Bakhtiyor - 9 months ago 50

Javascript Question

For instance I have a matrix like this:

`|1 2 3|`

|4 5 6|

|7 8 9|

and I need it to convert into a matrix like this:

`|1 4 7|`

|2 5 8|

|3 6 9|

What is the best and optimal way to achieve this goal?

Answer Source

see http://www.shamasis.net/2010/02/transpose-an-array-in-javascript-and-jquery

```
transpose = function(a) {
// Calculate the width and height of the Array
var w = a.length ? a.length : 0,
h = a[0] instanceof Array ? a[0].length : 0;
// In case it is a zero matrix, no transpose routine needed.
if(h === 0 || w === 0) { return []; }
/**
* @var {Number} i Counter
* @var {Number} j Counter
* @var {Array} t Transposed data is stored in this array.
*/
var i, j, t = [];
// Loop through every item in the outer array (height)
for(i=0; i<h; i++) {
// Insert a new row (array)
t[i] = [];
// Loop through every item per item in outer array (width)
for(j=0; j<w; j++) {
// Save transposed data.
t[i][j] = a[j][i];
}
}
return t;
};
```

transpose([[1,2,3],[4,5,6],[7,8,9]]);