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If x or y is NaN, set x to NaN. Otherwise, if x is different from y, replace x by the next floating-point number (with the precision of x and the current exponent range) in the direction of y, 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.
Set rop to the minimum of op1 and op2. If op1 and op2 are both NaN, then rop is set to NaN. If op1 or op2 is NaN, then rop is set to the numeric value. If op1 and op2 are zeros of different signs, then rop is set to −0.
Set rop to the maximum of op1 and op2. If op1 and op2 are both NaN, then rop is set to NaN. If op1 or op2 is NaN, then rop is set to the numeric value. If op1 and op2 are zeros of different signs, then rop is set to +0.
Generate a uniformly distributed random float in the interval 0 <= rop < 1. More precisely, the number can be seen as a float with a random non-normalized significand and exponent 0, which is then normalized (thus if e denotes the exponent after normalization, then the least -e significant bits of the significand are always 0). Return 0, unless the exponent is not in the current exponent range, in which case rop is set to NaN and a non-zero value is returned (this should never happen in practice, except in very specific cases). The second argument is a
gmp_randstate_t
structure which should be created using the GMPgmp_randinit
function, see the GMP manual.
Generate a uniformly distributed random float in the interval 0 <= rop < 1.
This function is deprecated and will be suppressed in the next release;
mpfr_urandomb
should be used instead.
Generate a random float of at most size limbs, with long strings of zeros and ones in the binary representation. The exponent of the number is in the interval −exp to exp. 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 when size is negative. Put +0 in rop when 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’).
This function is deprecated and will be suppressed in the next release.
Get the exponent of x, assuming that x is a non-zero ordinary number and the significand is chosen in [1/2,1). The behavior for NaN, infinity or zero is undefined.
Set the exponent of x if e is in the current exponent range, and return 0 (even if x is not a non-zero ordinary number); otherwise, return a non-zero value. The significand is assumed to be in [1/2,1).
Return a non-zero value iff op has its sign bit set (i.e. if it is negative, −0, or a NaN whose representation has its sign bit set).
Set the value of rop from op, rounded toward the given direction rnd, then set (resp. clear) its sign bit if s is non-zero (resp. zero), even when op is a NaN.
Set the value of rop from op1, rounded toward the given direction rnd, then set its sign bit to that of op2 (even when op1 or op2 is a NaN). This function is equivalent to
mpfr_setsign (
rop,
op1, mpfr_signbit (
op2),
rnd)
.
Return the MPFR version, as a null-terminated string.
MPFR_VERSION
is the version of MPFR as a preprocessing constant.MPFR_VERSION_MAJOR
,MPFR_VERSION_MINOR
andMPFR_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 ofmpfr_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).
Create an integer in the same format as used by
MPFR_VERSION
from the given major, minor and patchlevel. 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
Return a null-terminated string containing the ids of the patches applied to the MPFR library (contents of the PATCHES file), 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).