Python: Find the min, max value in a list of tuples

Question

alist = [(1,3),(2,5),(2,4),(7,5)] 

I need to get the min max value for each position in tuple.

Fox example: The exepected output of alist is

min_x = 1 max_x = 7  min_y = 3 max_y = 5 

Is there any easy way to do?

Answer 1

map(max, zip(*alist)) 

This first unzips your list, then finds the max for each tuple position

>>> alist = [(1,3),(2,5),(2,4),(7,5)] >>> zip(*alist) [(1, 2, 2, 7), (3, 5, 4, 5)] >>> map(max, zip(*alist)) [7, 5] >>> map(min, zip(*alist)) [1, 3] 

This will also work for tuples of any length in a list.

Answer 2

>>> from operator import itemgetter >>> alist = [(1,3),(2,5),(2,4),(7,5)] >>> min(alist)[0], max(alist)[0] (1, 7) >>> min(alist, key=itemgetter(1))[1], max(alist, key=itemgetter(1))[1] (3, 5)