[Chapter 3] 3.2.149 sin

3.2.149 sin

sin EXPR

Sorry, there's nothing wicked about this operator. It merely returns the sine of EXPR (expressed in radians). If EXPR is omitted, it returns sine of $_.

For the inverse sine operation, you may use the POSIX::asin() function, or use this relation:

sub asin { atan2($_[0], sqrt(1 - $_[0] * $_[0])) }