Python | Get positive elements from given list of lists

Given a list of list, the task is to get only positive element from given list. Below are some ways to solve the above problem.

**Method #1: Using Iteration**

`# Python code to get positive ` `# element from list of list` ` ` `# List Initialisation` `Input` `=` `[[` `10` `, ` `-` `11` `, ` `222` `], [` `42` `, ` `-` `222` `, ` `-` `412` `, ` `99` `, ` `-` `87` `]]` `Output ` `=` `[]` ` ` `# Using iteration` `for` `elem ` `in` `Input` `:` ` ` `temp ` `=` `[]` ` ` `for` `x ` `in` `elem:` ` ` `if` `x>` `0` `:` ` ` `temp.append(x)` ` ` `Output.append(temp)` ` ` `# printing output` `print` `(` `"Initial List is :"` `, ` `Input` `)` `print` `(` `"Modified list is :"` `, Output)` |

**Output:**

Initial List is : [[10, -11, 222], [42, -222, -412, 99, -87]] Modified list is : [[10, 222], [42, 99]]

**Method #2: Using map and list Comprehension**

`# Python code to get positive element ` `# from list of list` ` ` `# List Initialisation` `Input` `=` `[[` `10` `, ` `-` `11` `, ` `222` `], [` `42` `, ` `-` `222` `, ` `-` `412` `, ` `99` `, ` `-` `87` `]]` ` ` `# Using list comprehension and map` `temp ` `=` `map` `(` `lambda` `elem: ` `filter` `(` `lambda` `a: a>` `0` `, elem), ` `Input` `)` `Output ` `=` `[[a ` `for` `a ` `in` `elem ` `if` `a>` `0` `] ` `for` `elem ` `in` `temp]` ` ` `# printing output` `print` `(` `"Initial List is :"` `, ` `Input` `)` `print` `(` `"Modified list is :"` `, Output)` |

**Output:**

Initial List is : [[10, -11, 222], [42, -222, -412, 99, -87]] Modified list is : [[10, 222], [42, 99]]

**Method #3: Using List Comprehension**

`# Python code to get positive element ` `# from list of list` ` ` `# List Initialisation` `Input` `=` `[[` `10` `, ` `-` `11` `, ` `222` `], [` `42` `, ` `-` `222` `, ` `-` `412` `, ` `99` `, ` `-` `87` `]]` ` ` `# Using list comprehension` `Output ` `=` `[ [b ` `for` `b ` `in` `a ` `if` `b>` `0` `] ` `for` `a ` `in` `Input` `]` ` ` `# printing output` `print` `(` `"Initial List is :"` `, ` `Input` `)` `print` `(` `"Modified list is :"` `, Output)` |

**Output:**

Initial List is : [[10, -11, 222], [42, -222, -412, 99, -87]] Modified list is : [[10, 222], [42, 99]]

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