difference (original) (raw)

Obtain values not present in another array.

Similar: union, intersection, difference, symmetricDifference.

function difference(x, y, fc, fm) // x: an array // y: another array // fc: compare function (a, b) // fm: map function (v, i, x)

⏱️ Compare function ⇒ O(n²).

const xarray = require('extra-array');

var x = [1, 2, 3, 4, 5]; var y = [2, 4]; xarray.difference(x, y); // → [ 1, 3, 5 ]

var y = [-2, -4]; xarray.difference(x, y); // → [ 1, 2, 3, 4, 5 ]

xarray.difference(x, y, (a, b) => Math.abs(a) - Math.abs(b)); // → [ 1, 3, 5 ]

xarray.difference(x, y, null, v => Math.abs(v)); // → [ 1, 3, 5 ]

References

• Data.List.\ : Haskell
• Data.Set.difference() : Haskell
• Set.difference() : Python
• _.difference() : Lodash
• _.differenceBy() : Lodash
• _.differenceWith() : Lodash
• Array.remove() : Sugar.js