# isfinite > Test if a double-precision floating-point numeric value is finite.
## Usage ```javascript var isfinite = require( '@stdlib/math/base/assert/is-finite' ); ``` #### isfinite( x ) Tests if a double-precision floating-point `numeric` value is finite. ```javascript var bool = isfinite( 3.14 ); // returns true bool = isfinite( Infinity ); // returns false bool = isfinite( -Infinity ); // returns false bool = isfinite( NaN ); // returns false ```
## Examples ```javascript var PINF = require( '@stdlib/constants/float64/pinf' ); var NINF = require( '@stdlib/constants/float64/ninf' ); var isfinite = require( '@stdlib/math/base/assert/is-finite' ); var bool = isfinite( 5.0 ); // returns true bool = isfinite( -2.0e64 ); // returns true bool = isfinite( PINF ); // returns false bool = isfinite( NINF ); // returns false bool = isfinite( NaN ); // returns false ```