How to get Median string value from array with multiple strings in Python?

I have array, which holds values like for example 1's and 0's. like this:

['00100','00101','00101','01100','01001','00101']

And I want to get median of each char in each string of array:

return would be something like this:

'00101'

If you can give example in Python it would be great.

Solution

Python has natural idioms for this sort of problem. The idea is to split things into nice digestible chunks of all the 0-th chars, all the 1-th chars, all the 2-th chars, ... etc. (the zip(*a) part); then figure out the median for each chunk (the sorted(d)[len(a)/2] part); and then to join those chunks back together again. That gives us the one-liner:

def findMedians(a):
    return ''.join(sorted(d)[len(a)/2] for d in zip(*a))

print findMedians(['00100','00101','00101','01100','01001','00101'])
# 00101
print findMedians(['1210', '2501', '1234'])
# 1211

If you find this a bit confusing, try:

print zip('123','456','789')
a = ['123','456','789']
print zip(*a)

to see what the '*' operator is doing here.