DEV Community: Nedy Udombat

How did you set up your blog

Nedy Udombat — Wed, 11 Dec 2019 15:27:58 +0000

Hello Everyone,

I am trying to set up my blog and I want to be able to track things like reads, page visits and other metrics for analysis.

Do you mind sharing how you set up your blog, tools and technologies you used, and how you tracked analytics? Links to your blogs and links to articles where you wrote about it(if any) would be appreciated.

What advice would you give to someone leading a team of remote developers.

Nedy Udombat — Fri, 08 Nov 2019 11:33:58 +0000

Hi guys, what advice would you give to someone leading a team of remote developers scattered across the globe, and their timeline only intersects 3 hours a day.

Please share your experiences if you have any.

Explain Redux to me like I am five.

Nedy Udombat — Fri, 01 Nov 2019 15:27:43 +0000

Explain Redux to me like I am a five year old, what it is and why it is important?

Understanding JavaScript Array Series XX - Array.unshift()

Nedy Udombat — Thu, 24 Oct 2019 21:58:56 +0000

Yesterday, you asked a question saying What if I want to put back the element I have removed either from the start of the array or the end of the array?. Can't recall asking this? Check this article to refresh your memory.

Understanding JavaScript Array Series XIX - Array.shift()

Nedy Udombat ・ Oct 23 '19

#javascript #beginners #webdev

Have you heard about the Array.unshift()? No?

This method adds a new element or a bunch of elements to the start of the array and returns the new length of the array. This is the opposite of Array.shift() as it adds to the beginning of the array, while Array.shift() removes from the beginning of the array.

Can you show me the syntax? Yeah sure.

const elem = arr.unshift(item1, item2, item3, ..., itemN);

[item1, item2, item3, ..., itemN]: These are the elements to be added to the array.

[arr]: This is the array you want to add the new elements to.

[elem]: This value holds the new length of the array after the successful addition of elements to the start of the array.

Cool, it is kind of similar to array.push(), except here it adds the element from the beginning of the array. Please, can you show us an example? Sure why not.

const arr = [2, 3, 4, 5];
arr.unshift(1);
console.log(arr) // [1, 2, 3, 4, 5];

What happens if an array is passed as the argument to unshift()

const arr = [2, 3, 4, 5];
arr.unshift([0, 1]);
console.log(arr); // [[0, 1], 2, 3, 4, 5];

In this case the entire array that is passed as an argument is passed as one argument to the array.

Conclusion:

Array.push(): Add items to the end of an array.
Array.pop(): Remove items from the end of an array.
Array.unshift(): Add items to the start of an array.
Array.shift(): Remove items from the start of an array.

That's all for today, see you next time.

Here is the link to the other articles on this Array series written by me:

Got any question, addition or correction? Please leave a comment.

Thank you for reading. 👍

Understanding JavaScript Array Series XIX - Array.shift()

Nedy Udombat — Wed, 23 Oct 2019 21:06:48 +0000

Yesterday, you asked a question saying That's cool and simple, but what if I want to remove the first element of an array?. Can't recall asking this? Check this article to refresh your memory.

Understanding JavaScript Array Series XVIII - Array.pop()

Nedy Udombat ・ Oct 22 '19

#javascript #webdev #beginners

So let's say we have this array [0, 1, 2, 3, 4, 5] and we want to remove the first element of the array what do we do?

Well, we can consult a magician or we can simply call the array.shift() method on the given array.

So you are saying that the Array.shift() method removes the first element of that array and returns the removed element? Yes, I am. Its syntax is similar to the Array.pop() syntax, all you have to do is append .shift() to the array you are working with like this:

const removedElem = arr.shift();

[arr]: This is the array in which whose first element you want to remove.

[elem]: This holds the element that is removed from the array.

Cool, it is kind of similar to array.pop(), except here it removes the element from the beginning of the array. Please, can you show us an example? Sure why not.

const numArray = [0, 1, 2, 3, 4, 5];
const elem = numArray.shift()

console.log(numArray) // [1, 2, 3, 4, 5];
console.log(elem) // 0

Just like the array.pop() method, no argument is required and the original array is mutated.

Let me guess if the array is empty this method returns undefined right? Yes, correct!

const emptyArray = [];
const elem = emptyArray.shift()

console.log(elem) // undefined

I am glad you are learning buddy. Do you have any questions for me?

Yes Yes, what if I want to put back the element I have removed either from the start of the array or the end of the array?

Good question. You can look into the Array.unshift() and the Array.push() method, we will talk about them tomorrow.

That's all for today, See you next time!!! 😆 😁

Thank you for reading. 👍

Understanding JavaScript Array Series XVIII - Array.pop()

Nedy Udombat — Tue, 22 Oct 2019 20:47:06 +0000

No, we are not popping champagne or anything like that. We want to remove the last item from an array. How do we accomplish this?

There is a Javascript array method called Array.pop(), This method removes the last element in an array and returns that element. It leaves you with a shorter array.

How do I write it?
Do you mean the syntax? If so then all you have to do is append the .pop() method to your array like this:

const elem = arr.pop()

[arr]: This is the array in which whose last element you want to remove.

[elem]: This holds the element that is removed from the array.

Can you use show us an example of how it is being used? Yea sure.

const numArray = [1, 2, 3, 4, 5];
const elem = numArray.pop()

console.log(numArray) // [1, 2, 3, 4];
console.log(elem) // 5

As you see above, all you have to do is call the method on the array, no arguments are required. The original array is mutated.

What if the array is empty, what happens then? Let's try it out

const emptyArray = [];
const elem = emptyArray.pop()

console.log(elem) // undefined

It returns undefined because there is no element in the array.

That's cool and simple, but what if I want to remove the first element of an array?
Well, you'll have to wait till tomorrow to find out, follow me here nedyudombat to get notified when I reveal the answer tomorrow. For now, just practise more on using the Array.pop() to remove elements from the end of an array.

That's all for today, See you next time!!! 😆 😁

Thank you for reading. 👍

Understanding JavaScript Array Series XVII - Array.concat()

Nedy Udombat — Mon, 21 Oct 2019 22:02:58 +0000

Concatenate literally means putting things together in a chain or series. So if we want to merge two arrays together, one way of doing it would be to concatenate it.

How do we concatenate two arrays?

We can achieve this by using the Array.concat() array method in javascript. This method merges two arrays into a new array. It takes array1 & array2 and merges them into array3.

Here is an example:

const array1 = [1, 2, 3, 4, 5];
const array2 = [6, 7, 8, 9];

const array3 = array1.concat(array2);
console.log(array3); // [1, 2, 3, 4, 5, 6, 7, 8, 9]

From the example, above we can see that this method creates a new array, passes in all the values of the first array, then it passes in the value of the second array.

Before we go into more examplesa let's look at the syntax

Thank you for reading. :thumbsup:
const newArray = array1.concat(value1, value2, ..., valueX)

[newArray]: This is the new array instance that is created as a result of the concatenation.

[array1]: This is the array which other arrays will be concatenated to.

[value1, value2, ..., valueX]: This is the value to be concatenated to array1. This value could also be other data types too like string, integer etc. If this value is not provided to the method, the method returns a shallow copy of array1.

N/B: For the primitive data types (string, integer, boolean ...), the array.concat() copies the value into the new array, but for some non-primitive data types (array, object ...), it copies the object reference into the newArray.

More Examples:

Can you merge two arrays?

const array1 = [1, 2, 3, 4, 5];
const array2 = ["a", "b", "c", "d"];

const array3 = array1.concat(array2);
console.log(array3); // [1, 2, 3, 4, 5, "a", "b", "c", "d"];

How about merging 3 arrays?

const array1 = [1, 2, 3, 4];
const array2 = ["a", "b", "c", "d"];
const array3 = [true, false, null, undefined];

const array4 = array1.concat(array2, array3);
console.log(array4); // [1, 2, 3, 4, "a", "b", "c", "d", true, false, null, undefined]

In this example, the concat() method merges the first array, then it merges the next one until there is has exhausted all the values provided.

What if we want to merge a string and a number into an array?

const array1 = [1, 2, 3, 4, 5];

const array2 = array1.concat("s", 4);
console.log(array2); // [1, 2, 3, 4, 5, "s", 4];

That's all for today, See you next time!!! 😆 😁

Here is the link to the other articles on this Array series written by me:

Got any question, addition or correction? Please leave a comment.

Thank you for reading. 👍

Understanding JavaScript Array Series XVI - Array.push()

Nedy Udombat — Fri, 18 Oct 2019 22:38:25 +0000

Let's assume you have a list of rappers like this J Cole, Kendrick Lamar, Chance The Rapper, Jay Z and you want to add one more rapper to that list, where would you add it? To the end of the list right? If you add Eminem to that list, you'll have J Cole, Kendrick Lamar, Chance The Rapper, Jay Z, Eminem.

We can achieve this behaviour using an array to store the names and an array method to add the new name to the list

const rappers = ['J cole', 'Kendrick Lamar', 'Chance The Rapper', 'Jay Z'];
const count = rappers.push('Eminem');
console.log(count) // 5
console.log(rappers); // ['J cole', 'Kendrick Lamar', 'Chance The Rapper', 'Jay Z', 'Eminem']

I was able to achieve this by using the Array.push() method. This method adds new items to the end of the array and returns the new length of the array. Just like in the example above, the result of rappers.push('Eminem') was returned into the count variable which logs 5.The rappers variable is also updated with the new item.

Let's take a look at the syntax:

arr.push(item1, item2, item3, ..., itemN);

[item1, item2, item3, ..., itemN]: These are the elements to be added to the array.

What happens When no new item is provided and the .push method is called on an array?

const rappers = ['J cole', 'Kendrick Lamar', 'Chance The Rapper', 'Jay Z'];
const count = rappers.push();
console.log(count); // 4
console.log(rappers); // ['J cole', 'Kendrick Lamar', 'Chance The Rapper', 'Jay Z']

In this scenario, nothing happens and the original length of the array is returned.

That's all for today, See you next week!!! 😆 😁

Here is the link to the other articles on this Array series written by me:

Got any question, addition or correction? Please leave a comment.

Thank you for reading. 👍

Understanding JavaScript Array Series XV - Array Loops & Iteration Part XII

Nedy Udombat — Thu, 17 Oct 2019 21:28:19 +0000

In the last two articles, I talked about iterating over arrays using the Array.indexOf() and the Array.lastIndexOf() array method. You can check it out below:

Understanding JavaScript Array Series XIII - Array Loops & Iteration Part X

Nedy Udombat ・ Oct 15 '19 ・ 3 min read

#javascript #webdev #beginners

Understanding JavaScript Array Series XIV - Array Loops & Iteration Part XI

Nedy Udombat ・ Oct 16 '19 ・ 3 min read

#javascript #webdev #beginners

The Array.indexOf() and the Array.lastIndexOf() both return the index when the element being searched for exists in the array and the -1 if it doesn't. What if we want it to return a boolean? 🤔 That returns true when the element we are searching for exists and false when it doesn't? Well you are in luck, today we will discuss the Array.includes() method.

Array.includes()

This method checks for a particular element in an array, if the element is found it returns true else it returns false.

It's syntax is similar to that of the Array.indexOf(), save for some differences:

// syntax
arr.includes(element, startIndex);

[element]: This is the element that will searched for in the array.

[startIndex]: This is the position(index) of the array to begin the search from. If this value is not supplied it defaults to 0. If the provided index is negative starts the search from arr.length + (startIndex).

Some Examples:

const names = ['soji', 'nedy', 'naza', 'chukwudi', 'lii', 'nedy'];

console.log(names.includes('nedy')) // true
console.log(names.includes('nedy', 6)) // false

What happens if the startIndex is equal to or greater than the length of the array?

const names = ['soji', 'nedy', 'naza', 'chukwudi', 'lii', 'nedy'];

console.log(names.includes('nedy', 6)) // false
console.log(names.includes('nedy', 30)) // false

In this scenario the array is not searched.

What happens if the calculated startIndex is less than 0?

const names = ['soji', 'nedy', 'naza', 'chukwudi', 'lii', 'nedy'];

console.log(names.includes('nedy', -30)) // true
console.log(names.includes('nedy', -8)) // false

In the first scenario, the calculated startIndex will be 6 + (-30) which is -24 it returns true, but in the second scenario where the calculated index is 6 + (-8) which is -2 it returns true. This is because for Array.includes() if the calculated startIndex is less than or equal to -1 * arr.length(which is -6 in this case), the entire array will be searched. In this situation, the first scenario -24 is less than -6 so the array will be searched, but in the second scenario -2 is greater than -6, hence, the array will not be searched.

What happens if Nedy or neDy is being searched for?

const names = ['soji', 'nedy', 'naza', 'chukwudi', 'lii', 'nedy'];

console.log(names.includes('Nedy',)) // false
console.log(names.includes('neDy', 3)) // false

The reason is simple Array.includes() is case sensitive.

Conclusion

Array.includes() should be used when you want to check if an element is present in an array. If you want to check for the position of the element in an array you can use Array.indexOf(), I wrote about it here

That's all for today, tomorrow we will talk about another set of functions used in array Iteration.

Here is the link to the other articles on this Array series written by me:

Got any question, addition or correction? Please leave a comment.

Thank you for reading. 👍

Understanding JavaScript Array Series XIV - Array Loops & Iteration Part XI

Nedy Udombat — Wed, 16 Oct 2019 22:09:50 +0000

In the previous article, I talked about iterating over arrays using the Array.indexOf() array method. You can check it out below:

Understanding JavaScript Array Series XIII - Array Loops & Iteration Part X

Nedy Udombat ・ Oct 15 '19 ・ 3 min read

#javascript #webdev #beginners

Do you recall this question from the article above?

What if we want to find the last position of nedy in this array ['soji', 'nedy', 'naza', 'chukwudi', 'lii', 'nedy']? What do we do 🤔?

Let's attempt to solve this yeah?

const names = ['soji', 'nedy', 'naza', 'chukwudi', 'lii', 'nedy'];
console.log(names.indexOf('nedy')) // 1
console.log(names.lastIndexOf('nedy')) // 5

From the solution above we can see that using Array.lastIndexOf() method actually gives us the desired answer.
So today, I will be talking about using Array.lastIndexOf() to iterate over arrays.

Array.lastIndexOf()

This method searches the array for the last position(index) of a specified element, if this element does not exist it returns -1. This is more like the opposite of the Array.indexOf(), because it searches for the last index while Array.indexOf() searches for the first index. Array.lastIndexOf() starts its search from the right(end) of the array to the left of the array, for Array.indexOf(), the reverse is the case.

It's syntax is similar to that of the Array.indexOf(), save for some differences:

// syntax
arr.lastIndexOf(element, startIndex);

[element]: This is the element that will searched for in the array.

[startIndex]: This is the position(index) of the array to begin the search from. If this value is not supplied it defaults to arr.length - 1. This index reduces by one every iteration, which means that the array is searched from right to left.

What happens if the startIndex is equal to or greater than the length of the array?

const names = ['soji', 'nedy', 'naza', 'chukwudi', 'lii', 'nedy'];

console.log(names.lastIndexOf('nedy', 8)) // 5
console.log(names.lastIndexOf('nedy', 6)) // 5

In this scenario the whole array will be searched.

What happens when we pass a negative value as the startIndex?

const names = ['soji', 'nedy', 'naza', 'chukwudi', 'lii', 'nedy'];

console.log(names.lastIndexOf('nedy', -6)) // -1
console.log(names.lastIndexOf('nedy', -4)) // 1

Just like in Array.indexOf(), when negative startIndex is passed, the method begins it search from arr.length + (startIndex), but here it searches from the index backwards. In the first instance, the search begins at (6+ (-6)) which is 0. At point we have the item soji and searching backwards we no longer have nedy so it returns -1. In the second scenario, the search begins at (6 + (-4)) which is 2. At that point the search begins at naza backwards, here we can find nedy at index 1.

Conclusion

Array.lastIndexOf() should be used when you get the last occurrence of a particular item in an array.

That's all for today, tomorrow we will talk about another set of functions used in array Iteration.

Here is the link to the other articles on this Array series written by me:

Got any question, addition or correction? Please leave a comment.

Thank you for reading. 👍

Understanding JavaScript Array Series XIII - Array Loops & Iteration Part X

Nedy Udombat — Tue, 15 Oct 2019 21:04:34 +0000

In the previous article, I talked about iterating over arrays using the Array.findIndex() array method. You can check it out below:

Understanding Javascript Array Series XII - Array Loops & Iteration Part IX

Nedy Udombat ・ Oct 14 '19 ・ 3 min read

#javascript #webdev #beginners

Today, I will talk about using Array.indexOf() to iterate over arrays.

Array.indexOf()

This method searches the array for a specified element and returns the position, if this element does not exist it returns -1. Let's assume your class teachers asks you to go into the class and look for a certain student called Naza. You go into the class as see Naza sitting by right corner of the class close to the window, and you go ahead to tell your teacher the position in which she is sitting. This is exactly the same way array.indexOf() behaves. It searches for the element in the array and returns the position in which it found that element.

// syntax
arr.indexOf(element, startIndex);

[element]: This is the element that will searched for in the array.

[startIndex]: This is the position(index) of the array to begin the search from. If this value is not supplied it defaults to 0.

Let's take a look at some instances where we find the indexOf nedy in this array ['soji', 'nedy', 'naza', 'chukwudi', 'lii']:

const names = ['soji', 'nedy', 'naza', 'chukwudi', 'lii'];
console.log(names.indexOf('nedy')) // 1

In this scenario the startIndex is not provided so it defaults to zero and the search starts from the beginning of the array

What if we provide a start value that is not 0?

const names = ['soji', 'nedy', 'naza', 'chukwudi', 'lii'];
console.log(names.indexOf('nedy', 2)) // -1
console.log(names.indexOf('naza', 2)) // 2

At position(index) 2 of the array we have naza, when we begin searching the array for nedy at that point we will not find it hence it returns -1. When we begin searching for Naza at that point it is the first item there so it returns the appropriate index.

What if the startIndex is equal to or greater than the length of the array?

const names = ['soji', 'nedy', 'naza', 'chukwudi', 'lii'];

console.log(names.indexOf('nedy', 7)) // -1
console.log(names.indexOf('nedy', 5)) // -1

The method returns -1 because the array will not be searched.

What happens when we pass a negative value as the startIndex?

const names = ['soji', 'nedy', 'naza', 'chukwudi', 'lii'];

console.log(names.indexOf('nedy', -2)) // -1
console.log(names.indexOf('nedy', -4)) // 1

Weird right? When the negative startIndex is passed as argument, the array begins it search from arr.length + (startIndex). In this case the search begins at 5 + (-2) which is equal to 3. Index 3 is chukwudi and at this point nedy can no longer be found in the array.
In the second case the search will start from 5 + (-4) which is equal to 1. At this point we can find nedy at index 1 so the index is returned.

What if we want to find the last position of nedy in this array ['soji', 'nedy', 'naza', 'chukwudi', 'lii', 'nedy']? What do we do 🤔?
Do you know the answer? please do well to tell us in the comment section and share some code snippet of how it can be achieved.

Follow me here @nedyudombat to get the solution to that question in the next part of my series publishing tomorrow.

Here is the link to the other articles on this Array series written by me:

Understanding Javascript Array Series XII - Array Loops & Iteration Part IX

Nedy Udombat — Mon, 14 Oct 2019 17:46:43 +0000

In the previous article, I talked about iterating over arrays using the Array.find() array method. You can check it out below:

Understanding Javascript Array Series XI - Array Loops & Iteration Part VIII

Nedy Udombat ・ Oct 11 '19 ・ 3 min read

#javascript #webdev #beginners

Today, I will talk about using array.findIndex() to iterate over arrays.

Array.findIndex()

This method is similar to the Array.find() in the last article. It is used to find the first element in an array that meets a particular criterion and returns its position(index) in the array.

The difference between Array.find() and Array.findIndex() is that the former returns the first item in the array that meets a specified criterion while the latter returns the postion(index) of that element in the given array.

// syntax
arr.findIndex(callback([currentValue], [arrayIndex], [arr]));

[currentValue]: This is the current item in the array that is being processed. After the procession, the current value becomes the value of the next element in the array.

[arrayIndex]: This is the index of the current value in the array. This also changes after the current value has been processed.

[arr]: This is the array being iterated over.

[callback]: This is basically a function to be performed on each element of the array. It accepts the first three items (currentValue, index, and array) as arguments.

Let's take a look at the examples from yesterday:

Find the first even number the given array [1, 3, 5, 6, 7, 8, 9] and its position:

// index     0  1  2  3  4  5  6 
const arr = [1, 3, 5, 6, 7, 8, 9];

// Array.find returns the element
const even = arr.find(num => num%2 === 0);
console.log(even); //6

// Array.findIndex returns the elements position in the array.
const evenIndex = arr.findIndex(num => num%2 === 0);
console.log(evenIndex); //3

Find the position of the first person in this array that is old enough to buy a car(18):

  // array
  const playerArr = [
    { name: "Soji", age: 8},
    { name: "Naza", age: 15},
    { name: "Nedy", age: 22},
    { name: "Ezekiel", age: 17},
    { name: "LII", age: 50},
  ]

  const firstEligibleCandidate = playerArr.findIndex(player => player.age > 18);
  console.log(firstEligibleCandidate); //2

Conclusion

Array.findIndex() is great when you want to get the position of the first element of an array that meets a particular criterion. In a situation where you want to get the element itself, we can use the Array.find() method. I wrote about it here.

Got any other instances for the use of the Array.findIndex() function? Please do well to share it in the comment section.

That's all for today, tomorrow we will talk about another set of functions used in array Iteration.

Here is the link to the other articles on this Array series written by me:

Got any question, addition or correction? Please leave a comment.

Thank you for reading. 👍