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# Python program to select Random value form list of lists

• Last Updated : 05 Sep, 2020

Given a list of lists. The task is to extract a random element from it.

Examples:

```Input : test_list = [[4, 5, 5], [2, 7, 4], [8, 6, 3]]
Output : 7
Explanation : Random number extracted from Matrix.

Input : test_list = [[4, 5, 5], [2, 7, 4], [8, 6, 3]], r_no = 2
Output : 6
Explanation : Random number extracted from 2nd row from Matrix.```

Method #1 : Using chain.from_iterable() + random.choice()

In this, we flatten the Matrix to list using from_iterable() and choice() is used to get a random number from the list.

## Python3

 `# Python3 code to demonstrate working of``# Random Matrix Element``# Using chain.from_iterables() + random.choice()``from` `itertools ``import` `chain``import` `random`` ` `# initializing list``test_list ``=` `[[``4``, ``5``, ``5``], [``2``, ``7``, ``4``], [``8``, ``6``, ``3``]]`` ` `# printing original list``print``(``"The original list is : "` `+` `str``(test_list))`` ` `# choice() for random number, from_iterables for flattening``res ``=` `random.choice(``list``(chain.from_iterable(test_list)))`` ` `# printing result``print``(``"Random number from Matrix : "` `+` `str``(res))`
Output

```The original list is : [[4, 5, 5], [2, 7, 4], [8, 6, 3]]
Random number from Matrix : 6
```

Method #2 : Using choice() to get element from particular row

If a row is mentioned, the choice() method can be used to get random element from that row.

## Python3

 `# Python3 code to demonstrate working of``# Random Matrix Element``# Using random.choice() [if row number given]``import` `random`` ` `# initializing list``test_list ``=` `[[``4``, ``5``, ``5``], [``2``, ``7``, ``4``], [``8``, ``6``, ``3``]]`` ` `# printing original list``print``(``"The original list is : "` `+` `str``(test_list))`` ` `# initializing Row number``r_no ``=` `1`` ` `# choice() for random number, from_iterables for flattening``res ``=` `random.choice(test_list[r_no])`` ` `# printing result``print``(``"Random number from Matrix Row : "` `+` `str``(res))`
Output
```The original list is : [[4, 5, 5], [2, 7, 4], [8, 6, 3]]
Random number from Matrix Row : 7
```

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