fmin, fminf, fminl — determine minimum of two floating-point numbers


#include <math.h>

double fmin(double x, double y);
float fminf(float x, float y);
long double fminl(long double x, long double y);

Link with -lm.

Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

fmin(), fminf(), fminl():



These functions return the lesser value of x and y.

Return Value

These functions return the minimum of x and y.

If one argument is a NaN, the other argument is returned.

If both arguments are NaN, a NaN is returned.


No errors occur.


These functions first appeared in glibc in version 2.1.


For an explanation of the terms used in this section, see attributes(7).

Interface Attribute Value
fmin(), fminf(), fminl() Thread safety MT-Safe

Conforming to

C99, POSIX.1-2001, POSIX.1-2008.

See Also

fdim(3), fmax(3)


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Referenced By


The man pages fminf(3) and fminl(3) are aliases of fmin(3).

2017-09-15 Linux Programmer's Manual