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asin(), asinf()

Compute the arcsine of an angle

Synopsis:

#include <math.h>

double asin( double x );

float asinf( float x );

Arguments:

x

The sine for which you want to find the angle.

Library:

libm

Use the -l m option to qcc to link against this library.

Description:

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

Returns:

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

If an error occurs, these functions return 0, but this is also a valid mathematical result. If you want to check for errors, set errno to 0, call the function, and then check errno again. These functions don't change errno if no errors occurred.

Examples:

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

int main( void )
{
    printf( "%f\n", asin(.5) );

    return EXIT_SUCCESS;
}

produces the output:

0.523599

Classification:

ANSI, POSIX 1003.1

See also:

acos(), atan(), atan2(), errno