Python:string.replace（"；\n"；，"；）在函数内外的行为如何？

我的代码的目的是将字符串

datastr

放入二维列表

矩阵

。这在Code_v1中非常有效，但当我将相同的代码放入函数时，datastr=datastr.replace（“\n”，“”）不会像在Code_v1中那样替换\n（将一个“替换为多个””；比较输出_v1和输出_v2）

为什么会这样？我该如何解决

我已经阅读了许多关于

.replace（旧，新）

的其他问题，但是他们都写了

string.replace（旧，新）

而不是

string=string.replace（旧，新）

提前感谢您的回答

另外，我不想在数学中使用矩阵。这就是为什么我使用二维列表而不是

numpy.matrix

这是我的第一个问题。如果有人对如何提高问题的可读性或对我的编码有任何改进，请告诉我

代码(v1):

datastr = """08 02 22 97 38 15 00 40 00 75 04 05 07 78 52 12 50 77 91 08
49 49 99 40 17 81 18 57 60 87 17 40 98 43 69 48 04 56 62 00
81 49 31 73 55 79 14 29 93 71 40 67 53 88 30 03 49 13 36 65
52 70 95 23 04 60 11 42 69 24 68 56 01 32 56 71 37 02 36 91
22 31 16 71 51 67 63 89 41 92 36 54 22 40 40 28 66 33 13 80
24 47 32 60 99 03 45 02 44 75 33 53 78 36 84 20 35 17 12 50
32 98 81 28 64 23 67 10 26 38 40 67 59 54 70 66 18 38 64 70
67 26 20 68 02 62 12 20 95 63 94 39 63 08 40 91 66 49 94 21
24 55 58 05 66 73 99 26 97 17 78 78 96 83 14 88 34 89 63 72
21 36 23 09 75 00 76 44 20 45 35 14 00 61 33 97 34 31 33 95
78 17 53 28 22 75 31 67 15 94 03 80 04 62 16 14 09 53 56 92
16 39 05 42 96 35 31 47 55 58 88 24 00 17 54 24 36 29 85 57
86 56 00 48 35 71 89 07 05 44 44 37 44 60 21 58 51 54 17 58
19 80 81 68 05 94 47 69 28 73 92 13 86 52 17 77 04 89 55 40
04 52 08 83 97 35 99 16 07 97 57 32 16 26 26 79 33 27 98 66
88 36 68 87 57 62 20 72 03 46 33 67 46 55 12 32 63 93 53 69
04 42 16 73 38 25 39 11 24 94 72 18 08 46 29 32 40 62 76 36
20 69 36 41 72 30 23 88 34 62 99 69 82 67 59 85 74 04 36 16
20 73 35 29 78 31 90 01 74 31 49 71 48 86 81 16 23 57 05 54
01 70 54 71 83 51 54 69 16 92 33 48 61 43 52 01 89 19 67 48"""

datastr = datastr.replace("\n", " ")  # Remove all \n from the string
print(datastr)

datalist = datastr.split(" ")  # Split the string into a new element by " " for the list datalist

matrix = [[1 for y in range(20)] for x in range(20)]  # create 20x20 "matrix"

print(datalist)

for y in range(20):  # Write data into the "matrix" as integer
    for x in range(20):
        matrix[x][y] = int(datalist[y * 20 + x])

输出_v1：

C:\Users\i7\AppData\Local\Programs\Python\Python35-32\pythonw.exe C:/Users/i7/Dropbox/Programmieren/Python/test.py
08 02 22 97 38 15 00 40 00 75 04 05 07 78 52 12 50 77 91 08 49 49 99 40 17 81 18 57 60 87 17 40 98 43 69 48 04 56 62 00 81 49 31 73 55 79 14 29 93 71 40 67 53 88 30 03 49 13 36 65 52 70 95 23 04 60 11 42 69 24 68 56 01 32 56 71 37 02 36 91 22 31 16 71 51 67 63 89 41 92 36 54 22 40 40 28 66 33 13 80 24 47 32 60 99 03 45 02 44 75 33 53 78 36 84 20 35 17 12 50 32 98 81 28 64 23 67 10 26 38 40 67 59 54 70 66 18 38 64 70 67 26 20 68 02 62 12 20 95 63 94 39 63 08 40 91 66 49 94 21 24 55 58 05 66 73 99 26 97 17 78 78 96 83 14 88 34 89 63 72 21 36 23 09 75 00 76 44 20 45 35 14 00 61 33 97 34 31 33 95 78 17 53 28 22 75 31 67 15 94 03 80 04 62 16 14 09 53 56 92 16 39 05 42 96 35 31 47 55 58 88 24 00 17 54 24 36 29 85 57 86 56 00 48 35 71 89 07 05 44 44 37 44 60 21 58 51 54 17 58 19 80 81 68 05 94 47 69 28 73 92 13 86 52 17 77 04 89 55 40 04 52 08 83 97 35 99 16 07 97 57 32 16 26 26 79 33 27 98 66 88 36 68 87 57 62 20 72 03 46 33 67 46 55 12 32 63 93 53 69 04 42 16 73 38 25 39 11 24 94 72 18 08 46 29 32 40 62 76 36 20 69 36 41 72 30 23 88 34 62 99 69 82 67 59 85 74 04 36 16 20 73 35 29 78 31 90 01 74 31 49 71 48 86 81 16 23 57 05 54 01 70 54 71 83 51 54 69 16 92 33 48 61 43 52 01 89 19 67 48
['08', '02', '22', '97', '38', '15', '00', '40', '00', '75', '04', '05', '07', '78', '52', '12', '50', '77', '91', '08', '49', '49', '99', '40', '17', '81', '18', '57', '60', '87', '17', '40', '98', '43', '69', '48', '04', '56', '62', '00', '81', '49', '31', '73', '55', '79', '14', '29', '93', '71', '40', '67', '53', '88', '30', '03', '49', '13', '36', '65', '52', '70', '95', '23', '04', '60', '11', '42', '69', '24', '68', '56', '01', '32', '56', '71', '37', '02', '36', '91', '22', '31', '16', '71', '51', '67', '63', '89', '41', '92', '36', '54', '22', '40', '40', '28', '66', '33', '13', '80', '24', '47', '32', '60', '99', '03', '45', '02', '44', '75', '33', '53', '78', '36', '84', '20', '35', '17', '12', '50', '32', '98', '81', '28', '64', '23', '67', '10', '26', '38', '40', '67', '59', '54', '70', '66', '18', '38', '64', '70', '67', '26', '20', '68', '02', '62', '12', '20', '95', '63', '94', '39', '63', '08', '40', '91', '66', '49', '94', '21', '24', '55', '58', '05', '66', '73', '99', '26', '97', '17', '78', '78', '96', '83', '14', '88', '34', '89', '63', '72', '21', '36', '23', '09', '75', '00', '76', '44', '20', '45', '35', '14', '00', '61', '33', '97', '34', '31', '33', '95', '78', '17', '53', '28', '22', '75', '31', '67', '15', '94', '03', '80', '04', '62', '16', '14', '09', '53', '56', '92', '16', '39', '05', '42', '96', '35', '31', '47', '55', '58', '88', '24', '00', '17', '54', '24', '36', '29', '85', '57', '86', '56', '00', '48', '35', '71', '89', '07', '05', '44', '44', '37', '44', '60', '21', '58', '51', '54', '17', '58', '19', '80', '81', '68', '05', '94', '47', '69', '28', '73', '92', '13', '86', '52', '17', '77', '04', '89', '55', '40', '04', '52', '08', '83', '97', '35', '99', '16', '07', '97', '57', '32', '16', '26', '26', '79', '33', '27', '98', '66', '88', '36', '68', '87', '57', '62', '20', '72', '03', '46', '33', '67', '46', '55', '12', '32', '63', '93', '53', '69', '04', '42', '16', '73', '38', '25', '39', '11', '24', '94', '72', '18', '08', '46', '29', '32', '40', '62', '76', '36', '20', '69', '36', '41', '72', '30', '23', '88', '34', '62', '99', '69', '82', '67', '59', '85', '74', '04', '36', '16', '20', '73', '35', '29', '78', '31', '90', '01', '74', '31', '49', '71', '48', '86', '81', '16', '23', '57', '05', '54', '01', '70', '54', '71', '83', '51', '54', '69', '16', '92', '33', '48', '61', '43', '52', '01', '89', '19', '67', '48']

Process finished with exit code 0

代码(v2):

#globals
matrix = 0
matrix_data = 0


def create_matrix():

    global matrix
    global matrix_data

    datastr = """08 02 22 97 38 15 00 40 00 75 04 05 07 78 52 12 50 77 91 08
    49 49 99 40 17 81 18 57 60 87 17 40 98 43 69 48 04 56 62 00
    81 49 31 73 55 79 14 29 93 71 40 67 53 88 30 03 49 13 36 65
    52 70 95 23 04 60 11 42 69 24 68 56 01 32 56 71 37 02 36 91
    22 31 16 71 51 67 63 89 41 92 36 54 22 40 40 28 66 33 13 80
    24 47 32 60 99 03 45 02 44 75 33 53 78 36 84 20 35 17 12 50
    32 98 81 28 64 23 67 10 26 38 40 67 59 54 70 66 18 38 64 70
    67 26 20 68 02 62 12 20 95 63 94 39 63 08 40 91 66 49 94 21
    24 55 58 05 66 73 99 26 97 17 78 78 96 83 14 88 34 89 63 72
    21 36 23 09 75 00 76 44 20 45 35 14 00 61 33 97 34 31 33 95
    78 17 53 28 22 75 31 67 15 94 03 80 04 62 16 14 09 53 56 92
    16 39 05 42 96 35 31 47 55 58 88 24 00 17 54 24 36 29 85 57
    86 56 00 48 35 71 89 07 05 44 44 37 44 60 21 58 51 54 17 58
    19 80 81 68 05 94 47 69 28 73 92 13 86 52 17 77 04 89 55 40
    04 52 08 83 97 35 99 16 07 97 57 32 16 26 26 79 33 27 98 66
    88 36 68 87 57 62 20 72 03 46 33 67 46 55 12 32 63 93 53 69
    04 42 16 73 38 25 39 11 24 94 72 18 08 46 29 32 40 62 76 36
    20 69 36 41 72 30 23 88 34 62 99 69 82 67 59 85 74 04 36 16
    20 73 35 29 78 31 90 01 74 31 49 71 48 86 81 16 23 57 05 54
    01 70 54 71 83 51 54 69 16 92 33 48 61 43 52 01 89 19 67 48"""

    datastr = datastr.replace("\n", " ")  # Remove all \n from the string
    print(datastr)

    datalist = datastr.split(" ")  # Split the string into a new element by " " for the list datalist

    matrix = [[1 for y in range(20)] for x in range(20)]  # create 20x20 "matrix"

    matrix_data = [[1 for y in range(20)] for x in range(20)]

    print(datalist)

    for y in range(20):  # Write data into the "matrix" as integer
        for x in range(20):
            matrix[x][y] = int(datalist[y * 20 + x])


create_matrix()

输出_v2：

C:\Users\i7\AppData\Local\Programs\Python\Python35-32\pythonw.exe C:/Users/i7/Dropbox/Programmieren/Python/test.py
Traceback (most recent call last):
08 02 22 97 38 15 00 40 00 75 04 05 07 78 52 12 50 77 91 08     49 49 99 40 17 81 18 57 60 87 17 40 98 43 69 48 04 56 62 00     81 49 31 73 55 79 14 29 93 71 40 67 53 88 30 03 49 13 36 65     52 70 95 23 04 60 11 42 69 24 68 56 01 32 56 71 37 02 36 91     22 31 16 71 51 67 63 89 41 92 36 54 22 40 40 28 66 33 13 80     24 47 32 60 99 03 45 02 44 75 33 53 78 36 84 20 35 17 12 50     32 98 81 28 64 23 67 10 26 38 40 67 59 54 70 66 18 38 64 70     67 26 20 68 02 62 12 20 95 63 94 39 63 08 40 91 66 49 94 21     24 55 58 05 66 73 99 26 97 17 78 78 96 83 14 88 34 89 63 72     21 36 23 09 75 00 76 44 20 45 35 14 00 61 33 97 34 31 33 95     78 17 53 28 22 75 31 67 15 94 03 80 04 62 16 14 09 53 56 92     16 39 05 42 96 35 31 47 55 58 88 24 00 17 54 24 36 29 85 57     86 56 00 48 35 71 89 07 05 44 44 37 44 60 21 58 51 54 17 58     19 80 81 68 05 94 47 69 28 73 92 13 86 52 17 77 04 89 55 40     04 52 08 83 97 35 99 16 07 97 57 32 16 26 26 79 33 27 98 66     88 36 68 87 57 62 20 72 03 46 33 67 46 55 12 32 63 93 53 69     04 42 16 73 38 25 39 11 24 94 72 18 08 46 29 32 40 62 76 36     20 69 36 41 72 30 23 88 34 62 99 69 82 67 59 85 74 04 36 16     20 73 35 29 78 31 90 01 74 31 49 71 48 86 81 16 23 57 05 54     01 70 54 71 83 51 54 69 16 92 33 48 61 43 52 01 89 19 67 48
  File "C:/Users/i7/Dropbox/Programmieren/Python/test.py", line 51, in <module>
    create_matrix()
  File "C:/Users/i7/Dropbox/Programmieren/Python/test.py", line 46, in create_matrix
matrix[x][y] = int(datalist[y * 20 + x])
ValueError: invalid literal for int() with base 10: ''
['08', '02', '22', '97', '38', '15', '00', '40', '00', '75', '04', '05', '07', '78', '52', '12', '50', '77', '91', '08', '', '', '', '', '49', '49', '99', '40', '17', '81', '18', '57', '60', '87', '17', '40', '98', '43', '69', '48', '04', '56', '62', '00', '', '', '', '', '81', '49', '31', '73', '55', '79', '14', '29', '93', '71', '40', '67', '53', '88', '30', '03', '49', '13', '36', '65', '', '', '', '', '52', '70', '95', '23', '04', '60', '11', '42', '69', '24', '68', '56', '01', '32', '56', '71', '37', '02', '36', '91', '', '', '', '', '22', '31', '16', '71', '51', '67', '63', '89', '41', '92', '36', '54', '22', '40', '40', '28', '66', '33', '13', '80', '', '', '', '', '24', '47', '32', '60', '99', '03', '45', '02', '44', '75', '33', '53', '78', '36', '84', '20', '35', '17', '12', '50', '', '', '', '', '32', '98', '81', '28', '64', '23', '67', '10', '26', '38', '40', '67', '59', '54', '70', '66', '18', '38', '64', '70', '', '', '', '', '67', '26', '20', '68', '02', '62', '12', '20', '95', '63', '94', '39', '63', '08', '40', '91', '66', '49', '94', '21', '', '', '', '', '24', '55', '58', '05', '66', '73', '99', '26', '97', '17', '78', '78', '96', '83', '14', '88', '34', '89', '63', '72', '', '', '', '', '21', '36', '23', '09', '75', '00', '76', '44', '20', '45', '35', '14', '00', '61', '33', '97', '34', '31', '33', '95', '', '', '', '', '78', '17', '53', '28', '22', '75', '31', '67', '15', '94', '03', '80', '04', '62', '16', '14', '09', '53', '56', '92', '', '', '', '', '16', '39', '05', '42', '96', '35', '31', '47', '55', '58', '88', '24', '00', '17', '54', '24', '36', '29', '85', '57', '', '', '', '', '86', '56', '00', '48', '35', '71', '89', '07', '05', '44', '44', '37', '44', '60', '21', '58', '51', '54', '17', '58', '', '', '', '', '19', '80', '81', '68', '05', '94', '47', '69', '28', '73', '92', '13', '86', '52', '17', '77', '04', '89', '55', '40', '', '', '', '', '04', '52', '08', '83', '97', '35', '99', '16', '07', '97', '57', '32', '16', '26', '26', '79', '33', '27', '98', '66', '', '', '', '', '88', '36', '68', '87', '57', '62', '20', '72', '03', '46', '33', '67', '46', '55', '12', '32', '63', '93', '53', '69', '', '', '', '', '04', '42', '16', '73', '38', '25', '39', '11', '24', '94', '72', '18', '08', '46', '29', '32', '40', '62', '76', '36', '', '', '', '', '20', '69', '36', '41', '72', '30', '23', '88', '34', '62', '99', '69', '82', '67', '59', '85', '74', '04', '36', '16', '', '', '', '', '20', '73', '35', '29', '78', '31', '90', '01', '74', '31', '49', '71', '48', '86', '81', '16', '23', '57', '05', '54', '', '', '', '', '01', '70', '54', '71', '83', '51', '54', '69', '16', '92', '33', '48', '61', '43', '52', '01', '89', '19', '67', '48']

Process finished with exit code 1

C:\Users\i7\AppData\Local\Programs\Python\Python35-32\pythonw.exe C:/Users/i7/Dropbox/Programmieren/Python/test.py
回溯（最近一次呼叫最后一次）：
08 02 22 97 38 15 00 40 00 75 04 05 07 78 52 12 50 77 91 08     49 49 99 40 17 81 18 57 60 87 17 40 98 43 69 48 04 56 62 00     81 49 31 73 55 79 14 29 93 71 40 67 53 88 30 03 49 13 36 65     52 70 95 23 04 60 11 42 69 24 68 56 01 32 56 71 37 02 36 91     22 31 16 71 51 67 63 89 41 92 36 54 22 40 40 28 66 33 13 80     24 47 32 60 99 03 45 02 44 75 33 53 78 36 84 20 35 17 12 50     32 98 81 28 64 23 67 10 26 38 40 67 59 54 70 66 18 38 64 70     67 26 20 68 02 62 12 20 95 63 94 39 63 08 40 91 66 49 94 21     24 55 58 05 66 73 99 26 97 17 78 78 96 83 14 88 34 89 63 72     21 36 23 09 75 00 76 44 20 45 35 14 00 61 33 97 34 31 33 95     78 17 53 28 22 75 31 67 15 94 03 80 04 62 16 14 09 53 56 92     16 39 05 42 96 35 31 47 55 58 88 24 00 17 54 24 36 29 85 57     86 56 00 48 35 71 89 07 05 44 44 37 44 60 21 58 51 54 17 58     19 80 81 68 05 94 47 69 28 73 92 13 86 52 17 77 04 89 55 40     04 52 08 83 97 35 99 16 07 97 57 32 16 26 26 79 33 27 98 66     88 36 68 87 57 62 20 72 03 46 33 67 46 55 12 32 63 93 53 69     04 42 16 73 38 25 39 11 24 94 72 18 08 46 29 32 40 62 76 36     20 69 36 41 72 30 23 88 34 62 99 69 82 67 59 85 74 04 36 16     20 73 35 29 78 31 90 01 74 31 49 71 48 86 81 16 23 57 05 54     01 70 54 71 83 51 54 69 16 92 33 48 61 43 52 01 89 19 67 48
文件“C:/Users/i7/Dropbox/Programmieren/Python/test.py”，第51行，在
创建矩阵（）
文件“C:/Users/i7/Dropbox/Programmieren/Python/test.py”，第46行，在创建矩阵中
矩阵[x][y]=int（数据列表[y*20+x]）
ValueError:基数为10的int（）的文本无效：“”
['08', '02', '22', '97', '38', '15', '00', '40', '00', '75', '04', '05', '07', '78', '52', '12', '50', '77', '91', '08', '', '', '', '', '49', '49', '99', '40', '17', '81', '18', '57', '60', '87', '17', '40', '98', '43', '69', '48', '04', '56', '62', '00', '', '', '', '', '81', '49', '31', '73', '55', '79', '14', '29', '93', '71', '40', '67', '53', '88', '30', '03', '49', '13', '36', '65', '', '', '', '', '52', '70', '95', '23', '04', '60', '11', '42', '69', '24', '68', '56', '01', '32', '56', '71', '37', '02', '36', '91', '', '', '', '', '22', '31', '16', '71', '51', '67', '63', '89', '41', '92', '36', '54', '22', '40', '40', '28', '66', '33', '13', '80', '', '', '', '', '24', '47', '32', '60', '99', '03', '45', '02', '44', '75', '33', '53', '78', '36', '84', '20', '35', '17', '12', '50', '', '', '', '', '32', '98', '81', '28', '64', '23', '67', '10', '26', '38', '40', '67', '59', '54', '70', '66', '18', '38', '64', '70', '', '', '', '', '67', '26', '20', '68', '02', '62', '12', '20', '95', '63', '94', '39', '63', '08', '40', '91', '66', '49', '94', '21', '', '', '', '', '24', '55', '58', '05', '66', '73', '99', '26', '97', '17', '78', '78', '96', '83', '14', '88', '34', '89', '63', '72', '', '', '', '', '21', '36', '23', '09', '75', '00', '76', '44', '20', '45', '35', '14', '00', '61', '33', '97', '34', '31', '33', '95', '', '', '', '', '78', '17', '53', '28', '22', '75', '31', '67', '15', '94', '03', '80', '04', '62', '16', '14', '09', '53', '56', '92', '', '', '', '', '16', '39', '05', '42', '96', '35', '31', '47', '55', '58', '88', '24', '00', '17', '54', '24', '36', '29', '85', '57', '', '', '', '', '86', '56', '00', '48', '35', '71', '89', '07', '05', '44', '44', '37', '44', '60', '21', '58', '51', '54', '17', '58', '', '', '', '', '19', '80', '81', '68', '05', '94', '47', '69', '28', '73', '92', '13', '86', '52', '17', '77', '04', '89', '55', '40', '', '', '', '', '04', '52', '08', '83', '97', '35', '99', '16', '07', '97', '57', '32', '16', '26', '26', '79', '33', '27', '98', '66', '', '', '', '', '88', '36', '68', '87', '57', '62', '20', '72', '03', '46', '33', '67', '46', '55', '12', '32', '63', '93', '53', '69', '', '', '', '', '04', '42', '16', '73', '38', '25', '39', '11', '24', '94', '72', '18', '08', '46', '29', '32', '40', '62', '76', '36', '', '', '', '', '20', '69', '36', '41', '72', '30', '23', '88', '34', '62', '99', '69', '82', '67', '59', '85', '74', '04', '36', '16', '', '', '', '', '20', '73', '35', '29', '78', '31', '90', '01', '74', '31', '49', '71', '48', '86', '81', '16', '23', '57', '05', '54', '', '', '', '', '01', '70', '54', '71', '83', '51', '54', '69', '16', '92', '33', '48', '61', '43', '52', '01', '89', '19', '67', '48']
进程已完成，退出代码为1

您缩进了

datastr

的行。每行开头的空格都很重要：

因此，每行（第一行除外）都以4个额外的空格开始。您的

\n

换行符被很好地替换了，但是那些多余的空格仍然存在

使用

str.Split（）

    datastr = """08 02 22 97 38 15 00 40 00 75 04 05 07 78 52 12 50 77 91 08
    49 49 99 40 17 81 18 57 60 87 17 40 98 43 69 48 04 56 62 00
    81 49 31 73 55 79 14 29 93 71 40 67 53 88 30 03 49 13 36 65 ... """
# ^^ spaces here.

datalist = datastr.split()