Lỗi Loại: đối tượng 'NoneType' là unsubscriptable

Question

tôi có một chương trình python mà tạo ra một lỗi:

def update_ranges(phonemelist) : 
    """ updating the rows and columns of the list of input phonemes""" 
    # make a copy of the list as we're going to modify it (optional) 
    phonlist = phonemelist[:] 
    # we don't need the row titles, they just complicate things 
    rowtitles, phonlist = zip(*phonlist) 
    rows = len(phonlist) 
    columns = range(len(phonlist[0])) 

    # for each row except the last 
    for i in xrange(rows - 1): 
     # update it by going down all the rows below it 
     for k in xrange(i+1, rows): 
      # for both columns 
      for j in columns: 
       update(phonlist, i, j, k, j) 

    # put the row titles back in (optional) 
    phonlist = zip(rowtitles, phonlist) 
    return phonlist 

def update(phonlist, curr_row, curr_col, next_row, next_col) : 
    """ applying co-articulation rules for comparing the ranges """ 
    curr_low, curr_high = phonlist[curr_row][curr_col] 
    next_low, next_high = phonlist[next_row][next_col] 

    # Rule 1: when one of the ranges is (-1,-1) 
    # replace the current range if it's (-1, -1) as its empty 
    if (curr_low, curr_high) == (-1, -1) : 
     phonlist[curr_row][curr_col] = next_low, next_high 
     return 
    # do nothing if the next range is (-1,-1) 
    if (next_low, next_high) == (-1, -1) : 
     return 

    # Rule 2: when ranges don't overlap 
    # replace the lowest value of current range when the next range is lower than the current range 
    elif curr_low > next_high : 
     phonlist[curr_row][curr_col] = curr_low, curr_low 
     return 
    # replace the highest values of current range when the next range is higher than the current range 
    elif next_low > curr_high : 
     phonlist[curr_row][curr_col] = curr_high, curr_high 
     return 

    # Rule 3: when ranges completely overlap 
    elif curr_low <= next_low and next_high <= curr_high or curr_low >= next_low and next_high >= curr_high : 
     # replace the values of the next range when the next range completely lies in the current range 
     if curr_high - curr_low > next_high - next_low : 
      phonlist[curr_row][curr_col] = next_low, next_high 
      return 
     # replace the values of the current range when the current range completely lies in the next range 
     else : 
      phonlist[curr_row][curr_col] = curr_low, curr_high 
      return 

    # Rule 4: when the ranges partially overlap 
    else : 
     # replace the values that is common to both ranges when next range is further ahead of the current 
     if curr_low < next_low and curr_high < next_high : 
      phonlist[curr_row][curr_col] = next_low, curr_high 
      return 
     # replace the values that is common to both ranges when current range is further ahead of the next 
     else : 
      phonlist[curr_row][curr_col] = curr_low, next_high 
      return 

Lỗi:

File "coarticulation.py", line 217, in update 
    next_low, next_high = phonlist[next_row][next_col] 
TypeError: 'NoneType' object is unsubscriptable 

không lỗi có nghĩa là gì và làm thế nào để sửa chữa nó?

Answer 1

Nó không phải là một vấn đề với phần mã này. Nó có nghĩa là một trong hai

phonlist 

hoặc

phonlist[next_row] 

không phải là một list (hoặc một loại subscritable), một None. Tìm kiếm nơi bạn tạo danh sách.

Edit:

curr_low, curr_high = phonlist[curr_row][curr_col] 
next_low, next_high = phonlist[next_row][next_col] 

Bởi vì lỗi là ở dòng thứ hai, tôi nghĩ phonlist[next_row] là None.

Answer 2

Đây là lỗi mà Python trả về khi bạn cố gắng truy cập vào một giá trị subscripted (lập chỉ mục) từ giá trị None (Python của null tương đương):

>>> a = None 
>>> a[0] 
Traceback (most recent call last): 
    File "<stdin>", line 1, in <module> 
TypeError: 'NoneType' object is not subscriptable