Sometimes we need to find the unique values in a list, that is comparatively easy and its summation and has been discussed earlier. But we can also get a matrix as input i.e a list of lists, finding unique in them are discussed in this article. Let’s see certain ways in which this can be achieved.

**Method #1 : Using set() + list comprehension + sum()**

The set function can be used to convert the individual list to a non-repeating element list and the list comprehension is used to iterate to each of the lists. The task of performing summation is performed using sum().

`# Python3 code to demonstrate ` `# Non-Repeating value Summation in Matrix ` `# set() + list comprehension + sum() ` ` ` `# initializing matrix ` `test_matrix ` `=` `[[` `1` `, ` `3` `, ` `1` `], [` `4` `, ` `5` `, ` `3` `], [` `1` `, ` `2` `, ` `4` `]] ` ` ` `# printing the original matrix ` `print` `(` `"The original matrix is : "` `+` `str` `(test_matrix)) ` ` ` `# using set() + list comprehension + sum() ` `# Non-Repeating value Summation in Matrix ` `res ` `=` `sum` `(` `list` `(` `set` `(i ` `for` `j ` `in` `test_matrix ` `for` `i ` `in` `j))) ` ` ` `# printing result ` `print` `(` `"Unique values summation in matrix are : "` `+` `str` `(res)) ` |

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**Output :**

The original matrix is : [[1, 3, 1], [4, 5, 3], [1, 2, 4]] Unique values summation in matrix are : 15

**Method #2 : Using chain() + set() + sum()**

The chain function performs the similar task that a list comprehension performs but in a faster way as it uses iterators for its internal processing and hence faster. The task of performing summation is performed using sum().

`# Python3 code to demonstrate ` `# Non-Repeating value Summation in Matrix ` `# chain() + set() + sum() ` `from` `itertools ` `import` `chain ` ` ` `# initializing matrix ` `test_matrix ` `=` `[[` `1` `, ` `3` `, ` `1` `], [` `4` `, ` `5` `, ` `3` `], [` `1` `, ` `2` `, ` `4` `]] ` ` ` `# printing the original matrix ` `print` `(` `"The original matrix is : "` `+` `str` `(test_matrix)) ` ` ` `# using chain() + set() + sum() ` `# Non-Repeating value Summation in Matrix ` `res ` `=` `sum` `(` `list` `(` `set` `(chain(` `*` `test_matrix)))) ` ` ` `# printing result ` `print` `(` `"Unique values summation in matrix are : "` `+` `str` `(res)) ` |

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**Output :**

The original matrix is : [[1, 3, 1], [4, 5, 3], [1, 2, 4]] Unique values summation in matrix are : 15

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