| |
| /* @(#)z_floor.c 1.0 98/08/13 */ |
| |
| /* |
| FUNCTION |
| <<floor>>, <<floorf>>, <<ceil>>, <<ceilf>>---floor and ceiling |
| INDEX |
| floor |
| INDEX |
| floorf |
| INDEX |
| ceil |
| INDEX |
| ceilf |
| |
| ANSI_SYNOPSIS |
| #include <math.h> |
| double floor(double <[x]>); |
| float floorf(float <[x]>); |
| double ceil(double <[x]>); |
| float ceilf(float <[x]>); |
| |
| TRAD_SYNOPSIS |
| #include <math.h> |
| double floor(<[x]>) |
| double <[x]>; |
| float floorf(<[x]>) |
| float <[x]>; |
| double ceil(<[x]>) |
| double <[x]>; |
| float ceilf(<[x]>) |
| float <[x]>; |
| |
| DESCRIPTION |
| <<floor>> and <<floorf>> find |
| @tex |
| $\lfloor x \rfloor$, |
| @end tex |
| the nearest integer less than or equal to <[x]>. |
| <<ceil>> and <<ceilf>> find |
| @tex |
| $\lceil x\rceil$, |
| @end tex |
| the nearest integer greater than or equal to <[x]>. |
| |
| RETURNS |
| <<floor>> and <<ceil>> return the integer result as a double. |
| <<floorf>> and <<ceilf>> return the integer result as a float. |
| |
| PORTABILITY |
| <<floor>> and <<ceil>> are ANSI. |
| <<floorf>> and <<ceilf>> are extensions. |
| |
| */ |
| |
| /***************************************************************** |
| * floor |
| * |
| * Input: |
| * x - floating point value |
| * |
| * Output: |
| * Smallest integer less than x. |
| * |
| * Description: |
| * This routine returns the smallest integer less than x. |
| * |
| *****************************************************************/ |
| |
| #include "fdlibm.h" |
| #include "zmath.h" |
| |
| #ifndef _DOUBLE_IS_32BITS |
| |
| double |
| _DEFUN (floor, (double), |
| double x) |
| { |
| double f, y; |
| |
| if (x > -1.0 && x < 1.0) |
| return (x >= 0 ? 0 : -1.0); |
| |
| y = modf (x, &f); |
| |
| if (y == 0.0) |
| return (x); |
| |
| return (x >= 0 ? f : f - 1.0); |
| } |
| |
| #endif /* _DOUBLE_IS_32BITS */ |