30-seconds-of-code/snippets/initializeArrayWithRange.md

title, tags

title	tags
initializeArrayWithRange	array,math,intermediate

Initializes an array containing the numbers in the specified range where start and end are inclusive with their common difference step.

• Use Array.from() to create an array of the desired length, (end - start + 1)/step, and a map function to fill it with the desired values in the given range.
• You can omit start to use a default value of 0.
• You can omit step to use a default value of 1.

const initializeArrayWithRange = (end, start = 0, step = 1) =>
  Array.from({ length: Math.ceil((end - start + 1) / step) }, (v, i) => i * step + start);

initializeArrayWithRange(5); // [0,1,2,3,4,5]
initializeArrayWithRange(7, 3); // [3,4,5,6,7]
initializeArrayWithRange(9, 0, 2); // [0,2,4,6,8]