1D array to 2D array in Javascript

Question

So in my javascript I have a huge 1D array and I want to convert it into a 2D array. This is what I have so far, but doesn't seem to work.

 var arrLines = strRawContents.split(",");
 var array2;
 for (int i = 0; i < 98; i++) {
 for (int j = 0; j < 5; j++) {
 array2[i][j] = arrLines[(j * 98) + i];
 }
 }
 return arrLines
 }

This is what I currently have, where I'm trying to make 98 rows and in each row, there is 5 columns. My goal is complicated. If my 1D array were to be [1,2,3,4,5,6,7,8,9,10 and so on], My 2D array at [0][0] should be 1, at [0][1] should be 2 and so on until [0][7] would be 8, then [1][0] would be 9, [1][1] would be 10 and so forth.

• MaxxyPoo: Oh It's suppose to be returning array2 o.o. So yah ignore that/
• Fahmi: There's no 2D or associated array in javascript as we have in PHP etc. Instead you use object. Just update line 2 to var array2 = {};

Answer 1

In every outer loop, create an array. In the inner loop, push contents into it, at the end of the outer loop, push that newly created array into the final 2-d array.

var arrLines = strRawContents.split(",");
var array2 = [];
for (var i = 0; i < 98; i++) {
 var arr = [];
 for (var j = 0; j < 5; j++) {
 arr.push(arrLines[(i * 5) + j]);
 }
 array2.push(arr);
}
return arr2;

Some mistakes in your original code:

1. You need to initialize your array2 to be an empty array.
2. There's no int keyword in JavaScript. Use var or let (let is preferred but not all browsers support it yet.
3. The formula should be (i * 5) + j not (j * 98) + i.
4. The return value should be array2.

• MaxxyPoo: Thank you, this is very useful. But for the 2D variable I have, I want the first array for example, (0) to be the row, then the next 6 items will be the column. And then it repeats with the 7th array being the next row and then 6 items after that being its column. Is there a way to do this, I would very appreciate the help!
• Yangshun Tay: I'm not understanding your comment here. Could you update your question to illustrate the intended result with an example?
• Yangshun Tay: Please state the starting value for strRawContents and how the final 2-d array should look like. Sorry your comments are not very clear.
• MaxxyPoo: So for example if my 1D array were to be [1,2,3,4,5,6,7,8,9,10 so on] My 2D array would be like so, [0][0] would be 1, [0][1] would be 2, so on till [0][7] would be 8. Then [1][0] would be 9, [1][1] would be 10. Hopefully this clears it up, just realized this seems very complicated.
• Yangshun Tay: I realized my answer does that currently, just that there are 98 rows of 5 elements each, which you specified in the question. Is it not working for you?