NAME

sqrt(), sqrtf() − square root functions

SYNOPSIS

#include <math.h>

double sqrt(double x);

float sqrtf(float x);

DESCRIPTION

sqrt() returns the non-negative square root of x. The value of x must not be negative. 

sqrtf() is a float version of sqrt(); it takes a float argument and returns a float result.  To use this function, compile either with the −Ae option or with the −Aa and −D_HPUX_SOURCE options.  Otherwise, the compiler promotes the float argument to double, and the function returns incorrect results. 

sqrtf() is not specified by any standard, but it is named in accordance with the conventions specified in the "Future Library Directions" section of the ANSI C standard. 

To use these functions, link in the math library by specifying −lm on the compiler or linker command line. 

RETURN VALUE

If x is +INFINITY, sqrt() returns +INFINITY. 

If x is NaN, sqrt() returns NaN. 

If x is negative, sqrt() returns NaN and sets errno to [EDOM]. 

ERRORS

If sqrt() fails, errno is set to the following value. 

[EDOM] x is negative. 

SEE ALSO

exp(3M), log(3M), pow(3M), cbrt(3M), isinf(3M), isnan(3M). 

STANDARDS CONFORMANCE

sqrt(): SVID3, XPG4.2, ANSI C

Hewlett-Packard Company  —  HP-UX Release 10.20:  July 1996