M_PI_2 = Half of PI ()
M_PI_4 = One Quarter PI ()
M_1_PI =One divided by PI ()
M_2_PI = Two divided by PI ()
M_SQRTPI = Square root of PI ()
M_2_SQRTPI = Two Divided by the square root of PI ()
Using these variations:
M_PI is a constant that will produce the same value as PI (). Here is an example of how to use M_PI and it's variations:
echo M_PI;
echo "
";
echo M_2_PI * 4;
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