Sort a sublist of elements in a list leaving the rest in place

Question

Say I have a sorted list of strings as in:

[\'A\', \'B\' , \'B1\', \'B11\', \'B2\', \'B21\', \'B22\', \'C\', \'C1\', \'C11\', \'C2\']

Now I wan

Answer 1

If I'm understanding your question clear, you are trying to sort an array by two attributes; the alphabet and the trailing 'number'.

You could just do something like

data = ['A', 'B' , 'B1', 'B11', 'B2', 'B21', 'B22', 'C', 'C1', 'C11', 'C2']
data.sort(key=lambda elem: (elem[0], int(elem[1:]))

but since this would throw an exception for elements without a number trailing them, we can go ahead and just make a function (we shouldn't be using lambda anyways!)

def sortKey(elem):
     try:
             attribute = (elem[0], int(elem[1:]))
     except:
             attribute = (elem[0], 0)

     return attribute

With this sorting key function made, we can sort the element in place by

data.sort(key=sortKey)

Also, you could just go ahead and adjust the sortKey function to give priority to certain alphabets if you wanted to.