# 1/2 times π > One half times the mathematical constant [π][pi].

## Usage ```javascript var HALF_PI = require( '@stdlib/constants/float64/half-pi' ); ``` #### HALF_PI One half times the mathematical constant [π][pi]. ```javascript var bool = ( HALF_PI === 1.5707963267948966 ); // returns true ```

## Examples ```javascript var HALF_PI = require( '@stdlib/constants/float64/half-pi' ); console.log( HALF_PI ); // => 1.5707963267948966 ```

[pi]: https://en.wikipedia.org/wiki/Pi