Question

182

Filling up a 2D array with random numbers in javascript

rated 0 times [ 188] [ 6] / answers: 1 / hits: 15402 / 10 Years ago, mon, july 28, 2014, 12:00:00

I'm really sorry if anything like this has been posted here before but I couldn't find anything, I'm kinda new to the site still!

So for a while now I've been learning a bit about game development through html5 and javascript and I stumbled upon making tileset maps, I now have a tileset and an 2D array that I want to put certain tiles in (the number varies between 6 and 10 in this case).
I figured it could be a cool function to make the map choose between a small set of similar tiles so I don't have to specifically number every tile in the array(just define the type)

The method I have currently is probably the best for being able to define types but I want something that looks a bit cleaner and/or information to why my cleaner version dosen't work.

var ground = [

    [tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile()],

    [tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile()],

    [tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile()],

    [tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile()],

    [tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile()],

    [tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile()],

    [tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile()],

    [tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile()],

    [tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile(),tile()]];



function tile() {

    var y = (Math.random() * 5 | 0) + 6;

    return y;

}

This is the code I've been using so far, I have to edit every element of the code with the tile() function to get a random number in each one, what I wanted to have was something like this:

for (var i = 0 ; i < 15; i++) {

    for (var j = 0; j < 9; j++) {

        ground[[i],[j]] = (Math.random() * 5 | 0) + 6;

    }

}

to fill the array without having to add the function to each spot.

I have a feeling that I'm missing a return function or something along those lines but honestly I have no idea.

Answers

Only authorized users can answer the question. Please sign in first, or register a free account.

natalyah

Add To Favorites

Follow

Total Points: 371

Total Questions: 90

Total Answers: 105

Location: The Bahamas

Member since Wed, Apr 12, 2023

1 Year ago

answered 10 Years ago citlalia · Accepted Answer

You were thinking in the right direction but there are some errors in your code ;)

You have to initialize the array first before you can push elements into it.

And you were counting i++ twice

Javascript

var ground = []; // Initialize array

for (var i = 0 ; i < 15; i++) {

    ground[i] = []; // Initialize inner array

    for (var j = 0; j < 9; j++) { // i++ needs to be j++

        ground[i][j] = (Math.random() * 5 | 0) + 6;

    }

}

Maybe even better (reusable)

function createGround(width, height){

    var result = [];

    for (var i = 0 ; i < width; i++) {

        result[i] = [];

        for (var j = 0; j < height; j++) {

            result[i][j] = (Math.random() * 5 | 0) + 6;

        }

    }

    return result;

}

// Create a new ground with width = 15 & height = 9

var ground = createGround(15, 9);