std/collections/sliding_windows.ts

Deno standard library
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function slidingWindows
import { slidingWindows } from "https://deno.land/std@0.147.0/collections/sliding_windows.ts?s=slidingWindows";

Generates sliding views of the given array of the given size and returns a new array containing all of them.

If step is set, each window will start that many elements after the last window's start. (Default: 1)

If partial is set, windows will be generated for the last elements of the collection, resulting in some undefined values if size is greater than 1. (Default: false)

Example:

import { slidingWindows } from "https://deno.land/std@0.147.0/collections/sliding_windows.ts";
import { assertEquals } from "https://deno.land/std@0.147.0/testing/asserts.ts";
const numbers = [1, 2, 3, 4, 5];

const windows = slidingWindows(numbers, 3);
assertEquals(windows, [
  [1, 2, 3],
  [2, 3, 4],
  [3, 4, 5],
]);

const windowsWithStep = slidingWindows(numbers, 3, { step: 2 });
assertEquals(windowsWithStep, [
  [1, 2, 3],
  [3, 4, 5],
]);

const windowsWithPartial = slidingWindows(numbers, 3, { partial: true });
assertEquals(windowsWithPartial, [
  [1, 2, 3],
  [2, 3, 4],
  [3, 4, 5],
  [4, 5],
  [5],
]);

Parameters

array: readonly T[][src]
size: number[src]
optional
unnamed 2: { step?: number; partial?: boolean; }
[src]