Javascript Problems – Create my own Array.prototype.filter() method – myFilter()

The purpose of this exercise is to create my own Array.prototype.filter() method – myFilter().  On line 2, I add a new myFilter() method, which takes in a function as an argument, to the array object.  I loop through each item in the array that called the method, and on line 6 determine if the function has […]

Javascript Problems – Create my own Array.prototype.forEach() method – myForEach()

The purpose of this exercise is to create my own Array.prototype.forEach() method – myForEach(). According to the MDN Developers page for Array.prototype.forEach(), “The forEach() method executes a provided function once for each array element”. I use the same sample data sets as I did or the myMap() method.  Whereas myMap() modifies each element in the […]

Javascript Problems – Create my own Array.prototype.reduce() method – myReduce()

In this exercise, I create my own Array.prototype.reduce() method – myReduce().  On line 3, I add a new method to the Array object which takes in a function and an initial value.  Starting on line 5, I loop through the array that calls this method.  The function called is applied to each element, and the […]

Javascript Problems — Select only object from array

The goal of this exercise is to take an array of items: objects, arrays, numbers, strings and null, and return only true objects.  Both null and arrays are objects in Javascript, so I have to test for those specifically.  First I used the reduce method.  On line 7, I test if an item is null […]

Javascript Recursion

I’m working on some problems to help me better understand recursion.  First, I will do a function to calculate n factorial (n!). This is how Wikipedia explains factorial: In mathematics, the factorial of a non-negative integer n, denoted by n!, is the product of all positive integers less than or equal to n. For example, The example below is a good case for using a […]