python code for creating a list of numbers for every k element of a different list
for every k elements in a dataframe, I want to add a number to a list. for example, if k = 3 my list would be [0,0,0,1,1,1,2,2,2,3,3,3,…]
for every k elements in a dataframe, I want to add a number to a list. for example, if k = 3 my list would be [0,0,0,1,1,1,2,2,2,3,3,3,…]