How to sort an array by the nth column?
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# How to sort an array by the nth column?

This recipe helps you sort an array by the nth column

## Recipe Objective

While handling arrays, we might need to sort array on certain columns.

So this recipe is a short example on how to sort an array by the nth column. Let's get started.

## Step 1 - Import the library

``` import numpy as np ```

Let's pause and look at these imports. Numpy is generally helpful in data manipulation while working with arrays. It also helps in performing mathematical operation.

## Step 2 - Defining random array

``` a = np.array([[9, 2, 3],[4, 5, 6],[7, 0, 5]]) ```

We have created a random array.

## Step 3 - Sorting and printing array

``` a = a[a[:,1].argsort()] print(a) ```

We now use argsort feature to sort on any column. Here, we are sorting on 2nd column.

## Step 4 - Lets look at our dataset now

Once we run the above code snippet, we will see:

```Scroll down to the ipython file below to visualize the output.
```

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