[Gmpcommit] /var/hg/gmp: Further clarify mpf_eq documentation.
mercurial at gmplib.org
mercurial at gmplib.org
Tue Apr 14 10:46:29 UTC 2015
details: /var/hg/gmp/rev/785d66ddd532
changeset: 16574:785d66ddd532
user: Torbjorn Granlund <torbjorng at google.com>
date: Tue Apr 14 12:45:32 2015 +0200
description:
Further clarify mpf_eq documentation.
diffstat:
doc/gmp.texi  14 +++++
1 files changed, 5 insertions(+), 9 deletions()
diffs (25 lines):
diff r c272212664b5 r 785d66ddd532 doc/gmp.texi
 a/doc/gmp.texi Mon Apr 13 23:14:29 2015 +0200
+++ b/doc/gmp.texi Tue Apr 14 12:45:32 2015 +0200
@@ 4968,16 +4968,12 @@
@end deftypefun
@deftypefun int mpf_eq (const mpf_t @var{op1}, const mpf_t @var{op2}, mp_bitcnt_t op3)
+ at strong{This function is mathematically illdefined and should not be used.}
+
Return nonzero if the first @var{op3} bits of @var{op1} and @var{op2} are
equal, zero otherwise. I.e., test if @var{op1} and @var{op2} are approximately
equal.

Caution 1: All version of GMP up to version 4.2.4 compared just whole limbs,
meaning sometimes more than @var{op3} bits, sometimes fewer.

Caution 2: This function will consider XXX11...111 and XX100...000 different,
even if ... is replaced by a semiinfinite number of bits. Such numbers are
really just one ulp off, and should be considered equal.
+equal, zero otherwise. Note that numbers like e.g., 256 (binary 100000000) and
+255 (binary 11111111) will never be equal by this function's measure, and
+furthermore that 0 will only be equal to itself.
@end deftypefun
@deftypefun void mpf_reldiff (mpf_t @var{rop}, const mpf_t @var{op1}, const mpf_t @var{op2})
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