sin — Calculates the sine of a floating-point number.
float num: Number for which
to find the sine
Floating-point sine value
Returns the sine for the argument passed in radians.
Return values are from -1 to 1.
Example 691. 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";
PHP Functions Essential Reference. Copyright © 2002 by New Riders Publishing
(Authors: Zak Greant, Graeme Merrall, Torben Wilson, Brett Michlitsch).
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