Test whether two complex numbers are approximately equal within a specified number of ULPs (units in the last place).
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> Test whether two complex numbers are approximately equal within a specified number of ULPs (units in the last place).
``bash`
npm install @stdlib/complex-base-assert-is-almost-equal
`javascript`
var isAlmostEqual = require( '@stdlib/complex-base-assert-is-almost-equal' );
#### isAlmostEqual( z1, z2, maxULP )
Tests whether two complex numbers are approximately equal within a specified number of ULPs (units in the last place).
`javascript
var EPS = require( '@stdlib/constants-float64-eps' );
var Complex128 = require( '@stdlib/complex-float64-ctor' );
var z1 = new Complex128( 1.0, 3.0 );
var z2 = new Complex128( 1.0+EPS, 3.0 );
var out = isAlmostEqual( z1, z2, 0 );
// returns false
out = isAlmostEqual( z1, z2, 1 );
// returns true
`
The function returns false if either input value has a NaN real or imaginary component.
`javascript
var Complex64 = require( '@stdlib/complex-float32-ctor' );
var z1 = new Complex64( NaN, 3.0 );
var z2 = new Complex64( 1.0, 3.0 );
var out = isAlmostEqual( z1, z2, 1 );
// returns false
out = isAlmostEqual( z2, z1, 1 );
// returns false
z1 = new Complex64( NaN, NaN );
z2 = new Complex64( NaN, NaN );
out = isAlmostEqual( z1, z2, 1 );
// returns false
`
The function does not distinguish between -0 and +0, treating them as equal.
`javascript
var Complex128 = require( '@stdlib/complex-float64-ctor' );
var Complex64 = require( '@stdlib/complex-float32-ctor' );
var z1 = new Complex128( 0.0, 0.0 );
var z2 = new Complex64( -0.0, -0.0 );
var out = isAlmostEqual( z1, z2, 0 );
// returns true
`
`javascript
var EPS = require( '@stdlib/constants-float64-eps' );
var Complex128 = require( '@stdlib/complex-float64-ctor' );
var isAlmostEqual = require( '@stdlib/complex-base-assert-is-almost-equal' );
var z1 = new Complex128( 1.0, 3.0+EPS );
var z2 = new Complex128( 1.0+EPS, 3.0 );
console.log( isAlmostEqual( z1, z2, 1 ) );
// => true
z1 = new Complex128( 1.0, 3.0+EPS );
z2 = new Complex128( 1.0+EPS+EPS, 3.0 );
console.log( isAlmostEqual( z1, z2, 1 ) );
// => false
z1 = new Complex128( 0.0, 0.0 );
z2 = new Complex128( -0.0, 0.0 );
console.log( isAlmostEqual( z1, z2, 0 ) );
// => true
z1 = new Complex128( NaN, 0.0 );
z2 = new Complex128( 1.0, 0.0 );
console.log( isAlmostEqual( z1, z2, 1 ) );
// => false
`
*
This package is part of [stdlib][stdlib], a standard library for JavaScript and Node.js, 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][stdlib], see the main project [repository][stdlib].
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