Python program to change the sign of elements of tuples in a list

Method 1:

One method to perform the sign conversion is by simply traversing the list using a loop and then for each tuple converting the sign of elements using the abs() function that returns the absolute value of the passed value. For negative, we will make the absolute value negative by multiplying it by (-1).

Program:

# Python program to change sign of element in a list 

tupList = [(-1, 4), (3, 1), (7, -6), (-4, -7)]
print("Initial tuple list : " + str(tupList))

signedTupList = []
for vals in tupList:
	signedTupList.append((abs(vals[0]), -1*abs(vals[1])))

print("Updated Tuple list : " + str(signedTupList))

Output:

Initial tuple list : [(-1, 4), (3, 1), (7, -6), (-4, -7)]
Updated Tuple list : [(1, -4), (3, -1), (7, -6), (4, -7)]

Method 2:

The code we used in method 1 can be converted to a single line of code using list comprehension in Python.

Program:

# Python program to change sign of element in a list 

tupList = [(-1, 4), (3, 1), (7, -6), (-4, -7)]
print("Initial tuple list : " + str(tupList))

signedTupList = [(abs(val[0]), -1*abs(val[1])) for val in tupList]

print("Updated Tuple list : " + str(signedTupList))

Output:

Initial tuple list : [(-1, 4), (3, 1), (7, -6), (-4, -7)]
Updated Tuple list : [(1, -4), (3, -1), (7, -6), (4, -7)]