Subtract the mean of each row of a matrix?
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# Subtract the mean of each row of a matrix?

Subtract the mean of each row of a matrix

## Recipe Objective

While handling arrays, we might feel a need to subtract each element of row from its mean.

So this recipe is a short example on how to subtract the mean of each row of a matrix. 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.random.rand(3, 4) print(a) ```

We have created a random array of size 3x4.

## Step 3 - Subtracting mean

``` b = a - a.mean(axis=1, keepdims=True) print(b) ```

First, we find mean across each row and then subtract it from the original array. Finally, we are printing down the new array.

## 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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