# Python – Get Matrix Mean

• Last Updated : 18 Oct, 2022

Given a Matrix, Find its mean.

Input : test_list = [[5, 6, 7], [7, 5, 6]] Output : 6.0 Explanation : 36 / 6 = 6.0
Input : test_list = [[5, 6, 7, 4, 8]] Output : 6.0 Explanation : 30 / 5 = 6.0

Method #1 : Using list comprehension + sum() + len() + zip()

The combination of above functions can be used to solve this problem. In this, we perform the mean calculation using sum() and len(), zip() along with * operator does task of extracting each element of rows of matrix.

## Python3

 `# Python3 code to demonstrate working of``# Matrix Mean``# Using list comprehension + sum() + len() + zip()` `# initializing lists``test_list ``=` `[[``5``, ``6``, ``3``], [``8``, ``3``, ``1``], [``9``, ``10``, ``4``], [``8``, ``4``, ``2``]]` `# printing original list``print``(``"The original list : "` `+` `str``(test_list))` `# zip() to get all elements``# sum() / len() gives mean``# extracts column mean``res ``=` `[``sum``(idx) ``/` `len``(idx) ``for` `idx ``in` `zip``(``*``test_list)]` `# extracts all elements mean``res ``=` `sum``(res) ``/` `len``(res)``    ` `# printing result``print``(``"Matrix Mean : "` `+` `str``(res))`

Output

```The original list : [[5, 6, 3], [8, 3, 1], [9, 10, 4], [8, 4, 2]]
Matrix Mean : 5.25```

Method #2 : Using mean() + zip() + list comprehension

This is another method in which this task can be performed. In this, we extract mean using inbuilt method of mean() .

## Python3

 `# Python3 code to demonstrate working of``# Matrix Mean``# Using mean() + zip() + list comprehension``from` `statistics ``import` `mean` `# initializing lists``test_list ``=` `[[``5``, ``6``, ``3``], [``8``, ``3``, ``1``], [``9``, ``10``, ``4``], [``8``, ``4``, ``2``]]` `# printing original list``print``(``"The original list : "` `+` `str``(test_list))` `# zip() to get all elements``# mean() gives mean``# extracts column mean``res ``=` `[mean(idx) ``for` `idx ``in` `zip``(``*``test_list)]` `# extracts all elements mean``res ``=` `mean(res)``    ` `# printing result``print``(``"Matrix Mean : "` `+` `str``(res))`

Output

```The original list : [[5, 6, 3], [8, 3, 1], [9, 10, 4], [8, 4, 2]]
Matrix Mean : 5.25```

Method #3 : Using extend() and mean() method of statistics module

## Python3

 `# Python3 code to demonstrate working of``# Matrix Mean``import` `statistics``# initializing lists``test_list ``=` `[[``5``, ``6``, ``3``], [``8``, ``3``, ``1``], [``9``, ``10``, ``4``], [``8``, ``4``, ``2``]]` `# printing original list``print``(``"The original list : "` `+` `str``(test_list))``x``=``[]``for` `i ``in` `test_list:``    ``x.extend(i)``res``=``statistics.mean(x)``# printing result``print``(``"Matrix Mean : "` `+` `str``(res))`

Output

```The original list : [[5, 6, 3], [8, 3, 1], [9, 10, 4], [8, 4, 2]]
Matrix Mean : 5.25```

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