atan(), atanf()

Compute the arctangent of an angle

Synopsis:

#include <math.h>

double atan( double x );

float atanf( float x );

Library:

libm

Description:

These functions compute the arctangent (specified in radians) of x.

Returns:

The arctangent, in the range (-PI/2, PI/2).

Examples:

#include <stdio.h>
#include <math.h>
#include <stdlib.h>

int main( void )
{
    printf( "%f\n", atan(.5) );
    return EXIT_SUCCESS;
}

produces the output:

0.463648

Classification:

ANSI

See also:

acos(), asin(), atan2()