[Chapter 3] 3.2.149 sin
Author: Larry Wall, Tom Christiansen & Randal L. Schwartz
Date: 1999-07-02T01:54:10Z

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| Chapter 3 Functions |

### 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])) }

3.2.148 shutdown |  | 3.2.150 sleep