python3: TypeError: 'generator' object is not subscriptable

Question

I am very new to python. I am trying to run a simple code with a 2d list. But I'm getting an error: "TypeError: 'generator' object is not subscriptable". Can anyone please help me with how to solve this? Or what is wrong with the code.

import sys
import numpy as np
from scipy import stats

max_event = 1000000
a_bin = 10  # number each bin from 0-->10 where cumulant calculation will be done

# Define 2D array for [ bin, here 0->10][proton in each bin]
pArray = (() for nn in range(a_bin))
neve = (0 for mm in range(a_bin))

for ii in range(0, max_event):

    _a = np.random.randint(10)
    _b = np.random.randint(120)

    if ii % 1000 == 0:
        print(ii, _a, _b)

    for j in range(0, 10):
        if _a == j:
            pArray[j].append(_b)
            neve[j] += 1


print("filling done!")

for k in range(0, a_bin):

    mu2 = stats.mstats.moment(pArray[k], moment=2)
    mu4 = stats.mstats.moment(pArray[k], moment=4)

    print('serial = %d, mu_2 = %f , mu_4 = %f, event = %d' %
          (k, mu2, mu4, neve[k]))
    # print k, neve[k], c1[k], c2[k], c3[k], c4[k], c5[k], c6[k]

print("calculation done!")

Here is the output I am getting:

0 9 18 Traceback (most recent call last): File "calcumuBin.py", line 23, in pArray[j].append(_b) TypeError: 'generator' object is not subscriptable

Answer 1

You can change the pArray to be a list of lists that will prevent you from getting the TypeError: 'generator' object is not subscriptable

pArray = [[] for nn in range(a_bin)]
neve = [0 for mm in range(a_bin)]