Problem with recursive multidimensional matrix

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Problem with recursive multidimensional matrix

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#1 by (2 votes)
#2 by (2 votes)
#3 by (2 votes)

4

I need to make a recursive multidimensional array in javascript. I have made a function that clones an array, and I thought what the function of the matrix would be, but I do not know what I'm doing wrong.

I want, for example, matrix([2,3,4]) to return this to me:

[[[0,1,2,3]], [0,1,2,3], [0,1,2,3]], [[0,1,2,3], [0, 1,2,3], [0,1,2,3]]]

This means that the length of the array entered is the number of dimensions, and the numbers are the value of the dimensions, having a 3D matrix of 2x3x4 (height, width and height).

This is my code:

function copiarArray(A)
{
    var B=[]
    for(var i=0;i<A.length;i++)
    {
        B[i]=A[i]
    }
    return B
}
function matriz(dims)
{
    var I=dims[0]
    dims.shift()
    var A=[]
    A.length=I
    for(var i=0;i<I;i++)
    {
        var dims2=copiarArray(dims)
        A[i]=matriz(dims)
        dims=dims2
    }
    return A
}

Currently the error he gives me is:

Uncaught RangeError: Invalid array length (...)

Edit:

If possible, I would like matriz(dims) to only receive one argument, that is, not allow more than one ... Otherwise, instead of [0,1,2,3] , let all values be in 0 , in this way, [0,0,0,0] .

javascript matrices

asked by ArtEze 23.11.2016 в 02:43

source

3 answers

2

//x = alto, y = ancho, z = profundidad. Visto desde el 3D :D
function matriz(x, y, z){
    var array = [];
    var i = 0;
    for(var xi = 0; xi <= x-1; xi++){
        array.push(new Array());
        for(var yi = 0; yi <= y-1; yi++){
            array[xi].push(new Array());
            for(var zi = 0; zi <= z-1; zi++){
                array[xi][yi].push(new Array());
                array[xi][yi][zi] = i;
                i++;
            }
            i = 0;
        }
    }
    return array;
}

console.log(matriz(2, 2, 2));

I hope it works for you and that you understand: D

answered by 23.11.2016 в 03:26

2

As you ask for recursive, I think you mean this:

function matrix(dims) {  
  if (dims.length === 0) return 0;  
  var res = [],
      dimension = dims[0];
  for (var i = 0; i < dimension; i++) {
    res[i] = matrix(dims.slice(1)) || res.length;
  }
  return res;
}

var res = matrix([2, 3, 4]);
document.getElementById('res').innerText = JSON.stringify(res);

I leave you here a jsfiddle: link

answered by 23.11.2016 в 10:09

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score 2 · Accepted Answer

In addition to the response from @jcarrenog , you could also do so:

Array(length) , to create a array of the indicated length.
.shift() , to remove the first element of array .
dims.length ? , to know if you still have to execute the recursive function.
dims.slice(0) , to clone the array that is passed to the function.

Example:

function matrix(dims) {  
  var arr = Array(dims.shift() || 0);
  for (var idx = 0; idx < arr.length; idx++) {
    arr[idx] = dims.length ? matrix(dims.slice(0)) : idx;
  }
  return arr;
}

console.log(JSON.stringify(matrix([])));
console.log(JSON.stringify(matrix([2])));
console.log(JSON.stringify(matrix([2,3])));
console.log(JSON.stringify(matrix([2,3,4])));