Pandas python what to solve in IndexError

Question

I receive the following error when I try to count occurences of each element in ListA from ListB .

 ListA = [*range(0,10000000, 1)] ListB = [5,4,778,577,369,1147, 7851387,115547,...] count_arr = np.bincount(ListB) Number_of_counts = [count_arr[x] for x in ListA]

I get the following error with which I do not know what is wrong since ListA is just a range of numbers.

 IndexError Traceback (most recent call last) <ipython-input-18-2f121c135a65> in <module> 1 count_arr = np.bincount(ListA) ----> 2 Number_of_counts = [count_arr[x] for x in ListB] <ipython-input-18-2f121c135a65> in <listcomp>(.0) 1 count_arr = np.bincount(ListB) ----> 2 Number_of_counts = [count_arr[x] for x in ListA] IndexError: index 1715766 is out of bounds for axis 0 with size 1715766

Answer 1

ListA's length is bigger than count_arr 's length. Therefore, when you loop through count_arr using ListA 's indexes, you get and error. Their length should be the same