diff options
Diffstat (limited to 'newlib/libm/common/s_fdim.c')
| -rw-r--r-- | newlib/libm/common/s_fdim.c | 37 |
1 files changed, 36 insertions, 1 deletions
diff --git a/newlib/libm/common/s_fdim.c b/newlib/libm/common/s_fdim.c index 0010bf59d..8eb878209 100644 --- a/newlib/libm/common/s_fdim.c +++ b/newlib/libm/common/s_fdim.c @@ -3,6 +3,39 @@ * Permission to use, copy, modify, and distribute this software * is freely granted, provided that this notice is preserved. */ +/* +FUNCTION +<<fdim>>, <<fdimf>>--positive difference +INDEX + fdim +INDEX + fdimf + +ANSI_SYNOPSIS + #include <math.h> + double fdim(double <[x]>, double <[y]>); + float fdimf(float <[x]>, float <[y]>); + +DESCRIPTION +The <<fdim>> functions determine the positive difference between their +arguments, returning: +. <[x]> - <[y]> if <[x]> > <[y]>, or + @ifnottex +. +0 if <[x]> <= <[y]>, or + @end ifnottex + @tex +. +0 if <[x]> $\leq$ <[y]>, or + @end tex +. NAN if either argument is NAN. +A range error may occur. + +RETURNS +The <<fdim>> functions return the positive difference value. + +PORTABILITY +ANSI C, POSIX. + +*/ #include "fdlibm.h" @@ -17,7 +50,9 @@ #endif { int c = __fpclassifyd(x); - if (c == FP_NAN || c == FP_INFINITE) + if (c == FP_NAN) return(x); + if (__fpclassifyd(y) == FP_NAN) return(y); + if (c == FP_INFINITE) return HUGE_VAL; return x > y ? x - y : 0.0; |