JavaScript: Initialize an array containing the numbers in the specified range where start and end are inclusive with their common difference step

JavaScript fundamental (ES6 Syntax): Exercise-54 with Solution

Array of Numbers in Specified Range

Write a JavaScript program to initialize an array containing numbers in the specified range. Start and end are inclusive of their common point of difference.

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

Sample Solution:

JavaScript Code:

//#Source https://bit.ly/2neWfJ2
// Define a function 'initialize_Array_With_Range' to create an array filled with a range of numbers.
const initialize_Array_With_Range = (end, start = 0, step = 1) =>
  // Create an array with the length calculated based on the range and map each index to its corresponding value based on the step.
  Array.from({ length: Math.ceil((end + 1 - start) / step) }).map((v, i) => i * step + start);

// Test cases
console.log(initialize_Array_With_Range(5)); // Output: [ 0, 1, 2, 3, 4, 5 ]
console.log(initialize_Array_With_Range(8, 3)); // Output: [ 3, 4, 5, 6, 7, 8 ]
console.log(initialize_Array_With_Range(6, 0, 2)); // Output: [ 0, 2, 4, 6 ]

Output:

[0,1,2,3,4,5]
[3,4,5,6,7,8]
[0,2,4,6]

Visual Presentation:

Flowchart:

Live Demo:

See the Pen javascript-basic-exercise-1-54 by w3resource (@w3resource) on CodePen.

For more Practice: Solve these Related Problems:

• Write a JavaScript program that creates an array of consecutive numbers within a specified inclusive range.
• Write a JavaScript function that generates an array from a start number to an end number using Array.from().
• Write a JavaScript program that validates range inputs and returns an array containing each number in that interval.

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