time-to-botec/squiggle/node_modules/@stdlib/math/base/assert/is-safe-integer/README.md

isSafeInteger

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

Usage

var isSafeInteger = require( '@stdlib/math/base/assert/is-safe-integer' );

isSafeInteger( x )

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

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

Notes

• An integer valued number is "safe" when the number can be exactly represented as a double-precision floating-point number. For example,

  var MAX_SAFE_INTEGER = require( '@stdlib/constants/float64/max-safe-integer' );
  // returns 9007199254740991
  
  var x = 9007199254740992;
  // returns 9007199254740992
  
  var y = 9007199254740993;
  // returns 9007199254740992
  
  var bool = ( x === y );
  // returns true
  

  In this example, x and y should be distinct, but they are not due to constraints imposed by storing numeric values in double-precision floating-point format. "Safe" integers are thus double-precision floating-point numbers having integer values with unequivocal binary representations.

Examples

var isSafeInteger = require( '@stdlib/math/base/assert/is-safe-integer' );

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

bool = isSafeInteger( 2.0e200 );
// returns false

bool = isSafeInteger( 3.14 );
// returns false

bool = isSafeInteger( NaN );
// returns false