previous: Initialization Functions, Up: MPFR Interface

These functions assign new values to already initialized floats
(see Initialization Functions). When using any functions using
`intmax_t`

, you must include `<stdint.h>`

or `<inttypes.h>`

before `mpfr.h`, to allow `mpfr.h` to define prototypes for
these functions.

— Function: int **mpfr_set** (`mpfr_t rop, mpfr_t op, mp_rnd_t rnd`)

— Function: int**mpfr_set_ui** (`mpfr_t rop, unsigned long int op, mp_rnd_t rnd`)

— Function: int**mpfr_set_si** (`mpfr_t rop, long int op, mp_rnd_t rnd`)

— Function: int**mpfr_set_uj** (`mpfr_t rop, uintmax_t op, mp_rnd_t rnd`)

— Function: int**mpfr_set_sj** (`mpfr_t rop, intmax_t op, mp_rnd_t rnd`)

— Function: int**mpfr_set_d** (`mpfr_t rop, double op, mp_rnd_t rnd`)

— Function: int**mpfr_set_ld** (`mpfr_t rop, long double op, mp_rnd_t rnd`)

— Function: int**mpfr_set_decimal64** (`mpfr_t rop, _Decimal64 op, mp_rnd_t rnd`)

— Function: int**mpfr_set_z** (`mpfr_t rop, mpz_t op, mp_rnd_t rnd`)

— Function: int**mpfr_set_q** (`mpfr_t rop, mpq_t op, mp_rnd_t rnd`)

— Function: int**mpfr_set_f** (`mpfr_t rop, mpf_t op, mp_rnd_t rnd`)

— Function: int

— Function: int

— Function: int

— Function: int

— Function: int

— Function: int

— Function: int

— Function: int

— Function: int

— Function: int

Set the value of

ropfromop, rounded towards the given directionrnd. Note that the input 0 is converted to +0 by`mpfr_set_ui`

,`mpfr_set_si`

,`mpfr_set_sj`

,`mpfr_set_uj`

,`mpfr_set_z`

,`mpfr_set_q`

and`mpfr_set_f`

, regardless of the rounding mode. If the system doesn't support the IEEE-754 standard,`mpfr_set_d`

,`mpfr_set_ld`

and`mpfr_set_decimal64`

might not preserve the signed zeros. The`mpfr_set_decimal64`

function is built only with the configure option `--enable-decimal-float', which also requires `--with-gmp-build', and when the compiler or system provides the `_Decimal64' data type (GCC version 4.2.0 is known to support this data type, but only when configured with `--enable-decimal-float' too).`mpfr_set_q`

might not be able to work if the numerator (or the denominator) can not be representable as a`mpfr_t`

.Note: If you want to store a floating-point constant to a

`mpfr_t`

, you should use`mpfr_set_str`

(or one of the MPFR constant functions, such as`mpfr_const_pi`

for Pi) instead of`mpfr_set_d`

,`mpfr_set_ld`

or`mpfr_set_decimal64`

. Otherwise the floating-point constant will be first converted into a reduced-precision (e.g., 53-bit) binary number before MPFR can work with it.

— Function: int **mpfr_set_ui_2exp** (`mpfr_t rop, unsigned long int op, mp_exp_t e, mp_rnd_t rnd`)

— Function: int**mpfr_set_si_2exp** (`mpfr_t rop, long int op, mp_exp_t e, mp_rnd_t rnd`)

— Function: int**mpfr_set_uj_2exp** (`mpfr_t rop, uintmax_t op, intmax_t e, mp_rnd_t rnd`)

— Function: int**mpfr_set_sj_2exp** (`mpfr_t rop, intmax_t op, intmax_t e, mp_rnd_t rnd`)

— Function: int

— Function: int

— Function: int

Set the value of

ropfromopmultiplied by two to the powere, rounded towards the given directionrnd. Note that the input 0 is converted to +0.

— Function: int **mpfr_set_str** (`mpfr_t rop, const char *s, int base, mp_rnd_t rnd`)

Set

ropto the value of the whole stringsin basebase, rounded in the directionrnd. See the documentation of`mpfr_strtofr`

for a detailed description of the valid string formats. This function returns 0 if the entire string up to the final null character is a valid number in basebase; otherwise it returns −1, andropmay have changed.

— Function: int **mpfr_strtofr** (`mpfr_t rop, const char *nptr, char **endptr, int base, mp_rnd_t rnd`)

Read a floating-point number from a string

nptrin basebase, rounded in the directionrnd. If successful, the result is stored inropand`*`

endptrpoints to the character just after those parsed. Ifstrdoesn't start with a valid number thenropis set to zero and the value ofnptris stored in the location referenced byendptr.Parsing follows the standard C

`strtod`

function. This means optional leading whitespace, an optional`+`

or`-`

, mantissa digits with an optional decimal point, and an optional exponent consisting of an`e`

or`E`

(ifbase<= 10) or`@`

, an optional sign, and digits. The decimal point can be either the one defined by the current locale or the period (the first one is accepted for consistency with the C standard and the practice, the second one is accepted to allow the programmer to provide MPFR numbers from strings in a way that does not depend on the current locale). A hexadecimal mantissa can be given with a leading`0x`

or`0X`

, in which case`p`

or`P`

may introduce an optional binary exponent, indicating the power of 2 by which the mantissa is to be scaled. A binary mantissa can be given with a leading`0b`

or`0B`

, in which case`e`

,`E`

,`p`

,`P`

or`@`

may introduce the binary exponent. The exponent is always written in base 10.In addition,

`infinity`

,`inf`

(ifbase<= 10) or`@inf@`

with an optional sign, or`nan`

,`nan(n-char-sequence)`

(ifbase<= 10),`@nan@`

or`@nan@(n-char-sequence)`

all case insensitive (as Latin letters), can be given. A`n-char-sequence`

is a non-empty string containing only digits, Latin letters and the underscore (0, 1, 2, ..., 9, a, b, ..., z, A, B, ..., Z, _).There must be at least one digit in the mantissa for the number to be valid. If an exponent has no digits it's ignored and parsing stops after the mantissa. If an

`0x`

,`0X`

,`0b`

or`0B`

is not followed by hexadecimal/binary digits, parsing stops after the first`0`

: the subject sequence is defined as the longest initial subsequence of the input string, starting with the first non-white-space character, that is of the expected form. The subject sequence contains no characters if the input string is not of the expected form.Note that in the hex format the exponent

`P`

represents a power of 2, whereas`@`

represents a power of the base (i.e. 16).If the argument

baseis different from 0, it must be in the range 2 to 36. Case is ignored; uppercase and lowercase letters have the same value.If

`base`

is 0, then it tries to identify the used base: if the mantissa begins with the`0x`

prefix, it assumes thatbaseis 16. If it begins with`0b`

, it assumes thatbaseis 2. Otherwise, it assumes it is 10.It returns a usual ternary value. If

endptris not a null pointer, a pointer to the character after the last character used in the conversion is stored in the location referenced byendptr.

— Function: void **mpfr_set_inf** (`mpfr_t x, int sign`)

— Function: void**mpfr_set_nan** (`mpfr_t x`)

— Function: void

Set the variable

xto infinity or NaN (Not-a-Number) respectively. In`mpfr_set_inf`

,xis set to plus infinity iffsignis nonnegative.

— Function: void **mpfr_swap** (`mpfr_t x, mpfr_t y`)

Swap the values

xandyefficiently. Warning: the precisions are exchanged too; in case the precisions are different,`mpfr_swap`

is thus not equivalent to three`mpfr_set`

calls using a third auxiliary variable.

— Macro: int **mpfr_init_set** (`mpfr_t rop, mpfr_t op, mp_rnd_t rnd`)

— Macro: int**mpfr_init_set_ui** (`mpfr_t rop, unsigned long int op, mp_rnd_t rnd`)

— Macro: int**mpfr_init_set_si** (`mpfr_t rop, signed long int op, mp_rnd_t rnd`)

— Macro: int**mpfr_init_set_d** (`mpfr_t rop, double op, mp_rnd_t rnd`)

— Macro: int**mpfr_init_set_ld** (`mpfr_t rop, long double op, mp_rnd_t rnd`)

— Macro: int**mpfr_init_set_z** (`mpfr_t rop, mpz_t op, mp_rnd_t rnd`)

— Macro: int**mpfr_init_set_q** (`mpfr_t rop, mpq_t op, mp_rnd_t rnd`)

— Macro: int**mpfr_init_set_f** (`mpfr_t rop, mpf_t op, mp_rnd_t rnd`)

— Macro: int

— Macro: int

— Macro: int

— Macro: int

— Macro: int

— Macro: int

— Macro: int

Initialize

ropand set its value fromop, rounded in the directionrnd. The precision ofropwill be taken from the active default precision, as set by`mpfr_set_default_prec`

.

— Function: int **mpfr_init_set_str** (`mpfr_t x, const char *s, int base, mp_rnd_t rnd`)

Initialize

xand set its value from the stringsin basebase, rounded in the directionrnd. See`mpfr_set_str`

.

Next: Basic Arithmetic Functions, Previous: Combined Initialization and Assignment Functions, Up: MPFR Interface

— Function: double **mpfr_get_d** (`mpfr_t op, mp_rnd_t rnd`)

— Function: long double**mpfr_get_ld** (`mpfr_t op, mp_rnd_t rnd`)

— Function: _Decimal64**mpfr_get_decimal64** (`mpfr_t op, mp_rnd_t rnd`)

— Function: long double

— Function: _Decimal64

Convert

opto a`double`

(respectively`_Decimal64`

or`long double`

), using the rounding modernd. Ifopis NaN, some fixed NaN (either quiet or signaling) or the result of 0.0/0.0 is returned. Ifopis ±Inf, an infinity of the same sign or the result of ±1.0/0.0 is returned. Ifopis zero, these functions return a zero, trying to preserve its sign, if possible. The`mpfr_get_decimal64`

function is built only under some conditions: see the documentation of`mpfr_set_decimal64`

.

— Function: double **mpfr_get_d_2exp** (`long *exp, mpfr_t op, mp_rnd_t rnd`)

— Function: long double**mpfr_get_ld_2exp** (`long *exp, mpfr_t op, mp_rnd_t rnd`)

— Function: long double

Return

dand setexpsuch that 0.5<=abs(d)<1 anddtimes 2 raised toexpequalsoprounded to double (resp. long double) precision, using the given rounding mode. Ifopis zero, then a zero of the same sign (or an unsigned zero, if the implementation does not have signed zeros) is returned, andexpis set to 0. Ifopis NaN or an infinity, then the corresponding double precision (resp. long-double precision) value is returned, andexpis undefined.

— Function: long **mpfr_get_si** (`mpfr_t op, mp_rnd_t rnd`)

— Function: unsigned long**mpfr_get_ui** (`mpfr_t op, mp_rnd_t rnd`)

— Function: intmax_t**mpfr_get_sj** (`mpfr_t op, mp_rnd_t rnd`)

— Function: uintmax_t**mpfr_get_uj** (`mpfr_t op, mp_rnd_t rnd`)

— Function: unsigned long

— Function: intmax_t

— Function: uintmax_t

Convert

opto a`long`

, an`unsigned long`

, an`intmax_t`

or an`uintmax_t`

(respectively) after rounding it with respect tornd. Ifopis NaN, the result is undefined. Ifopis too big for the return type, it returns the maximum or the minimum of the corresponding C type, depending on the direction of the overflow. The flag erange is set too. See also`mpfr_fits_slong_p`

,`mpfr_fits_ulong_p`

,`mpfr_fits_intmax_p`

and`mpfr_fits_uintmax_p`

.

— Function: mp_exp_t **mpfr_get_z_exp** (`mpz_t rop, mpfr_t op`)

Put the scaled mantissa of

op(regarded as an integer, with the precision ofop) intorop, and return the exponentexp(which may be outside the current exponent range) such thatopexactly equalsropmultiplied by two exponentexp. If the exponent is not representable in the`mp_exp_t`

type, the behavior is undefined.

— Function: void **mpfr_get_z** (`mpz_t rop, mpfr_t op, mp_rnd_t rnd`)

Convert

opto a`mpz_t`

, after rounding it with respect tornd. Ifopis NaN or Inf, the result is undefined.

— Function: int **mpfr_get_f** (`mpf_t rop, mpfr_t op, mp_rnd_t rnd`)

Convert

opto a`mpf_t`

, after rounding it with respect tornd. Return zero iff no error occurred, in particular a non-zero value is returned ifopis NaN or Inf, which do not exist in`mpf`

.

— Function: char * **mpfr_get_str** (`char *str, mp_exp_t *expptr, int b, size_t n, mpfr_t op, mp_rnd_t rnd`)

Convert

opto a string of digits in baseb, with rounding in the directionrnd, wherenis either zero (see below) or the number of significant digits; in the latter case,nmust be greater or equal to 2. The base may vary from 2 to 36.The generated string is a fraction, with an implicit radix point immediately to the left of the first digit. For example, the number −3.1416 would be returned as "−31416" in the string and 1 written at

expptr. Ifrndis to nearest, andopis exactly in the middle of two possible outputs, the one with an even last digit is chosen (for an odd base, this may not correspond to an even mantissa).If

nis zero, the number of digits of the mantissa is chosen large enough so that re-reading the printed value with the same precision, assuming both output and input use rounding to nearest, will recover the original value ofop. More precisely, in most cases, the chosen precision ofstris the minimal precision depending onnandbonly that satisfies the above property, i.e., m = 1 + ceil(n*log(2)/log(b)), but in some very rare cases, it might be m+1.If

stris a null pointer, space for the mantissa is allocated using the current allocation function, and a pointer to the string is returned. To free the returned string, you must use`mpfr_free_str`

.If

stris not a null pointer, it should point to a block of storage large enough for the mantissa, i.e., at least`max(`

n`+ 2, 7)`

. The extra two bytes are for a possible minus sign, and for the terminating null character.If the input number is an ordinary number, the exponent is written through the pointer

expptr(the current minimal exponent for 0).A pointer to the string is returned, unless there is an error, in which case a null pointer is returned.

— Function: void **mpfr_free_str** (`char *str`)

Free a string allocated by

`mpfr_get_str`

using the current unallocation function (preliminary interface). The block is assumed to be`strlen(`

str`)+1`

bytes. For more information about how it is done: see Custom Allocation (GNU MP).

— Function: int **mpfr_fits_ulong_p** (`mpfr_t op, mp_rnd_t rnd`)

— Function: int**mpfr_fits_slong_p** (`mpfr_t op, mp_rnd_t rnd`)

— Function: int**mpfr_fits_uint_p** (`mpfr_t op, mp_rnd_t rnd`)

— Function: int**mpfr_fits_sint_p** (`mpfr_t op, mp_rnd_t rnd`)

— Function: int**mpfr_fits_ushort_p** (`mpfr_t op, mp_rnd_t rnd`)

— Function: int**mpfr_fits_sshort_p** (`mpfr_t op, mp_rnd_t rnd`)

— Function: int**mpfr_fits_intmax_p** (`mpfr_t op, mp_rnd_t rnd`)

— Function: int**mpfr_fits_uintmax_p** (`mpfr_t op, mp_rnd_t rnd`)

— Function: int

— Function: int

— Function: int

— Function: int

— Function: int

— Function: int

— Function: int

Return non-zero if

opwould fit in the respective C data type, when rounded to an integer in the directionrnd.

— Function: int **mpfr_add** (`mpfr_t rop, mpfr_t op1, mpfr_t op2, mp_rnd_t rnd`)

— Function: int**mpfr_add_ui** (`mpfr_t rop, mpfr_t op1, unsigned long int op2, mp_rnd_t rnd`)

— Function: int**mpfr_add_si** (`mpfr_t rop, mpfr_t op1, long int op2, mp_rnd_t rnd`)

— Function: int**mpfr_add_z** (`mpfr_t rop, mpfr_t op1, mpz_t op2, mp_rnd_t rnd`)

— Function: int**mpfr_add_q** (`mpfr_t rop, mpfr_t op1, mpq_t op2, mp_rnd_t rnd`)

— Function: int

— Function: int

— Function: int

— Function: int

Set

roptoop1+op2rounded in the directionrnd. For types having no signed zero, it is considered unsigned (i.e. (+0) + 0 = (+0) and (−0) + 0 = (−0)).

— Function: int **mpfr_sub** (`mpfr_t rop, mpfr_t op1, mpfr_t op2, mp_rnd_t rnd`)

— Function: int**mpfr_ui_sub** (`mpfr_t rop, unsigned long int op1, mpfr_t op2, mp_rnd_t rnd`)

— Function: int**mpfr_sub_ui** (`mpfr_t rop, mpfr_t op1, unsigned long int op2, mp_rnd_t rnd`)

— Function: int**mpfr_si_sub** (`mpfr_t rop, long int op1, mpfr_t op2, mp_rnd_t rnd`)

— Function: int**mpfr_sub_si** (`mpfr_t rop, mpfr_t op1, long int op2, mp_rnd_t rnd`)

— Function: int**mpfr_sub_z** (`mpfr_t rop, mpfr_t op1, mpz_t op2, mp_rnd_t rnd`)

— Function: int**mpfr_sub_q** (`mpfr_t rop, mpfr_t op1, mpq_t op2, mp_rnd_t rnd`)

— Function: int

— Function: int

— Function: int

— Function: int

— Function: int

— Function: int

Set

roptoop1-op2rounded in the directionrnd. For types having no signed zero, it is considered unsigned (i.e. (+0) − 0 = (+0), (−0) − 0 = (−0), 0 − (+0) = (−0) and 0 − (−0) = (+0)).

— Function: int **mpfr_mul** (`mpfr_t rop, mpfr_t op1, mpfr_t op2, mp_rnd_t rnd`)

— Function: int**mpfr_mul_ui** (`mpfr_t rop, mpfr_t op1, unsigned long int op2, mp_rnd_t rnd`)

— Function: int**mpfr_mul_si** (`mpfr_t rop, mpfr_t op1, long int op2, mp_rnd_t rnd`)

— Function: int**mpfr_mul_z** (`mpfr_t rop, mpfr_t op1, mpz_t op2, mp_rnd_t rnd`)

— Function: int**mpfr_mul_q** (`mpfr_t rop, mpfr_t op1, mpq_t op2, mp_rnd_t rnd`)

— Function: int

— Function: int

— Function: int

— Function: int

Set

roptoop1timesop2rounded in the directionrnd. When a result is zero, its sign is the product of the signs of the operands (for types having no signed zero, it is considered positive).

— Function: int **mpfr_sqr** (`mpfr_t rop, mpfr_t op, mp_rnd_t rnd`)

Set

ropto the square ofoprounded in the directionrnd.

— Function: int **mpfr_div** (`mpfr_t rop, mpfr_t op1, mpfr_t op2, mp_rnd_t rnd`)

— Function: int**mpfr_ui_div** (`mpfr_t rop, unsigned long int op1, mpfr_t op2, mp_rnd_t rnd`)

— Function: int**mpfr_div_ui** (`mpfr_t rop, mpfr_t op1, unsigned long int op2, mp_rnd_t rnd`)

— Function: int**mpfr_si_div** (`mpfr_t rop, long int op1, mpfr_t op2, mp_rnd_t rnd`)

— Function: int**mpfr_div_si** (`mpfr_t rop, mpfr_t op1, long int op2, mp_rnd_t rnd`)

— Function: int**mpfr_div_z** (`mpfr_t rop, mpfr_t op1, mpz_t op2, mp_rnd_t rnd`)

— Function: int**mpfr_div_q** (`mpfr_t rop, mpfr_t op1, mpq_t op2, mp_rnd_t rnd`)

— Function: int

— Function: int

— Function: int

— Function: int

— Function: int

— Function: int

Set

roptoop1/op2rounded in the directionrnd. When a result is zero, its sign is the product of the signs of the operands (for types having no signed zero, it is considered positive).

— Function: int **mpfr_sqrt** (`mpfr_t rop, mpfr_t op, mp_rnd_t rnd`)

— Function: int**mpfr_sqrt_ui** (`mpfr_t rop, unsigned long int op, mp_rnd_t rnd`)

— Function: int

Set

ropto the square root ofoprounded in the directionrnd. Return −0 ifopis −0 (to be consistent with the IEEE 754-1985 standard). Setropto NaN ifopis negative.

— Function: int **mpfr_cbrt** (`mpfr_t rop, mpfr_t op, mp_rnd_t rnd`)

— Function: int**mpfr_root** (`mpfr_t rop, mpfr_t op, unsigned long int k, mp_rnd_t rnd`)

— Function: int

Set

ropto the cubic root (resp. thekth root) ofoprounded in the directionrnd. An odd (resp. even) root of a negative number (including −Inf) returns a negative number (resp. NaN). Thekth root of −0 is defined to be −0, whatever the parity ofk.

— Function: int **mpfr_pow** (`mpfr_t rop, mpfr_t op1, mpfr_t op2, mp_rnd_t rnd`)

— Function: int**mpfr_pow_ui** (`mpfr_t rop, mpfr_t op1, unsigned long int op2, mp_rnd_t rnd`)

— Function: int**mpfr_pow_si** (`mpfr_t rop, mpfr_t op1, long int op2, mp_rnd_t rnd`)

— Function: int**mpfr_pow_z** (`mpfr_t rop, mpfr_t op1, mpz_t op2, mp_rnd_t rnd`)

— Function: int**mpfr_ui_pow_ui** (`mpfr_t rop, unsigned long int op1, unsigned long int op2, mp_rnd_t rnd`)

— Function: int**mpfr_ui_pow** (`mpfr_t rop, unsigned long int op1, mpfr_t op2, mp_rnd_t rnd`)

— Function: int

— Function: int

— Function: int

— Function: int

— Function: int

Set

roptoop1raised toop2, rounded in the directionrnd. Special values are currently handled as described in the ISO C99 standard for the`pow`

function (note this may change in future versions):

`pow(±0,`

y`)`

returns plus or minus infinity forya negative odd integer.`pow(±0,`

y`)`

returns plus infinity forynegative and not an odd integer.`pow(±0,`

y`)`

returns plus or minus zero forya positive odd integer.`pow(±0,`

y`)`

returns plus zero forypositive and not an odd integer.`pow(-1, ±Inf)`

returns 1.`pow(+1,`

y`)`

returns 1 for anyy, even a NaN.`pow(`

x`,`

y`)`

returns NaN for finite negativexand finite non-integery.`pow(`

x`, -Inf)`

returns plus infinity for 0 < abs(x) < 1, and plus zero for abs(x) > 1.`pow(`

x`, +Inf)`

returns plus zero for 0 < abs(x) < 1, and plus infinity for abs(x) > 1.`pow(-Inf,`

y`)`

returns minus zero forya negative odd integer.`pow(-Inf,`

y`)`

returns plus zero forynegative and not an odd integer.`pow(-Inf,`

y`)`

returns minus infinity forya positive odd integer.`pow(-Inf,`

y`)`

returns plus infinity forypositive and not an odd integer.`pow(+Inf,`

y`)`

returns plus zero forynegative, and plus infinity forypositive.

— Function: int **mpfr_neg** (`mpfr_t rop, mpfr_t op, mp_rnd_t rnd`)

Set

ropto -oprounded in the directionrnd. Just changes the sign ifropandopare the same variable.

— Function: int **mpfr_abs** (`mpfr_t rop, mpfr_t op, mp_rnd_t rnd`)

Set

ropto the absolute value ofop, rounded in the directionrnd. Just changes the sign ifropandopare the same variable.

— Function: int **mpfr_dim** (`mpfr_t rop, mpfr_t op1, mpfr_t op2, mp_rnd_t rnd`)

Set

ropto the positive difference ofop1andop2, i.e.,op1-op2rounded in the directionrndifop1>op2, and +0 otherwise. Returns NaN whenop1orop2is NaN.

— Function: int **mpfr_mul_2ui** (`mpfr_t rop, mpfr_t op1, unsigned long int op2, mp_rnd_t rnd`)

— Function: int**mpfr_mul_2si** (`mpfr_t rop, mpfr_t op1, long int op2, mp_rnd_t rnd`)

— Function: int

Set

roptoop1times 2 raised toop2rounded in the directionrnd. Just increases the exponent byop2whenropandop1are identical.

— Function: int **mpfr_div_2ui** (`mpfr_t rop, mpfr_t op1, unsigned long int op2, mp_rnd_t rnd`)

— Function: int**mpfr_div_2si** (`mpfr_t rop, mpfr_t op1, long int op2, mp_rnd_t rnd`)

— Function: int

Set

roptoop1divided by 2 raised toop2rounded in the directionrnd. Just decreases the exponent byop2whenropandop1are identical.

— Function: int **mpfr_cmp** (`mpfr_t op1, mpfr_t op2`)

— Function: int**mpfr_cmp_ui** (`mpfr_t op1, unsigned long int op2`)

— Function: int**mpfr_cmp_si** (`mpfr_t op1, signed long int op2`)

— Function: int**mpfr_cmp_d** (`mpfr_t op1, double op2`)

— Function: int**mpfr_cmp_ld** (`mpfr_t op1, long double op2`)

— Function: int**mpfr_cmp_z** (`mpfr_t op1, mpz_t op2`)

— Function: int**mpfr_cmp_q** (`mpfr_t op1, mpq_t op2`)

— Function: int**mpfr_cmp_f** (`mpfr_t op1, mpf_t op2`)

— Function: int

— Function: int

— Function: int

— Function: int

— Function: int

— Function: int

— Function: int

Compare

op1andop2. Return a positive value ifop1>op2, zero ifop1=op2, and a negative value ifop1<op2. Bothop1andop2are considered to their full own precision, which may differ. If one of the operands is NaN, set the erange flag and return zero.Note: These functions may be useful to distinguish the three possible cases. If you need to distinguish two cases only, it is recommended to use the predicate functions (e.g.,

`mpfr_equal_p`

for the equality) described below; they behave like the IEEE-754 comparisons, in particular when one or both arguments are NaN. But only floating-point numbers can be compared (you may need to do a conversion first).

— Function: int **mpfr_cmp_ui_2exp** (`mpfr_t op1, unsigned long int op2, mp_exp_t e`)

— Function: int**mpfr_cmp_si_2exp** (`mpfr_t op1, long int op2, mp_exp_t e`)

— Function: int

Compare

op1andop2multiplied by two to the powere. Similar as above.

— Function: int **mpfr_cmpabs** (`mpfr_t op1, mpfr_t op2`)

Compare |

op1| and |op2|. Return a positive value if |op1| > |op2|, zero if |op1| = |op2|, and a negative value if |op1| < |op2|. If one of the operands is NaN, set the erange flag and return zero.

— Function: int **mpfr_nan_p** (`mpfr_t op`)

— Function: int**mpfr_inf_p** (`mpfr_t op`)

— Function: int**mpfr_number_p** (`mpfr_t op`)

— Function: int**mpfr_zero_p** (`mpfr_t op`)

— Function: int

— Function: int

— Function: int

Return non-zero if

opis respectively NaN, an infinity, an ordinary number (i.e. neither NaN nor an infinity) or zero. Return zero otherwise.

— Macro: int **mpfr_sgn** (`mpfr_t op`)

Return a positive value if

op> 0, zero ifop= 0, and a negative value ifop< 0. If the operand is NaN, set the erange flag and return zero.

— Function: int **mpfr_greater_p** (`mpfr_t op1, mpfr_t op2`)

Return non-zero if

op1>op2, zero otherwise.

— Function: int **mpfr_greaterequal_p** (`mpfr_t op1, mpfr_t op2`)

Return non-zero if

op1>=op2, zero otherwise.

— Function: int **mpfr_lessequal_p** (`mpfr_t op1, mpfr_t op2`)

Return non-zero if

op1<=op2, zero otherwise.

— Function: int **mpfr_lessgreater_p** (`mpfr_t op1, mpfr_t op2`)

Return non-zero if

op1<op2orop1>op2(i.e. neitherop1, norop2is NaN, andop1<>op2), zero otherwise (i.e.op1and/orop2are NaN, orop1=op2).

— Function: int **mpfr_equal_p** (`mpfr_t op1, mpfr_t op2`)

Return non-zero if

op1=op2, zero otherwise (i.e.op1and/orop2are NaN, orop1<>op2).

— Function: int **mpfr_unordered_p** (`mpfr_t op1, mpfr_t op2`)

Return non-zero if

op1orop2is a NaN (i.e. they cannot be compared), zero otherwise.

All those functions, except explicitly stated, return zero for an exact return value, a positive value for a return value larger than the exact result, and a negative value otherwise.

— Function: int **mpfr_log** (`mpfr_t rop, mpfr_t op, mp_rnd_t rnd`)

— Function: int**mpfr_log2** (`mpfr_t rop, mpfr_t op, mp_rnd_t rnd`)

— Function: int**mpfr_log10** (`mpfr_t rop, mpfr_t op, mp_rnd_t rnd`)

— Function: int

— Function: int

Set

ropto the natural logarithm ofop, log2(op) or log10(op), respectively, rounded in the directionrnd. Return −Inf ifopis −0 (i.e. the sign of the zero has no influence on the result).

— Function: int **mpfr_exp** (`mpfr_t rop, mpfr_t op, mp_rnd_t rnd`)

— Function: int**mpfr_exp2** (`mpfr_t rop, mpfr_t op, mp_rnd_t rnd`)

— Function: int**mpfr_exp10** (`mpfr_t rop, mpfr_t op, mp_rnd_t rnd`)

— Function: int

— Function: int

Set

ropto the exponential ofop, to 2 power ofopor to 10 power ofop, respectively, rounded in the directionrnd.

— Function: int **mpfr_cos** (`mpfr_t rop, mpfr_t op, mp_rnd_t rnd`)

— Function: int**mpfr_sin** (`mpfr_t rop, mpfr_t op, mp_rnd_t rnd`)

— Function: int**mpfr_tan** (`mpfr_t rop, mpfr_t op, mp_rnd_t rnd`)

— Function: int

— Function: int

Set

ropto the cosine ofop, sine ofop, tangent ofop, rounded in the directionrnd.

— Function: int **mpfr_sec** (`mpfr_t rop, mpfr_t op, mp_rnd_t rnd`)

— Function: int**mpfr_csc** (`mpfr_t rop, mpfr_t op, mp_rnd_t rnd`)

— Function: int**mpfr_cot** (`mpfr_t rop, mpfr_t op, mp_rnd_t rnd`)

— Function: int

— Function: int

Set

ropto the secant ofop, cosecant ofop, cotangent ofop, rounded in the directionrnd.

— Function: int **mpfr_sin_cos** (`mpfr_t sop, mpfr_t cop, mpfr_t op, mp_rnd_t rnd`)

Set simultaneously

sopto the sine ofopandcopto the cosine ofop, rounded in the directionrndwith the corresponding precisions ofsopandcop. Return 0 iff both results are exact.

— Function: int **mpfr_acos** (`mpfr_t rop, mpfr_t op, mp_rnd_t rnd`)

— Function: int**mpfr_asin** (`mpfr_t rop, mpfr_t op, mp_rnd_t rnd`)

— Function: int**mpfr_atan** (`mpfr_t rop, mpfr_t op, mp_rnd_t rnd`)

— Function: int

— Function: int

Set

ropto the arc-cosine, arc-sine or arc-tangent ofop, rounded in the directionrnd.

— Function: int **mpfr_atan2** (`mpfr_t rop, mpfr_t y, mpfr_t x, mp_rnd_t rnd`)

Set

ropto the arc-tangent2 ofyandx, rounded in the directionrnd: if`x > 0`

,`atan2(y, x) = atan (y/x)`

; if`x < 0`

,`atan2(y, x) = sign(y)*(Pi - atan (abs(y/x)))`

.

`atan2(y, 0)`

does not raise any floating-point exception. Special values are currently handled as described in the ISO C99 standard for the`atan2`

function (note this may change in future versions):

`atan2(+0, -0)`

returns +Pi.`atan2(-0, -0)`

returns -Pi.`atan2(+0, +0)`

returns +0.`atan2(-0, +0)`

returns −0.`atan2(+0, x)`

returns +Pi for x < 0.`atan2(-0, x)`

returns -Pi for x < 0.`atan2(+0, x)`

returns +0 for x > 0.`atan2(-0, x)`

returns −0 for x > 0.`atan2(y, 0)`

returns -Pi/2 for y < 0.`atan2(y, 0)`

returns +Pi/2 for y > 0.`atan2(+Inf, -Inf)`

returns +3*Pi/4.`atan2(-Inf, -Inf)`

returns -3*Pi/4.`atan2(+Inf, +Inf)`

returns +Pi/4.`atan2(-Inf, +Inf)`

returns -Pi/4.`atan2(+Inf, x)`

returns +Pi/2 for finite x.`atan2(-Inf, x)`

returns -Pi/2 for finite x.`atan2(y, -Inf)`

returns +Pi for finite y > 0.`atan2(y, -Inf)`

returns -Pi for finite y < 0.`atan2(y, +Inf)`

returns +0 for finite y > 0.`atan2(y, +Inf)`

returns −0 for finite y < 0.

— Function: int **mpfr_cosh** (`mpfr_t rop, mpfr_t op, mp_rnd_t rnd`)

— Function: int**mpfr_sinh** (`mpfr_t rop, mpfr_t op, mp_rnd_t rnd`)

— Function: int**mpfr_tanh** (`mpfr_t rop, mpfr_t op, mp_rnd_t rnd`)

— Function: int

— Function: int

Set

ropto the hyperbolic cosine, sine or tangent ofop, rounded in the directionrnd.

— Function: int **mpfr_sech** (`mpfr_t rop, mpfr_t op, mp_rnd_t rnd`)

— Function: int**mpfr_csch** (`mpfr_t rop, mpfr_t op, mp_rnd_t rnd`)

— Function: int**mpfr_coth** (`mpfr_t rop, mpfr_t op, mp_rnd_t rnd`)

— Function: int

— Function: int

Set

ropto the hyperbolic secant ofop, cosecant ofop, cotangent ofop, rounded in the directionrnd.

— Function: int **mpfr_acosh** (`mpfr_t rop, mpfr_t op, mp_rnd_t rnd`)

— Function: int**mpfr_asinh** (`mpfr_t rop, mpfr_t op, mp_rnd_t rnd`)

— Function: int**mpfr_atanh** (`mpfr_t rop, mpfr_t op, mp_rnd_t rnd`)

— Function: int

— Function: int

Set

ropto the inverse hyperbolic cosine, sine or tangent ofop, rounded in the directionrnd.

— Function: int **mpfr_fac_ui** (`mpfr_t rop, unsigned long int op, mp_rnd_t rnd`)

Set

ropto the factorial of the`unsigned long int`

op, rounded in the directionrnd.

— Function: int **mpfr_log1p** (`mpfr_t rop, mpfr_t op, mp_rnd_t rnd`)

Set

ropto the logarithm of one plusop, rounded in the directionrnd.

— Function: int **mpfr_expm1** (`mpfr_t rop, mpfr_t op, mp_rnd_t rnd`)

Set

ropto the exponential ofopminus one, rounded in the directionrnd.

— Function: int **mpfr_eint** (`mpfr_t y, mpfr_t x, mp_rnd_t rnd`)

Set

yto the exponential integral ofx, rounded in the directionrnd. For positivex, the exponential integral is the sum of Euler's constant, of the logarithm ofx, and of the sum for k from 1 to infinity ofxto the power k, divided by k and factorial(k). For negativex, the returned value is NaN.

— Function: int **mpfr_gamma** (`mpfr_t rop, mpfr_t op, mp_rnd_t rnd`)

Set

ropto the value of the Gamma function onop, rounded in the directionrnd. Whenopis a negative integer, NaN is returned.

— Function: int **mpfr_lngamma** (`mpfr_t rop, mpfr_t op, mp_rnd_t rnd`)

Set

ropto the value of the logarithm of the Gamma function onop, rounded in the directionrnd. When −2k−1 <=x<= −2k,kbeing a non-negative integer, NaN is returned. See also`mpfr_lgamma`

.

— Function: int **mpfr_lgamma** (`mpfr_t rop, int *signp, mpfr_t op, mp_rnd_t rnd`)

Set

ropto the value of the logarithm of the absolute value of the Gamma function onop, rounded in the directionrnd. The sign (1 or −1) of Gamma(op) is returned in the object pointed to bysignp. Whenopis an infinity or a non-positive integer, +Inf is returned. Whenopis NaN, −Inf or a negative integer, *signpis undefined, and whenopis ±0, *signpis the sign of the zero.

— Function: int **mpfr_zeta** (`mpfr_t rop, mpfr_t op, mp_rnd_t rnd`)

— Function: int**mpfr_zeta_ui** (`mpfr_t rop, unsigned long op, mp_rnd_t rnd`)

— Function: int

Set

ropto the value of the Riemann Zeta function onop, rounded in the directionrnd.

— Function: int **mpfr_erf** (`mpfr_t rop, mpfr_t op, mp_rnd_t rnd`)

Set

ropto the value of the error function onop, rounded in the directionrnd.

— Function: int **mpfr_erfc** (`mpfr_t rop, mpfr_t op, mp_rnd_t rnd`)

Set

ropto the value of the complementary error function onop, rounded in the directionrnd.

— Function: int **mpfr_j0** (`mpfr_t rop, mpfr_t op, mp_rnd_t rnd`)

— Function: int**mpfr_j1** (`mpfr_t rop, mpfr_t op, mp_rnd_t rnd`)

— Function: int**mpfr_jn** (`mpfr_t rop, long n, mpfr_t op, mp_rnd_t rnd`)

— Function: int

— Function: int

Set

ropto the value of the first order Bessel function of order 0, 1 andnonop, rounded in the directionrnd. Whenopis NaN,ropis always set to NaN. Whenopis plus or minus Infinity,ropis set to +0. Whenopis zero, andnis not zero,ropis +0 or −0 depending on the parity and sign ofn, and the sign ofop.

— Function: int **mpfr_y0** (`mpfr_t rop, mpfr_t op, mp_rnd_t rnd`)

— Function: int**mpfr_y1** (`mpfr_t rop, mpfr_t op, mp_rnd_t rnd`)

— Function: int**mpfr_yn** (`mpfr_t rop, long n, mpfr_t op, mp_rnd_t rnd`)

— Function: int

— Function: int

Set

ropto the value of the second order Bessel function of order 0, 1 andnonop, rounded in the directionrnd. Whenopis NaN or negative,ropis always set to NaN. Whenopis +Inf,ropis +0. Whenopis zero,ropis +Inf or −Inf depending on the parity and sign ofn.

— Function: int **mpfr_fma** (`mpfr_t rop, mpfr_t op1, mpfr_t op2, mpfr_t op3, mp_rnd_t rnd`)

Set

roptoop1timesop2+op3, rounded in the directionrnd.

— Function: int **mpfr_fms** (`mpfr_t rop, mpfr_t op1, mpfr_t op2, mpfr_t op3, mp_rnd_t rnd`)

Set

roptoop1timesop2-op3, rounded in the directionrnd.

— Function: int **mpfr_agm** (`mpfr_t rop, mpfr_t op1, mpfr_t op2, mp_rnd_t rnd`)

Set

ropto the arithmetic-geometric mean ofop1andop2, rounded in the directionrnd. The arithmetic-geometric mean is the common limit of the sequences u[n] and v[n], where u[0]=op1, v[0]=op2, u[n+1] is the arithmetic mean of u[n] and v[n], and v[n+1] is the geometric mean of u[n] and v[n]. If any operand is negative, the return value is NaN.

— Function: int **mpfr_hypot** (`mpfr_t rop, mpfr_t x, mpfr_t y, mp_rnd_t rnd`)

Set

ropto the Euclidean norm ofxandy, i.e. the square root of the sum of the squares ofxandy, rounded in the directionrnd. Special values are currently handled as described in Section F.9.4.3 of the ISO C99 standard, for the`hypot`

function (note this may change in future versions): Ifxoryis an infinity, then plus infinity is returned inrop, even if the other number is NaN.

— Function: int **mpfr_const_log2** (`mpfr_t rop, mp_rnd_t rnd`)

— Function: int**mpfr_const_pi** (`mpfr_t rop, mp_rnd_t rnd`)

— Function: int**mpfr_const_euler** (`mpfr_t rop, mp_rnd_t rnd`)

— Function: int**mpfr_const_catalan** (`mpfr_t rop, mp_rnd_t rnd`)

— Function: int

— Function: int

— Function: int

Set

ropto the logarithm of 2, the value of Pi, of Euler's constant 0.577..., of Catalan's constant 0.915..., respectively, rounded in the directionrnd. These functions cache the computed values to avoid other calculations if a lower or equal precision is requested. To free these caches, use`mpfr_free_cache`

.

— Function: void **mpfr_free_cache** (`void`)

Free various caches used by MPFR internally, in particular the caches used by the functions computing constants (currently

`mpfr_const_log2`

,`mpfr_const_pi`

,`mpfr_const_euler`

and`mpfr_const_catalan`

). You should call this function when terminating a thread.

— Function: int **mpfr_sum** (`mpfr_t rop, mpfr_ptr const tab`[]`, unsigned long n, mp_rnd_t rnd`)

Set

retto the sum of all elements oftabwhose size isn, rounded in the directionrnd. Warning,tabis a table of pointers to mpfr_t, not a table of mpfr_t (preliminary interface). The returned`int`

value is zero when the computed value is the exact value, and non-zero when this cannot be guaranteed, without giving the direction of the error as the other functions do.

This section describes functions that perform input from an input/output
stream, and functions that output to an input/output stream.
Passing a null pointer for a `stream` argument to any of
these functions will make them read from `stdin`

and write to
`stdout`

, respectively.

When using any of these functions, you must include the `<stdio.h>`

standard header before `mpfr.h`, to allow `mpfr.h` to define
prototypes for these functions.

— Function: size_t **mpfr_out_str** (`FILE *stream, int base, size_t n, mpfr_t op, mp_rnd_t rnd`)

Output

opon streamstream, as a string of digits in basebase, rounded in the directionrnd. The base may vary from 2 to 36. Printnsignificant digits exactly, or ifnis 0, enough digits so thatopcan be read back exactly (see`mpfr_get_str`

).In addition to the significant digits, a decimal point (defined by the current locale) at the right of the first digit and a trailing exponent in base 10, in the form `

eNNN', are printed. Ifbaseis greater than 10, `@' will be used instead of `e' as exponent delimiter.Return the number of bytes written, or if an error occurred, return 0.

— Function: size_t **mpfr_inp_str** (`mpfr_t rop, FILE *stream, int base, mp_rnd_t rnd`)

Input a string in base

basefrom streamstream, rounded in the directionrnd, and put the read float inrop.This function reads a word (defined as a sequence of characters between whitespace) and parses it using

`mpfr_set_str`

(it may change). See the documentation of`mpfr_strtofr`

for a detailed description of the valid string formats.Return the number of bytes read, or if an error occurred, return 0.

— Function: int **mpfr_rint** (`mpfr_t rop, mpfr_t op, mp_rnd_t rnd`)

— Function: int**mpfr_ceil** (`mpfr_t rop, mpfr_t op`)

— Function: int**mpfr_floor** (`mpfr_t rop, mpfr_t op`)

— Function: int**mpfr_round** (`mpfr_t rop, mpfr_t op`)

— Function: int**mpfr_trunc** (`mpfr_t rop, mpfr_t op`)

— Function: int

— Function: int

— Function: int

— Function: int

Set

roptooprounded to an integer.`mpfr_rint`

rounds to the nearest representable integer in the given rounding mode,`mpfr_ceil`

rounds to the next higher or equal representable integer,`mpfr_floor`

to the next lower or equal representable integer,`mpfr_round`

to the nearest representable integer, rounding halfway cases away from zero, and`mpfr_trunc`

to the next representable integer towards zero.The returned value is zero when the result is exact, positive when it is greater than the original value of

op, and negative when it is smaller. More precisely, the returned value is 0 whenopis an integer representable inrop, 1 or −1 whenopis an integer that is not representable inrop, 2 or −2 whenopis not an integer.Note that

`mpfr_round`

is different from`mpfr_rint`

called with the rounding to the nearest mode (where halfway cases are rounded to an even integer or mantissa). Note also that no double rounding is performed; for instance, 4.5 (100.1 in binary) is rounded by`mpfr_round`

to 4 (100 in binary) in 2-bit precision, though`round(4.5)`

is equal to 5 and 5 (101 in binary) is rounded to 6 (110 in binary) in 2-bit precision.

— Function: int **mpfr_rint_ceil** (`mpfr_t rop, mpfr_t op, mp_rnd_t rnd`)

— Function: int**mpfr_rint_floor** (`mpfr_t rop, mpfr_t op, mp_rnd_t rnd`)

— Function: int**mpfr_rint_round** (`mpfr_t rop, mpfr_t op, mp_rnd_t rnd`)

— Function: int**mpfr_rint_trunc** (`mpfr_t rop, mpfr_t op, mp_rnd_t rnd`)

— Function: int

— Function: int

— Function: int

Set

roptooprounded to an integer.`mpfr_rint_ceil`

rounds to the next higher or equal integer,`mpfr_rint_floor`

to the next lower or equal integer,`mpfr_rint_round`

to the nearest integer, rounding halfway cases away from zero, and`mpfr_rint_trunc`

to the next integer towards zero. If the result is not representable, it is rounded in the directionrnd. The returned value is the ternary value associated with the considered round-to-integer function (regarded in the same way as any other mathematical function).

— Function: int **mpfr_frac** (`mpfr_t rop, mpfr_t op, mp_rnd_t rnd`)

Set

ropto the fractional part ofop, having the same sign asop, rounded in the directionrnd(unlike in`mpfr_rint`

,rndaffects only how the exact fractional part is rounded, not how the fractional part is generated).

— Function: int **mpfr_remainder** (`mpfr_t r, mpfr_t x, mpfr_t y, mp_rnd_t rnd`)

— Function: int**mpfr_remquo** (`mpfr_t r, long* q, mpfr_t x, mpfr_t y, mp_rnd_t rnd`)

— Function: int

Set

rto the remainder of the division ofxbyy, with quotient rounded to the nearest integer (ties rounded to even), andrrounded according to the directionrnd. Ifris zero, it has the sign ofx. The return value is the inexact flag corresponding tor. Additionally,`mpfr_remquo`

stores the low significant bits from the quotient in*q(more precisely the number of bits in a`long`

minus one), with the sign ofxdivided byy(except if those low bits are all zero, in which case zero is returned). Note thatxmay be so large in magnitude relative toythat an exact representation of the quotient is not practical. These functions are useful for additive argument reduction.

— Function: void **mpfr_nexttoward** (`mpfr_t x, mpfr_t y`)

If

xoryis NaN, setxto NaN. Otherwise, ifxis different fromy, replacexby the next floating-point number (with the precision ofxand the current exponent range) in the direction ofy, if there is one (the infinite values are seen as the smallest and largest floating-point numbers). If the result is zero, it keeps the same sign. No underflow or overflow is generated.

— Function: int **mpfr_min** (`mpfr_t rop, mpfr_t op1, mpfr_t op2, mp_rnd_t rnd`)

Set

ropto the minimum ofop1andop2. Ifop1andop2are both NaN, thenropis set to NaN. Ifop1orop2is NaN, thenropis set to the numeric value. Ifop1andop2are zeros of different signs, thenropis set to −0.

— Function: int **mpfr_max** (`mpfr_t rop, mpfr_t op1, mpfr_t op2, mp_rnd_t rnd`)

Set

ropto the maximum ofop1andop2. Ifop1andop2are both NaN, thenropis set to NaN. Ifop1orop2is NaN, thenropis set to the numeric value. Ifop1andop2are zeros of different signs, thenropis set to +0.

— Function: int **mpfr_urandomb** (`mpfr_t rop, gmp_randstate_t state`)

Generate a uniformly distributed random float in the interval 0 <=

rop< 1. Return 0, unless the exponent is not in the current exponent range, in which caseropis set to NaN and a non-zero value is returned. The second argument is a`gmp_randstate_t`

structure which should be created using the GMP`gmp_randinit`

function, see the GMP manual.

— Function: void **mpfr_random** (`mpfr_t rop`)

Generate a uniformly distributed random float in the interval 0 <=

rop< 1. This function is deprecated;`mpfr_urandomb`

should be used instead.

— Function: void **mpfr_random2** (`mpfr_t rop, mp_size_t size, mp_exp_t exp`)

Generate a random float of at most

sizelimbs, with long strings of zeros and ones in the binary representation. The exponent of the number is in the interval −exptoexp. This function is useful for testing functions and algorithms, since this kind of random numbers have proven to be more likely to trigger corner-case bugs. Negative random numbers are generated whensizeis negative. Put +0 inropwhen size if zero. The internal state of the default pseudorandom number generator is modified by a call to this function (the same one as GMP if MPFR was built using `--with-gmp-build').

— Function: mp_exp_t **mpfr_get_exp** (`mpfr_t x`)

Get the exponent of

x, assuming thatxis a non-zero ordinary number. The behavior for NaN, Infinity or Zero is undefined.

— Function: int **mpfr_set_exp** (`mpfr_t x, mp_exp_t e`)

Set the exponent of

xifeis in the current exponent range, and return 0 (even ifxis not a non-zero ordinary number); otherwise, return a non-zero value.

— Function: int **mpfr_signbit** (`mpfr_t op`)

Return a non-zero value iff

ophas its sign bit set (i.e. if it is negative, −0, or a NaN whose representation has its sign bit set).

— Function: int **mpfr_setsign** (`mpfr_t rop, mpfr_t op, int s, mp_rnd_t rnd`)

Set the value of

ropfromop, rounded towards the given directionrnd, then set (resp. clear) its sign bit ifsis non-zero (resp. zero), even whenopis a NaN.

— Function: int **mpfr_copysign** (`mpfr_t rop, mpfr_t op1, mpfr_t op2, mp_rnd_t rnd`)

Set the value of

ropfromop1, rounded towards the given directionrnd, then set its sign bit to that ofop2(even whenop1orop2is a NaN). This function is equivalent to`mpfr_setsign (`

rop`,`

op1`, mpfr_signbit (`

op2`),`

rnd`)`

.

— Function: const char * **mpfr_get_version** (`void`)

Return the MPFR version, as a null-terminated string.

— Macro: **MPFR_VERSION**

— Macro:**MPFR_VERSION_MAJOR**

— Macro:**MPFR_VERSION_MINOR**

— Macro:**MPFR_VERSION_PATCHLEVEL**

— Macro:**MPFR_VERSION_STRING**

— Macro:

— Macro:

— Macro:

— Macro:

`MPFR_VERSION`

is the version of MPFR as a preprocessing constant.`MPFR_VERSION_MAJOR`

,`MPFR_VERSION_MINOR`

and`MPFR_VERSION_PATCHLEVEL`

are respectively the major, minor and patch level of MPFR version, as preprocessing constants.`MPFR_VERSION_STRING`

is the version (with an optional suffix, used in development and pre-release versions) as a string constant, which can be compared to the result of`mpfr_get_version`

to check at run time the header file and library used match:if (strcmp (mpfr_get_version (), MPFR_VERSION_STRING)) fprintf (stderr, "Warning: header and library do not match\n");Note: Obtaining different strings is not necessarily an error, as in general, a program compiled with some old MPFR version can be dynamically linked with a newer MPFR library version (if allowed by the library versioning system).

— Macro: long **MPFR_VERSION_NUM** (`major, minor, patchlevel`)

Create an integer in the same format as used by

`MPFR_VERSION`

from the givenmajor,minorandpatchlevel. Here is an example of how to check the MPFR version at compile time:#if (!defined(MPFR_VERSION) || (MPFR_VERSION<MPFR_VERSION_NUM(2,1,0))) # error "Wrong MPFR version." #endif

— Function: const char * **mpfr_get_patches** (`void`)

Return a null-terminated string containing the ids of the patches applied to the MPFR library (contents of the

PATCHESfile), separated by spaces. Note: If the program has been compiled with an older MPFR version and is dynamically linked with a new MPFR library version, the ids of the patches applied to the old (compile-time) MPFR version are not available (however this information should not have much interest in general).

— Function: void **mpfr_set_default_rounding_mode** (`mp_rnd_t rnd`)

Set the default rounding mode to

rnd. The default rounding mode is to nearest initially.

— Function: int **mpfr_prec_round** (`mpfr_t x, mp_prec_t prec, mp_rnd_t rnd`)

Round

xaccording torndwith precisionprec, which must be an integer between`MPFR_PREC_MIN`

and`MPFR_PREC_MAX`

(otherwise the behavior is undefined). Ifprecis greater or equal to the precision ofx, then new space is allocated for the mantissa, and it is filled with zeros. Otherwise, the mantissa is rounded to precisionprecwith the given direction. In both cases, the precision ofxis changed toprec.

— Function: int **mpfr_round_prec** (`mpfr_t x, mp_rnd_t rnd, mp_prec_t prec`)

[This function is obsolete. Please use

`mpfr_prec_round`

instead.]

— Function: const char * **mpfr_print_rnd_mode** (`mp_rnd_t rnd`)

Return the input string (GMP_RNDD, GMP_RNDU, GMP_RNDN, GMP_RNDZ) corresponding to the rounding mode

rndor a null pointer ifrndis an invalid rounding mode.

— Function: mp_exp_t **mpfr_get_emin** (`void`)

— Function: mp_exp_t**mpfr_get_emax** (`void`)

— Function: mp_exp_t

Return the (current) smallest and largest exponents allowed for a floating-point variable. The smallest positive value of a floating-point variable is one half times 2 raised to the smallest exponent and the largest value has the form (1 - epsilon) times 2 raised to the largest exponent.

— Function: int **mpfr_set_emin** (`mp_exp_t exp`)

— Function: int**mpfr_set_emax** (`mp_exp_t exp`)

— Function: int

Set the smallest and largest exponents allowed for a floating-point variable. Return a non-zero value when

expis not in the range accepted by the implementation (in that case the smallest or largest exponent is not changed), and zero otherwise. If the user changes the exponent range, it is her/his responsibility to check that all current floating-point variables are in the new allowed range (for example using`mpfr_check_range`

), otherwise the subsequent behavior will be undefined, in the sense of the ISO C standard.

— Function: mp_exp_t **mpfr_get_emin_min** (`void`)

— Function: mp_exp_t**mpfr_get_emin_max** (`void`)

— Function: mp_exp_t**mpfr_get_emax_min** (`void`)

— Function: mp_exp_t**mpfr_get_emax_max** (`void`)

— Function: mp_exp_t

— Function: mp_exp_t

— Function: mp_exp_t

Return the minimum and maximum of the smallest and largest exponents allowed for

`mpfr_set_emin`

and`mpfr_set_emax`

. These values are implementation dependent; it is possible to create a non portable program by writing`mpfr_set_emax(mpfr_get_emax_max())`

and`mpfr_set_emin(mpfr_get_emin_min())`

since the values of the smallest and largest exponents become implementation dependent.

— Function: int **mpfr_check_range** (`mpfr_t x, int t, mp_rnd_t rnd`)

This function forces

xto be in the current range of acceptable values,tbeing the current ternary value: negative ifxis smaller than the exact value, positive ifxis larger than the exact value and zero ifxis exact (before the call). It generates an underflow or an overflow if the exponent ofxis outside the current allowed range; the value oftmay be used to avoid a double rounding. This function returns zero if the rounded result is equal to the exact one, a positive value if the rounded result is larger than the exact one, a negative value if the rounded result is smaller than the exact one. Note that unlike most functions, the result is compared to the exact one, not the input valuex, i.e. the ternary value is propagated.

— Function: int **mpfr_subnormalize** (`mpfr_t x, int t, mp_rnd_t rnd`)

This function rounds

xemulating subnormal number arithmetic: ifxis outside the subnormal exponent range, it just propagates the ternary valuet; otherwise, it roundsxto precision`EXP(x)-emin+1`

according to rounding moderndand previous ternary valuet, avoiding double rounding problems.`PREC(x)`

is not modified by this function.rndandtmust be the used rounding mode for computingxand the returned ternary value when computingx. The subnormal exponent range is from`emin`

to`emin+PREC(x)-1`

. This functions assumes that`emax-emin >= PREC(x)`

. Note that unlike most functions, the result is compared to the exact one, not the input valuex, i.e. the ternary value is propagated. This is a preliminary interface.

This is an example of how to emulate double IEEE-754 arithmetic using MPFR:

{ mpfr_t xa, xb; int i; volatile double a, b; mpfr_set_default_prec (53); mpfr_set_emin (-1073); mpfr_set_emax (1024); mpfr_init (xa); mpfr_init (xb); b = 34.3; mpfr_set_d (xb, b, GMP_RNDN); a = 0x1.1235P-1021; mpfr_set_d (xa, a, GMP_RNDN); a /= b; i = mpfr_div (xa, xa, xb, GMP_RNDN); i = mpfr_subnormalize (xa, i, GMP_RNDN); mpfr_clear (xa); mpfr_clear (xb); }

Warning: this emulates a double IEEE-754 arithmetic with correct rounding in the subnormal range, which may not be the case for your hardware.

— Function: void **mpfr_clear_underflow** (`void`)

— Function: void**mpfr_clear_overflow** (`void`)

— Function: void**mpfr_clear_nanflag** (`void`)

— Function: void**mpfr_clear_inexflag** (`void`)

— Function: void**mpfr_clear_erangeflag** (`void`)

— Function: void

— Function: void

— Function: void

— Function: void

Clear the underflow, overflow, invalid, inexact and erange flags.

— Function: void **mpfr_set_underflow** (`void`)

— Function: void**mpfr_set_overflow** (`void`)

— Function: void**mpfr_set_nanflag** (`void`)

— Function: void**mpfr_set_inexflag** (`void`)

— Function: void**mpfr_set_erangeflag** (`void`)

— Function: void

— Function: void

— Function: void

— Function: void

Set the underflow, overflow, invalid, inexact and erange flags.

— Function: void **mpfr_clear_flags** (`void`)

Clear all global flags (underflow, overflow, inexact, invalid, erange).

— Function: int **mpfr_underflow_p** (`void`)

— Function: int**mpfr_overflow_p** (`void`)

— Function: int**mpfr_nanflag_p** (`void`)

— Function: int**mpfr_inexflag_p** (`void`)

— Function: int**mpfr_erangeflag_p** (`void`)

— Function: int

— Function: int

— Function: int

— Function: int

Return the corresponding (underflow, overflow, invalid, inexact, erange) flag, which is non-zero iff the flag is set.

All the given interfaces are preliminary. They might change incompatibly in future revisions.

— Macro: **MPFR_DECL_INIT** (`name, prec`)

This macro declares

nameas an automatic variable of type`mpfr_t`

, initializes it and sets its precision to beexactlyprecbits and its value to NaN.namemust be a valid identifier. You must use this macro in the declaration section. This macro is much faster than using`mpfr_init2`

but has some drawbacks:

- You
must notcall`mpfr_clear`

with variables created with this macro (The storage is allocated at the point of declaration and deallocated when the brace-level is exited.).- You
can notchange their precision.- You
should notcreate variables with huge precision with this macro.- Your compiler must support `
Non-Constant Initializers' (standard in C++ and ISO C99) and `Token Pasting' (standard in ISO C89). Ifprecis not a compiler constant, your compiler must support `Variable-length automatic arrays' (standard in ISO C99). `GCC 2.95.3' supports all these features. If you compile your program with gcc in c89 mode and with `-pedantic', you may want to define the`MPFR_USE_EXTENSION`

macro to avoid warnings due to the`MPFR_DECL_INIT`

implementation.

— Function: void **mpfr_inits** (`mpfr_t x, ...`)

Initialize all the

`mpfr_t`

variables of the given`va_list`

, set their precision to be the default precision and their value to NaN. See`mpfr_init`

for more details. The`va_list`

is assumed to be composed only of type`mpfr_t`

. It begins fromx. It ends when it encounters a null pointer.

— Function: void **mpfr_inits2** (`mp_prec_t prec, mpfr_t x, ...`)

Initialize all the

`mpfr_t`

variables of the given`va_list`

, set their precision to beexactlyprecbits and their value to NaN. See`mpfr_init2`

for more details. The`va_list`

is assumed to be composed only of type`mpfr_t`

. It begins fromx. It ends when it encounters a null pointer.

— Function: void **mpfr_clears** (`mpfr_t x, ...`)

Free the space occupied by all the

`mpfr_t`

variables of the given`va_list`

. See`mpfr_clear`

for more details. The`va_list`

is assumed to be composed only of type`mpfr_t`

. It begins fromx. It ends when it encounters a null pointer.

Here is an example of how to use multiple initialization functions:

{ mpfr_t x, y, z, t; mpfr_inits2 (256, x, y, z, t, (void *) 0); ... mpfr_clears (x, y, z, t, (void *) 0); }

A header file `mpf2mpfr.h` is included in the distribution of MPFR for
compatibility with the GNU MP class MPF.
After inserting the following two lines after the `#include <gmp.h>`

line,

#include <mpfr.h> #include <mpf2mpfr.h>any program written for MPF can be compiled directly with MPFR without any changes. All operations are then performed with the default MPFR rounding mode, which can be reset with

`mpfr_set_default_rounding_mode`

.
Warning: the `mpf_init`

and `mpf_init2`

functions initialize
to zero, whereas the corresponding `mpfr`

functions initialize to NaN:
this is useful to detect uninitialized values, but is slightly incompatible
with `mpf`

.

— Function: void **mpfr_set_prec_raw** (`mpfr_t x, mp_prec_t prec`)

Reset the precision of

xto beexactlyprecbits. The only difference with`mpfr_set_prec`

is thatprecis assumed to be small enough so that the mantissa fits into the current allocated memory space forx. Otherwise the behavior is undefined.

— Function: int **mpfr_eq** (`mpfr_t op1, mpfr_t op2, unsigned long int op3`)

Return non-zero if

op1andop2are both non-zero ordinary numbers with the same exponent and the same firstop3bits, both zero, or both infinities of the same sign. Return zero otherwise. This function is defined for compatibility with`mpf`

. Do not use it if you want to know whether two numbers are close to each other; for instance, 1.011111 and 1.100000 are regarded as different for any value ofop3larger than 1.

— Function: void **mpfr_reldiff** (`mpfr_t rop, mpfr_t op1, mpfr_t op2, mp_rnd_t rnd`)

Compute the relative difference between

op1andop2and store the result inrop. This function does not guarantee the correct rounding on the relative difference; it just computes |op1-op2|/op1, using the rounding moderndfor all operations and the precision ofrop.

— Function: int **mpfr_mul_2exp** (`mpfr_t rop, mpfr_t op1, unsigned long int op2, mp_rnd_t rnd`)

— Function: int**mpfr_div_2exp** (`mpfr_t rop, mpfr_t op1, unsigned long int op2, mp_rnd_t rnd`)

— Function: int

See

`mpfr_mul_2ui`

and`mpfr_div_2ui`

. These functions are only kept for compatibility with MPF.

Some applications use a stack to handle the memory and their objects. However, the MPFR memory design is not well suited for such a thing. So that such applications are able to use MPFR, an auxiliary memory interface has been created: the Custom Interface.

The following interface allows them to use MPFR in two ways:

- Either they directly store the MPFR FP number as a
`mpfr_t`

on the stack. - Either they store their own representation of a FP number on the
stack and construct a new temporary
`mpfr_t`

each time it is needed.

Each function is this interface is also implemented as a macro for efficiency reasons.

Note 1: MPFR functions may still initialize temporary FP numbers using standard mpfr_init. See Custom Allocation (GNU MP).

Note 2: MPFR functions may use the cached functions (mpfr_const_pi for
example), even if they are not explicitly called. You have to call
`mpfr_free_cache`

each time you garbage the memory iff mpfr_init, through
GMP Custom Allocation, allocates its memory on the application stack.

Note 3: This interface is preliminary.

— Function: size_t **mpfr_custom_get_size** (`mp_prec_t prec`)

Return the needed size in bytes to store the mantissa of a FP number of precision

prec.

— Function: void **mpfr_custom_init** (`void *mantissa, mp_prec_t prec`)

Initialize a mantissa of precision

prec.mantissamust be an area of`mpfr_custom_get_size (prec)`

bytes at least and be suitably aligned for an array of`mp_limb_t`

.

— Function: void **mpfr_custom_init_set** (`mpfr_t x, int kind, mp_exp_t exp, mp_prec_t prec, void *mantissa`)

Perform a dummy initialization of a

`mpfr_t`

and set it to:In all cases, it uses

- if
`ABS(kind) == MPFR_NAN_KIND`

,xis set to NaN;- if
`ABS(kind) == MPFR_INF_KIND`

,xis set to the infinity of sign`sign(kind)`

;- if
`ABS(kind) == MPFR_ZERO_KIND`

,xis set to the zero of sign`sign(kind)`

;- if
`ABS(kind) == MPFR_REGULAR_KIND`

,xis set to a regular number:`x = sign(kind)*mantissa*2^exp`

mantissadirectly for further computing involvingx. It will not allocate anything. A FP number initialized with this function cannot be resized using`mpfr_set_prec`

, or cleared using`mpfr_clear`

!mantissamust have been initialized with`mpfr_custom_init`

using the same precisionprec.

— Function: int **mpfr_custom_get_kind** (`mpfr_t x`)

Return the current kind of a

`mpfr_t`

as used by`mpfr_custom_init_set`

. The behavior of this function for any`mpfr_t`

not initialized with`mpfr_custom_init_set`

is undefined.

— Function: void * **mpfr_custom_get_mantissa** (`mpfr_t x`)

Return a pointer to the mantissa used by a

`mpfr_t`

initialized with`mpfr_custom_init_set`

. The behavior of this function for any`mpfr_t`

not initialized with`mpfr_custom_init_set`

is undefined.

— Function: mp_exp_t **mpfr_custom_get_exp** (`mpfr_t x`)

Return the exponent of

x, assuming thatxis a non-zero ordinary number. The return value for NaN, Infinity or Zero is unspecified but doesn't produce any trap. The behavior of this function for any`mpfr_t`

not initialized with`mpfr_custom_init_set`

is undefined.

— Function: void **mpfr_custom_move** (`mpfr_t x, void *new_position`)

Inform MPFR that the mantissa has moved due to a garbage collect and update its new position to

`new_position`

. However the application has to move the mantissa and the`mpfr_t`

itself. The behavior of this function for any`mpfr_t`

not initialized with`mpfr_custom_init_set`

is undefined.

See the test suite for examples.

The following types and
functions were mainly designed for the implementation of `mpfr`

,
but may be useful for users too.
However no upward compatibility is guaranteed.
You may need to include `mpfr-impl.h` to use them.

The `mpfr_t`

type consists of four fields.

- The
`_mpfr_prec`

field is used to store the precision of the variable (in bits); this is not less than`MPFR_PREC_MIN`

. - The
`_mpfr_sign`

field is used to store the sign of the variable. - The
`_mpfr_exp`

field stores the exponent. An exponent of 0 means a radix point just above the most significant limb. Non-zero values n are a multiplier 2^n relative to that point. A NaN, an infinity and a zero are indicated by a special value of the exponent. - Finally, the
`_mpfr_d`

is a pointer to the limbs, least significant limbs stored first. The number of limbs in use is controlled by`_mpfr_prec`

, namely ceil(`_mpfr_prec`

/`mp_bits_per_limb`

). Non-singular values always have the most significant bit of the most significant limb set to 1. When the precision does not correspond to a whole number of limbs, the excess bits at the low end of the data are zero.

— Function: int **mpfr_can_round** (`mpfr_t b, mp_exp_t err, mp_rnd_t rnd1, mp_rnd_t rnd2, mp_prec_t prec`)

Assuming

bis an approximation of an unknown numberxin the directionrnd1with error at most two to the power E(b)-errwhere E(b) is the exponent ofb, return a non-zero value if one is able to round correctlyxto precisionprecwith the directionrnd2, and 0 otherwise (including for NaN and Inf). This functiondoes not modifyits arguments.

— Function: double **mpfr_get_d1** (`mpfr_t op`)

Convert

opto a`double`

, using the default MPFR rounding mode (see function`mpfr_set_default_rounding_mode`

). This function is obsolete.

The main developers consist of Guillaume Hanrot, Vincent Lefèvre, Patrick Pélissier and Paul Zimmermann.

We would like to thank Jean-Michel Muller and Joris van der Hoeven for very fruitful discussions at the beginning of that project, Torbjörn Granlund and Kevin Ryde for their help about design issues, and Nathalie Revol for her careful reading of a previous version of this documentation. Kevin Ryde did a tremendous job for the portability of MPFR, and integrating it into GMP 4.x; alas the GMP developers decided in January 2004 not to include MPFR any more.

Sylvie Boldo from ENS-Lyon, France,
contributed the functions `mpfr_agm`

and `mpfr_log`

.
Emmanuel Jeandel, from ENS-Lyon too,
contributed the generic hypergeometric code in
`generic.c`

, as well as the `mpfr_exp3`

,
a first implementation of the sine and cosine,
and improved versions of
`mpfr_const_log2`

and `mpfr_const_pi`

.
Mathieu Dutour contributed the functions `mpfr_atan`

and `mpfr_asin`

,
and a previous version of `mpfr_gamma`

;
David Daney contributed the hyperbolic and inverse hyperbolic functions,
the base-2 exponential, and the factorial function. Fabrice Rouillier
contributed the original version of `mul_ui.c`, the `gmp_op.c`
file, and helped to the Windows porting.
Jean-Luc Rémy contributed the `mpfr_zeta`

code.
Ludovic Meunier helped in the design of the `mpfr_erf`

code.
Damien Stehlé contributed the `mpfr_get_ld_2exp`

function.

The development of the MPFR library would not have been possible without the continuous support of INRIA, and of the LORIA and LIP laboratories. In particular the main authors were or are members of the PolKA, Spaces, Cacao project-teams at LORIA (Nancy, France) and of the Arenaire project-team at LIP (Lyon, France). The development of MPFR was also supported by a grant (202F0659 00 MPN 121) from the Conseil Régional de Lorraine in 2002.

- Torbjörn Granlund, "GNU MP: The GNU Multiple Precision Arithmetic Library", version 4.1.2, 2002.
- IEEE standard for binary floating-point arithmetic, Technical Report ANSI-IEEE Standard 754-1985, New York, 1985. Approved March 21, 1985: IEEE Standards Board; approved July 26, 1985: American National Standards Institute, 18 pages.
- Donald E. Knuth, "The Art of Computer Programming", vol 2, "Seminumerical Algorithms", 2nd edition, Addison-Wesley, 1981.
- Jean-Michel Muller, "Elementary Functions, Algorithms and Implementation", Birkhauser, Boston, 1997.

Version 1.2, November 2002

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- Accuracy: MPFR Interface
- Advanced functions: Advanced Functions
- Arithmetic functions: Basic Arithmetic Functions
- Assignment functions: Assignment Functions
- Basic arithmetic functions: Basic Arithmetic Functions
- Combined initialization and assignment functions: Combined Initialization and Assignment Functions
- Comparison functions: Comparison Functions
- Compatibility with MPF: Compatibility with MPF
- Conditions for copying MPFR: Copying
- Conversion functions: Conversion Functions
- Copying conditions: Copying
- Custom interface: Custom Interface
- Exception related functions: Exception Related Functions
- FDL, GNU Free Documentation License: GNU Free Documentation License
- Float arithmetic functions: Basic Arithmetic Functions
- Float comparisons functions: Comparison Functions
- Float functions: MPFR Interface
- Float input and output functions: Input and Output Functions
- Floating-point functions: MPFR Interface
- Floating-point number: MPFR Basics
- GNU Free Documentation License: GNU Free Documentation License
- I/O functions: Input and Output Functions
- Initialization functions: Initialization Functions
- Input functions: Input and Output Functions
- Installation: Installing MPFR
- Integer related functions: Integer Related Functions
- Internals: Internals
- Limb: MPFR Basics
- Miscellaneous float functions: Miscellaneous Functions
`mpfr.h`: MPFR Basics- Output functions: Input and Output Functions
- Precision: MPFR Interface
- Precision: MPFR Basics
- Reporting bugs: Reporting Bugs
- Rounding mode related functions: Rounding Mode Related Functions
- Rounding Modes: MPFR Basics
- Special functions: Special Functions

`mp_prec_t`

: MPFR Basics`mp_rnd_t`

: MPFR Basics`mpfr_abs`

: Basic Arithmetic Functions`mpfr_acos`

: Special Functions`mpfr_acosh`

: Special Functions`mpfr_add`

: Basic Arithmetic Functions`mpfr_add_q`

: Basic Arithmetic Functions`mpfr_add_si`

: Basic Arithmetic Functions`mpfr_add_ui`

: Basic Arithmetic Functions`mpfr_add_z`

: Basic Arithmetic Functions`mpfr_agm`

: Special Functions`mpfr_asin`

: Special Functions`mpfr_asinh`

: Special Functions`mpfr_atan`

: Special Functions`mpfr_atan2`

: Special Functions`mpfr_atanh`

: Special Functions`mpfr_can_round`

: Internals`mpfr_cbrt`

: Basic Arithmetic Functions`mpfr_ceil`

: Integer Related Functions`mpfr_check_range`

: Exception Related Functions`mpfr_clear`

: Initialization Functions`mpfr_clear_erangeflag`

: Exception Related Functions`mpfr_clear_flags`

: Exception Related Functions`mpfr_clear_inexflag`

: Exception Related Functions`mpfr_clear_nanflag`

: Exception Related Functions`mpfr_clear_overflow`

: Exception Related Functions`mpfr_clear_underflow`

: Exception Related Functions`mpfr_clears`

: Advanced Functions`mpfr_cmp`

: Comparison Functions`mpfr_cmp_d`

: Comparison Functions`mpfr_cmp_f`

: Comparison Functions`mpfr_cmp_ld`

: Comparison Functions`mpfr_cmp_q`

: Comparison Functions`mpfr_cmp_si`

: Comparison Functions`mpfr_cmp_si_2exp`

: Comparison Functions`mpfr_cmp_ui`

: Comparison Functions`mpfr_cmp_ui_2exp`

: Comparison Functions`mpfr_cmp_z`

: Comparison Functions`mpfr_cmpabs`

: Comparison Functions`mpfr_const_catalan`

: Special Functions`mpfr_const_euler`

: Special Functions`mpfr_const_log2`

: Special Functions`mpfr_const_pi`

: Special Functions`mpfr_copysign`

: Miscellaneous Functions`mpfr_cos`

: Special Functions`mpfr_cosh`

: Special Functions`mpfr_cot`

: Special Functions`mpfr_coth`

: Special Functions`mpfr_csc`

: Special Functions`mpfr_csch`

: Special Functions`mpfr_custom_get_exp`

: Custom Interface`mpfr_custom_get_kind`

: Custom Interface`mpfr_custom_get_mantissa`

: Custom Interface`mpfr_custom_get_size`

: Custom Interface`mpfr_custom_init`

: Custom Interface`mpfr_custom_init_set`

: Custom Interface`mpfr_custom_move`

: Custom Interface`MPFR_DECL_INIT`

: Advanced Functions`mpfr_dim`

: Basic Arithmetic Functions`mpfr_div`

: Basic Arithmetic Functions`mpfr_div_2exp`

: Compatibility with MPF`mpfr_div_2si`

: Basic Arithmetic Functions`mpfr_div_2ui`

: Basic Arithmetic Functions`mpfr_div_q`

: Basic Arithmetic Functions`mpfr_div_si`

: Basic Arithmetic Functions`mpfr_div_ui`

: Basic Arithmetic Functions`mpfr_div_z`

: Basic Arithmetic Functions`mpfr_eint`

: Special Functions`mpfr_eq`

: Compatibility with MPF`mpfr_equal_p`

: Comparison Functions`mpfr_erangeflag_p`

: Exception Related Functions`mpfr_erf`

: Special Functions`mpfr_erfc`

: Special Functions`mpfr_exp`

: Special Functions`mpfr_exp10`

: Special Functions`mpfr_exp2`

: Special Functions`mpfr_expm1`

: Special Functions`mpfr_fac_ui`

: Special Functions`mpfr_fits_intmax_p`

: Conversion Functions`mpfr_fits_sint_p`

: Conversion Functions`mpfr_fits_slong_p`

: Conversion Functions`mpfr_fits_sshort_p`

: Conversion Functions`mpfr_fits_uint_p`

: Conversion Functions`mpfr_fits_uintmax_p`

: Conversion Functions`mpfr_fits_ulong_p`

: Conversion Functions`mpfr_fits_ushort_p`

: Conversion Functions`mpfr_floor`

: Integer Related Functions`mpfr_fma`

: Special Functions`mpfr_fms`

: Special Functions`mpfr_frac`

: Integer Related Functions`mpfr_free_cache`

: Special Functions`mpfr_free_str`

: Conversion Functions`mpfr_gamma`

: Special Functions`mpfr_get_d`

: Conversion Functions`mpfr_get_d1`

: Internals`mpfr_get_d_2exp`

: Conversion Functions`mpfr_get_decimal64`

: Conversion Functions`mpfr_get_default_prec`

: Initialization Functions`mpfr_get_default_rounding_mode`

: Rounding Mode Related Functions`mpfr_get_emax`

: Exception Related Functions`mpfr_get_emax_max`

: Exception Related Functions`mpfr_get_emax_min`

: Exception Related Functions`mpfr_get_emin`

: Exception Related Functions`mpfr_get_emin_max`

: Exception Related Functions`mpfr_get_emin_min`

: Exception Related Functions`mpfr_get_exp`

: Miscellaneous Functions`mpfr_get_f`

: Conversion Functions`mpfr_get_ld`

: Conversion Functions`mpfr_get_ld_2exp`

: Conversion Functions`mpfr_get_patches`

: Miscellaneous Functions`mpfr_get_prec`

: Initialization Functions`mpfr_get_si`

: Conversion Functions`mpfr_get_sj`

: Conversion Functions`mpfr_get_str`

: Conversion Functions`mpfr_get_ui`

: Conversion Functions`mpfr_get_uj`

: Conversion Functions`mpfr_get_version`

: Miscellaneous Functions`mpfr_get_z`

: Conversion Functions`mpfr_get_z_exp`

: Conversion Functions`mpfr_greater_p`

: Comparison Functions`mpfr_greaterequal_p`

: Comparison Functions`mpfr_hypot`

: Special Functions`mpfr_inexflag_p`

: Exception Related Functions`mpfr_inf_p`

: Comparison Functions`mpfr_init`

: Initialization Functions`mpfr_init2`

: Initialization Functions`mpfr_init_set`

: Combined Initialization and Assignment Functions`mpfr_init_set_d`

: Combined Initialization and Assignment Functions`mpfr_init_set_f`

: Combined Initialization and Assignment Functions`mpfr_init_set_ld`

: Combined Initialization and Assignment Functions`mpfr_init_set_q`

: Combined Initialization and Assignment Functions`mpfr_init_set_si`

: Combined Initialization and Assignment Functions`mpfr_init_set_str`

: Combined Initialization and Assignment Functions`mpfr_init_set_ui`

: Combined Initialization and Assignment Functions`mpfr_init_set_z`

: Combined Initialization and Assignment Functions`mpfr_inits`

: Advanced Functions`mpfr_inits2`

: Advanced Functions`mpfr_inp_str`

: Input and Output Functions`mpfr_integer_p`

: Integer Related Functions`mpfr_j0`

: Special Functions`mpfr_j1`

: Special Functions`mpfr_jn`

: Special Functions`mpfr_less_p`

: Comparison Functions`mpfr_lessequal_p`

: Comparison Functions`mpfr_lessgreater_p`

: Comparison Functions`mpfr_lgamma`

: Special Functions`mpfr_lngamma`

: Special Functions`mpfr_log`

: Special Functions`mpfr_log10`

: Special Functions`mpfr_log1p`

: Special Functions`mpfr_log2`

: Special Functions`mpfr_max`

: Miscellaneous Functions`mpfr_min`

: Miscellaneous Functions`mpfr_mul`

: Basic Arithmetic Functions`mpfr_mul_2exp`

: Compatibility with MPF`mpfr_mul_2si`

: Basic Arithmetic Functions`mpfr_mul_2ui`

: Basic Arithmetic Functions`mpfr_mul_q`

: Basic Arithmetic Functions`mpfr_mul_si`

: Basic Arithmetic Functions`mpfr_mul_ui`

: Basic Arithmetic Functions`mpfr_mul_z`

: Basic Arithmetic Functions`mpfr_nan_p`

: Comparison Functions`mpfr_nanflag_p`

: Exception Related Functions`mpfr_neg`

: Basic Arithmetic Functions`mpfr_nextabove`

: Miscellaneous Functions`mpfr_nextbelow`

: Miscellaneous Functions`mpfr_nexttoward`

: Miscellaneous Functions`mpfr_number_p`

: Comparison Functions`mpfr_out_str`

: Input and Output Functions`mpfr_overflow_p`

: Exception Related Functions`mpfr_pow`

: Basic Arithmetic Functions`mpfr_pow_si`

: Basic Arithmetic Functions`mpfr_pow_ui`

: Basic Arithmetic Functions`mpfr_pow_z`

: Basic Arithmetic Functions`mpfr_prec_round`

: Rounding Mode Related Functions`mpfr_print_rnd_mode`

: Rounding Mode Related Functions`mpfr_random`

: Miscellaneous Functions`mpfr_random2`

: Miscellaneous Functions`mpfr_reldiff`

: Compatibility with MPF`mpfr_remainder`

: Integer Related Functions`mpfr_remquo`

: Integer Related Functions`mpfr_rint`

: Integer Related Functions`mpfr_rint_ceil`

: Integer Related Functions`mpfr_rint_floor`

: Integer Related Functions`mpfr_rint_round`

: Integer Related Functions`mpfr_rint_trunc`

: Integer Related Functions`mpfr_root`

: Basic Arithmetic Functions`mpfr_round`

: Integer Related Functions`mpfr_round_prec`

: Rounding Mode Related Functions`mpfr_sec`

: Special Functions`mpfr_sech`

: Special Functions`mpfr_set`

: Assignment Functions`mpfr_set_d`

: Assignment Functions`mpfr_set_decimal64`

: Assignment Functions`mpfr_set_default_prec`

: Initialization Functions`mpfr_set_default_rounding_mode`

: Rounding Mode Related Functions`mpfr_set_emax`

: Exception Related Functions`mpfr_set_emin`

: Exception Related Functions`mpfr_set_erangeflag`

: Exception Related Functions`mpfr_set_exp`

: Miscellaneous Functions`mpfr_set_f`

: Assignment Functions`mpfr_set_inexflag`

: Exception Related Functions`mpfr_set_inf`

: Assignment Functions`mpfr_set_ld`

: Assignment Functions`mpfr_set_nan`

: Assignment Functions`mpfr_set_nanflag`

: Exception Related Functions`mpfr_set_overflow`

: Exception Related Functions`mpfr_set_prec`

: Initialization Functions`mpfr_set_prec_raw`

: Compatibility with MPF`mpfr_set_q`

: Assignment Functions`mpfr_set_si`

: Assignment Functions`mpfr_set_si_2exp`

: Assignment Functions`mpfr_set_sj`

: Assignment Functions`mpfr_set_sj_2exp`

: Assignment Functions`mpfr_set_str`

: Assignment Functions`mpfr_set_ui`

: Assignment Functions`mpfr_set_ui_2exp`

: Assignment Functions`mpfr_set_uj`

: Assignment Functions`mpfr_set_uj_2exp`

: Assignment Functions`mpfr_set_underflow`

: Exception Related Functions`mpfr_set_z`

: Assignment Functions`mpfr_setsign`

: Miscellaneous Functions`mpfr_sgn`

: Comparison Functions`mpfr_si_div`

: Basic Arithmetic Functions`mpfr_si_sub`

: Basic Arithmetic Functions`mpfr_signbit`

: Miscellaneous Functions`mpfr_sin`

: Special Functions`mpfr_sin_cos`

: Special Functions`mpfr_sinh`

: Special Functions`mpfr_sqr`

: Basic Arithmetic Functions`mpfr_sqrt`

: Basic Arithmetic Functions`mpfr_sqrt_ui`

: Basic Arithmetic Functions`mpfr_strtofr`

: Assignment Functions`mpfr_sub`

: Basic Arithmetic Functions`mpfr_sub_q`

: Basic Arithmetic Functions`mpfr_sub_si`

: Basic Arithmetic Functions`mpfr_sub_ui`

: Basic Arithmetic Functions`mpfr_sub_z`

: Basic Arithmetic Functions`mpfr_subnormalize`

: Exception Related Functions`mpfr_sum`

: Special Functions`mpfr_swap`

: Assignment Functions`mpfr_t`

: MPFR Basics`mpfr_tan`

: Special Functions`mpfr_tanh`

: Special Functions`mpfr_trunc`

: Integer Related Functions`mpfr_ui_div`

: Basic Arithmetic Functions`mpfr_ui_pow`

: Basic Arithmetic Functions`mpfr_ui_pow_ui`

: Basic Arithmetic Functions`mpfr_ui_sub`

: Basic Arithmetic Functions`mpfr_underflow_p`

: Exception Related Functions`mpfr_unordered_p`

: Comparison Functions`mpfr_urandomb`

: Miscellaneous Functions`MPFR_VERSION`

: Miscellaneous Functions`MPFR_VERSION_MAJOR`

: Miscellaneous Functions`MPFR_VERSION_MINOR`

: Miscellaneous Functions`MPFR_VERSION_NUM`

: Miscellaneous Functions`MPFR_VERSION_PATCHLEVEL`

: Miscellaneous Functions`MPFR_VERSION_STRING`

: Miscellaneous Functions`mpfr_y0`

: Special Functions`mpfr_y1`

: Special Functions`mpfr_yn`

: Special Functions`mpfr_zero_p`

: Comparison Functions`mpfr_zeta`

: Special Functions`mpfr_zeta_ui`

: Special Functions