What's the best way to get the index of an elemnt inside of a 2d array?

Question

So I'm working on a project where I have a two dimensional array, and I need to find the location of an element placed on the second dimension, without knowing the index of it's first dimension.

I know that I can possibly iterate over the parts, checking to see if list[x].index(y) isn't a value error, but that makes my code a lot less elegant looking, and I wanted to know if there's a better way to do it, like a 2d .index method?

Answer 1

Assuming you don't want to reinvent the wheel I believe this question has the answer you're looking for: Is there a Numpy function to return the first index of something in an array?

import numpy as np
a = np.array([[1,2,4],[4,5,6]])
item = 4
row_indices, col_indices = np.where(a == item)

Answer 2

If length of all rows are equal, you can use this code:

index_2d = [item for row in list for item in row].index(y)
index_row = index_2d / ROW_LENGTH
index_col = index_2d % ROW_LENGTH

Answer 3

Try something like this.

>>> l = [[1,2,3],[4,5],[6,7,8,9]]
>>> x = 1
>>> y = 2
>>> v = l[x][y] if len(l) > x and len(l[x]) > y else None
>>> v is None
True