acos (Windows CE 5.0)

Send Feedback

Developing an Application > Microsoft C Run-time Library for Windows CE > Run-time Library Reference

Calculates the arccosine.

double acos(    doublex);

Parameters

  • x
    Value between –1 and 1 whose arccosine is to be calculated.

Return Values

The acos function returns the arccosine of x in the range 0 to π radians.

If x is less than –1 or greater than 1, acos returns an indefinite (same as a quiet NaN).

Example

/* ASINCOS.C: This program prompts for a value in the range
 * -1 to 1. Input values outside this range will produce
 * _DOMAIN error messages.If a valid value is entered, the
 * program prints the arcsine and the arccosine of that value.
 */

#include <stdlib.h>

void main( void )
{
   double x, y;

   printf( "Enter a real number between -1 and 1: " );
   scanf( "%lf", &x );
   y = asin( x );
   printf( "Arcsine of %f = %f\n", x, y );
   y = acos( x );
   printf( "Arccosine of %f = %f\n", x, y );
}

Output

Enter a real number between -1 and 1: .32696
Arcsine of 0.326960 = 0.333085
Arccosine of 0.326960 = 1.237711

Requirements

OS Versions: Windows CE 2.0 and later.
Header: stdlib.h.
Link Library: coredll.dll.

See Also

asin | atan | cos | sin | tan

Send Feedback on this topic to the authors

Feedback FAQs

© 2006 Microsoft Corporation. All rights reserved.