How do I delete the Nth list item from a list of lists (column delete)?

python list slice del
P Moran picture P Moran · Nov 6, 2012 · Viewed 27.5k times · Source

How do I delete a "column" from a list of lists?
Given:

L = [
     ["a","b","C","d"],
     [ 1,  2,  3,  4 ],
     ["w","x","y","z"]
    ]

I would like to delete "column" 2 to get:

L = [
     ["a","b","d"],
     [ 1,  2,  4 ],
     ["w","x","z"]
    ]

Is there a slice or del method that will do that? Something like:

del L[:][2]

Answer

Dietrich Epp picture Dietrich Epp · Nov 6, 2012

You could loop.

for x in L:
    del x[2]

If you're dealing with a lot of data, you can use a library that support sophisticated slicing like that. However, a simple list of lists doesn't slice.

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