Given a dual Tuple list, the task is to write a python program to convert second element to negative magnitude of each tuple and first element to positive magnitude of each tuple.

Input :test_list = [(3, -1), (-4, -3), (1, 3), (-2, 5), (-4, 2), (-9, -3)]

Output :[(3, -1), (4, -3), (1, -3), (2, -5), (4, -2), (9, -3)]

Explanation :All the first elements are positive, and 2nd index elements are negative, as desired.

Input: test_list = [(3, -1), (-4, -3), (1, 3), (-2, 5)]

Output :[(3, -1), (4, -3), (1, -3), (2, -5)]

Explanation :All the first elements are positive, and 2nd index elements are negative, as desired.

**Method 1 : ***Using **loop** and** abs()*

In this, we iterate using loop and initially convert both to positive magnitude using abs(). The 2nd element is signed “-” and is converted to negative element as desired.

**Example:**

## Python3

`# initializing lists` `test_list ` `=` `[(` `3` `, ` `-` `1` `), (` `-` `4` `, ` `-` `3` `), (` `1` `, ` `3` `), (` `-` `2` `, ` `5` `), (` `-` `4` `, ` `2` `), (` `-` `9` `, ` `-` `3` `)]` ` ` `# printing original list` `print` `(` `"The original list is : "` `+` `str` `(test_list))` ` ` `res ` `=` `[]` `for` `sub ` `in` `test_list:` ` ` ` ` `# 2nd element converted to negative magnitude` ` ` `res.append((` `abs` `(sub[` `0` `]), ` `-` `abs` `(sub[` `1` `])))` ` ` `# printing result` `print` `(` `"Updated Tuple list : "` `+` `str` `(res))` |

**Output:**

The original list is : [(3, -1), (-4, -3), (1, 3), (-2, 5), (-4, 2), (-9, -3)]

Updated Tuple list : [(3, -1), (4, -3), (1, -3), (2, -5), (4, -2), (9, -3)]

**Method 2 : ***Using** list comprehension** *

Similar to above method, only difference being list comprehension is used as one liner to perform this task.

**Example:**

## Python3

`# initializing lists` `test_list ` `=` `[(` `3` `, ` `-` `1` `), (` `-` `4` `, ` `-` `3` `), (` `1` `, ` `3` `), (` `-` `2` `, ` `5` `), (` `-` `4` `, ` `2` `), (` `-` `9` `, ` `-` `3` `)]` ` ` `# printing original list` `print` `(` `"The original list is : "` `+` `str` `(test_list))` ` ` `# list comprehension used as one liner` `res ` `=` `[(` `abs` `(sub[` `0` `]), ` `-` `abs` `(sub[` `1` `])) ` `for` `sub ` `in` `test_list]` ` ` `# printing result` `print` `(` `"Updated Tuple list : "` `+` `str` `(res))` |

**Output:**

The original list is : [(3, -1), (-4, -3), (1, 3), (-2, 5), (-4, 2), (-9, -3)]

Updated Tuple list : [(3, -1), (4, -3), (1, -3), (2, -5), (4, -2), (9, -3)]

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