# Get unflattened filtered Multidimensional Array in Javascript

I am able to filter the elements of matrix W to elements that satisfy the conditional statement `=>` keep elements in each inner matrix that is below the median value. The elements of the median array are the median values for each inner array.

```const W = [[45, 60, 15, 35],[45, 55, 75],[12, 34, 80, 65, 90]
];
const median = [ 40, 55, 65 ];
const Wmin = [];
for (let j = 0; j < W.length; j++) {
for (let k = 0; k < W[j].length; k++) {
if (W[j][k] < median[j]) {
Wmin.push(W[j][k]);
}
}
}

console.log(Wmin)```

I used a for-loop, but the resulting Wmin array is flattened. My goal is to be able to filter W and still get unflattened 2D array.

I am getting `Wmin = [ 15, 35, 45, 12, 34 ]`, but the expected array should be `Wmin = [ [15, 35], , [12, 34] ]`

You can use map and filter

```const W = [[45, 60, 15, 35],[45, 55, 75],[12, 34, 80, 65, 90]];
const median = [ 40, 55, 65 ];

const op = W.map(( inp, index) => inp.filter(e => e < median[index]))

console.log(op)```

Why my code is not working

You’re pushing values directly into array inside inner for loop, you need to create a temporary array and push value in it in inner loop and push the temporary to `Wmin` in outer loop

```const W = [[45, 60, 15, 35],[45, 55, 75],[12, 34, 80, 65, 90]];
const median = [ 40, 55, 65 ];
const Wmin = [];
for (let j = 0; j < W.length; j++) {
let temp = []
for (let k = 0; k < W[j].length; k++) {
if (W[j][k] < median[j]) {
temp.push(W[j][k]);
}
}
Wmin.push(temp)
}

console.log(Wmin)```