PHP Functions Essential Reference

sin

float sin(float num) 

Calculates the sine of a floating-point number.

Returns:

Floating-point sine value

Description:

Returns the sine for the argument passed in radians. Return values are from -1 to 1.

Version:

PHP 3, PHP 4

See also:

acos() 
asin() 
atan() 
atan2() 
cos() 
tan() 

Example:

Calculate the sine of a value

echo "The sine for the four cardinal points of a circle are:<br />\n"; echo "0 degrees: ", sin(0), "<br />\n"; echo "90 degrees: ", sin(pi() / 2), "<br />\n"; echo "180 degrees: ", sin(pi()), "<br />\n"; echo "270 degrees: ", sin(pi() + pi() / 2), "<br />\n";