Question

I have a python dict as below

mymap={'java':40,'haskell':60,'ruby':50,'python':70,'scala':30,'lisp':80,'scheme':75}

I have the keys put in sublists

mapkeys = [['haskell','java'],['lisp','python'],['scala','scheme'],['ruby']]

Now,I need to create a list of lists of values of these keys as below

[[60,40],[80,70],[30,75],[50] ]

I tried using list comprehension ,but failed to yield any results

Answer 1

Try this:

>>> [[mymap[k] for k in l] for l in mapkeys]
[[60, 40], [80, 70], [30, 75], [50]]

For a non-nested list, remove the brackets and reverse the for statements:

>>> [mymap[k] for l in mapkeys for k in l]
[60, 40, 80, 70, 30, 75, 50]