PHP: acos() function

Description

The acos() function returns the arc cosine of a number in radians.

Version:

(PHP 4 and above)

Syntax:

acos(number)

Parameter:

Return value:

The arc cosine of a number.

Value Type: Float.

Example:

<?php
$val1= 0;
$val2 = .4;
$val3 = 1;
$val4 = 2;
$zacos1=acos($val1);
$zacos2=acos($val2);
$zacos3=acos($val3);
$zacos4=acos($val4);
echo "Arc cosine of  $val1 is $abs1<br />";
echo "Arc cosine of  $val2 is $abs1<br />";
echo "Arc cosine of  $val3 is $abs1<br />";
echo "Arc cosine of  $val4 is $abs1<br />";
?>

Sample Output:

Arc cosine of  0 is 1.5707963267949
Arc cosine of  0.4 is   1.1592794807274
Arc cosine of  1 is 0
Arc cosine of  2 is NAN

View the example in the browser

Pictorial Presentation :

See also

PHP Function Reference

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