Merge multiple 2d lists considering axis in order
My purpose is to combine multiple 2d list in order such as: a = [[1,2],[3,1]] b= [[3,6],[2,9]] c = [[5,1],[8,10]] Expected: [[1,2,3,6,5,1],[3,1,2,9,8,10]] Following other's advice from this site, I tried to use collections module like the code below: from collections import Counter a = [[1,2],[3,1]] b= [[3,6],[2,9]] c = [[5,1],[8,10]] d = [[k,v] for k,v in (Counter(dict(a)) + Counter(dict(b))+ Counter(dict(c))).items()] print d However, the result is [[1, 2], [3, 1], [3, 6], [2, 9]] which is not what I expected. Do you have any idea to solve this problem? Maybe if there is function or module