Test if a double-precision floating-point numeric value is NaN.
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> Test if a double-precision floating-point numeric value is NaN.
``bash`
npm install @stdlib/math-base-assert-is-nan
`javascript`
var isnan = require( '@stdlib/math-base-assert-is-nan' );
#### isnan( x )
Tests if a double-precision floating-point numeric value is NaN.
`javascript`
var bool = isnan( NaN );
// returns true
`javascript
var isnan = require( '@stdlib/math-base-assert-is-nan' );
var bool = isnan( NaN );
// returns true
bool = isnan( 5.0 );
// returns false
`
*
- [@stdlib/math-base/assert/is-nanf][@stdlib/math/base/assert/is-nanf]: test if a single-precision floating-point numeric value is NaN.
*
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---
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