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isInteger

Test if a finite double-precision floating-point number is an integer.

Usage

import isInteger from 'https://cdn.jsdelivr.net/gh/stdlib-js/math-base-assert-is-integer@deno/mod.js';

isInteger( x )

Tests if a finite double-precision floating-point number is an integer.

var bool = isInteger( 1.0 );
// returns true

Notes

• The function assumes a finite number. If provided positive or negative infinity, the function will return true, when, in fact, the result is undefined. If x can be infinite, wrap the implementation as follows:

  function check( x ) {
      return (
          x < Infinity &&
          x > -Infinity &&
          isInteger( x )
      );
  }
  
  var bool = check( Infinity );
  // returns false
  
  bool = check( -Infinity );
  // returns false

Examples

import isInteger from 'https://cdn.jsdelivr.net/gh/stdlib-js/math-base-assert-is-integer@deno/mod.js';

var bool = isInteger( -5.0 );
// returns true

bool = isInteger( 3.14 );
// returns false

bool = isInteger( NaN );
// returns false

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Notice

This package is part of stdlib, a standard library with an emphasis on numerical and scientific computing. The library provides a collection of robust, high performance libraries for mathematics, statistics, streams, utilities, and more.

For more information on the project, filing bug reports and feature requests, and guidance on how to develop stdlib, see the main project repository.

Community

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License

See LICENSE.

Copyright

Copyright © 2016-2025. The Stdlib Authors.