sorting list of coordinates in python

Question

how can I sort the list below based on the b component instead of the a component if I use the sorted()method in Python

list = [(a1,b1),(a2,b2),(a3,b3)]

Answer 1

You can use the sort-key to set a specific function to decide the sorting criterion. In this case it might be enough to just pick the second value for each entry, i.e. x[1]. See here for more information on the sort and sorting functions.

sorted_list = sorted(unsorted_list, key=lambda x: x[1])

and, for example, if you notice that you want to sort in descending and not ascending order:

sorted_list = sorted(unsorted_list, key=lambda x: -x[1])