Array in JavaScript is undefined

May 20, 2022

I am very new to JavaScript but have good experience with C and java. For whatever reason my code below will not fill in the array with values other than undefined. I’m trying to simply fill an array with a random set of numbers for a blackjack game

let randomSuite;
let randomNum
let count = 0;
var cards = new Array(56);
window.onload = function main(){
const suites = [
    "H",
    "D",
    "S",
    "C"
];

for(let i = 0 ; i < 56 ; i++){
    randomNum = (Math.random * 12) + 1;
    randomSuite = Math.random * 3;
    cards.push = randomNum;
    console.log(cards[i]);
    count++;
}
alert(cards[1]);
}
function hitFunc(){
    alert("works " + cards[0]);
}

*{
    margin: 0;
    padding : 0;
    font-family: sans-serif;
}

.main{
    width: 100%;
    height: 100vh;
    background-color:black;
}

.img1{
    position: relative;
    z-index: -1;
    margin: 10px auto 20px;
    display: block;
    width: 75%;
    height: 75%;
}

.img2{
    position: relative;
    z-index: 1;
    margin: 10px auto 20px;
    display: block;
    bottom: 200px;
    right: 400px;
    width: 7%;
    height: 7%;
}

.hitButton {
z-index: 1;
position: relative;
text-align: center;
left: 225px;
bottom: 550px;
}

.center {
    display: block;
    margin-left: auto;
    margin-right: auto;
    width: 50%;
    color: aliceblue;
    object-position: center;
  }

Here’s what I have. The alerts are used to show that the function is being completed. Any help is appreciated Please leave an explanation as well. This is my first post on stack overflow let me know if there’s anyway to improve the quality of my post.

>Solution :

Math.random is a function; use Math.random()
Same for push, use cards.push(randomNum)
You were defining an array with 56 spots new array(56) but since you’re using push you’ll need to create an empty array so you’re pussing to the desired index. Otherwise, instead of push, just set it on the index: cards[i] = randomNum
No need for the count variable since the loop iterator (i) has the same value

let randomSuite;
let randomNum
var cards = new Array();

window.onload = function main(){
    const suites = [
        "H",
        "D",
        "S",
        "C"
    ];

    for(let i = 0 ; i < 56 ; i++){
        randomNum = (Math.random() * 12) + 1;
        randomSuite = Math.random() * 3;
        cards.push(randomNum);
    }
    console.log(cards)
}

*{
    margin: 0;
    padding : 0;
    font-family: sans-serif;
}

.main{
    width: 100%;
    height: 100vh;
    background-color:black;
}

.img1{
    position: relative;
    z-index: -1;
    margin: 10px auto 20px;
    display: block;
    width: 75%;
    height: 75%;
}

.img2{
    position: relative;
    z-index: 1;
    margin: 10px auto 20px;
    display: block;
    bottom: 200px;
    right: 400px;
    width: 7%;
    height: 7%;
}

.hitButton {
z-index: 1;
position: relative;
text-align: center;
left: 225px;
bottom: 550px;
}

.center {
    display: block;
    margin-left: auto;
    margin-right: auto;
    width: 50%;
    color: aliceblue;
    object-position: center;
  }