tan
    (PHP 3, PHP 4 )
tan -- Tangent
Description
float 
tan ( float arg)
     tan() returns the tangent of the arg 
     parameter.  The arg parameter is in radians.
    
     
Example 1. tan() example <?php
echo tan(M_PI_2); // 1
?>  |  
  | 
    
     See also atan(), sin(),
     cos() and deg2rad().