| .\" Copyright 2003 Walter Harms, Andries Brouwer |
| .\" and Copyright 2008, Linux Foundation, written by Michael Kerrisk |
| .\" <mtk.manpages@gmail.com> |
| .\" |
| .\" %%%LICENSE_START(GPL_NOVERSION_ONELINE) |
| .\" Distributed under GPL |
| .\" %%%LICENSE_END |
| .\" |
| .TH FDIM 3 2015-04-19 "" "Linux Programmer's Manual" |
| .SH NAME |
| fdim, fdimf, fdiml \- positive difference |
| .SH SYNOPSIS |
| .B #include <math.h> |
| .sp |
| .BI "double fdim(double " x ", double " y ); |
| .br |
| .BI "float fdimf(float " x ", float " y ); |
| .br |
| .BI "long double fdiml(long double " x ", long double " y ); |
| .sp |
| Link with \fI\-lm\fP. |
| .sp |
| .in -4n |
| Feature Test Macro Requirements for glibc (see |
| .BR feature_test_macros (7)): |
| .in |
| .sp |
| .ad l |
| .BR fdimf (), |
| .BR fdiml (): |
| .RS 4 |
| _XOPEN_SOURCE\ >=\ 600 || _ISOC99_SOURCE || |
| _POSIX_C_SOURCE\ >=\ 200112L; |
| .br |
| or |
| .I cc\ -std=c99 |
| .RE |
| .ad |
| .SH DESCRIPTION |
| These functions return the positive difference, max(\fIx\fP-\fIy\fP,0), |
| between their arguments. |
| .SH RETURN VALUE |
| On success, these functions return the positive difference. |
| |
| If |
| .I x |
| or |
| .I y |
| is a NaN, a NaN is returned. |
| |
| If the result overflows, |
| a range error occurs, |
| and the functions return |
| .BR HUGE_VAL , |
| .BR HUGE_VALF , |
| or |
| .BR HUGE_VALL , |
| respectively. |
| .SH ERRORS |
| See |
| .BR math_error (7) |
| for information on how to determine whether an error has occurred |
| when calling these functions. |
| .PP |
| The following errors can occur: |
| .TP |
| Range error: result overflow |
| .\" .I errno |
| .\" is set to |
| .\" .BR ERANGE . |
| An overflow floating-point exception |
| .RB ( FE_OVERFLOW ) |
| is raised. |
| .PP |
| These functions do not set |
| .IR errno . |
| .\" FIXME . Is it intentional that these functions do not set errno? |
| .\" Bug raised: http://sources.redhat.com/bugzilla/show_bug.cgi?id=6796 |
| .SH VERSIONS |
| These functions first appeared in glibc in version 2.1. |
| .SH ATTRIBUTES |
| For an explanation of the terms used in this section, see |
| .BR attributes (7). |
| .TS |
| allbox; |
| lbw24 lb lb |
| l l l. |
| Interface Attribute Value |
| T{ |
| .BR fdim (), |
| .BR fdimf (), |
| .BR fdiml () |
| T} Thread safety MT-Safe |
| .TE |
| .SH CONFORMING TO |
| C99, POSIX.1-2001, POSIX.1-2008. |
| .SH SEE ALSO |
| .BR fmax (3) |