# Python – Matrix Custom Multiplier

• Last Updated : 30 Dec, 2020

Sometimes, while working with data, we can have a problem in which we need to multiply each row of matrix with a different multiplier. This kind of application is important in data science domain. Lets discuss certain ways in which this task can be performed.

Method #1 : Using loop + `zip()`
The combination of above functions can be used to perform this task. In this, we iterate through each row and perform the task of multiplication using zip().

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 `# Python3 code to demonstrate ``# Matrix Custom Multiplier``# using loop + zip()`` ` `# Initializing list``test_list1 ``=` `[[``1``, ``3``], [``5``, ``6``], [``8``, ``9``]]``test_list2 ``=` `[``4``, ``3``, ``6``]`` ` `# printing original lists``print``(``"The original list 1 is : "` `+` `str``(test_list1))``print``(``"The original list 2 is : "` `+` `str``(test_list2))`` ` `# Matrix Custom Multiplier``# using loop + zip()``res ``=` `[]``for` `mul, sub ``in` `zip``(test_list2, test_list1):``    ``temp ``=` `[]``    ``for` `ele ``in` `sub:``        ``temp.append(mul ``*` `ele)``    ``res.append(temp)`` ` `# printing result ``print` `(``"Matrix after custom multiplication : "` `+` `str``(res))`
Output :

```The original list 1 is : [[1, 3], [5, 6], [8, 9]]
The original list 2 is : [4, 3, 6]
Matrix after custom multiplication : [[4, 12], [15, 18], [48, 54]]
```

Method #2 : Using list comprehension + `zip()`
The combination of above methods can be used to solve this problem. In this, we just iterate through the list and perform the task of multiplication in one liner.

 `# Python3 code to demonstrate ``# Matrix Custom Multiplier``# using list comprehension + zip()`` ` `# Initializing list``test_list1 ``=` `[[``1``, ``3``], [``5``, ``6``], [``8``, ``9``]]``test_list2 ``=` `[``4``, ``3``, ``6``]`` ` `# printing original lists``print``(``"The original list 1 is : "` `+` `str``(test_list1))``print``(``"The original list 2 is : "` `+` `str``(test_list2))`` ` `# Matrix Custom Multiplier``# using list comprehension + zip()``res ``=`  `[[mul ``*` `ele ``for` `ele ``in` `sub] ``for` `mul, sub ``in` `zip``(test_list2, test_list1)]`` ` `# printing result ``print` `(``"Matrix after custom multiplication : "` `+` `str``(res))`
Output :
```The original list 1 is : [[1, 3], [5, 6], [8, 9]]
The original list 2 is : [4, 3, 6]
Matrix after custom multiplication : [[4, 12], [15, 18], [48, 54]]
```

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