Python: How does string.replace("\n", " ") behave in- and outside a function? -

the aim of code put string datastr two-dimensional list matrix. works in code_v1 when put same code function datastr = datastr.replace("\n", " ") doesn't replace \n same way did in code_v1 (form 1 " " several " "´s; compare output_v1 output_v2).

why case , how can fix it?

i read through numerous other questions regarding .replace(old, new) wrote string.replace(old, new) instead of string = string.replace(old, new).

thank in advance answers.

p.s. don't want use matrix math. why use two-dimensional list , not numpy.matrix.

p.p.s. first questions. if 1 has suggestion how improve readability of question or kind of improvements coding, please tell me.

code_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 \n string print(datastr)  datalist = datastr.split(" ")  # split string new element " " list datalist  matrix = [[1 y in range(20)] x in range(20)]  # create 20x20 "matrix"  print(datalist)  y in range(20):  # write data "matrix" integer     x in range(20):         matrix[x][y] = int(datalist[y * 20 + x]) 

output_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 exit code 0 

code_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 \n string     print(datastr)      datalist = datastr.split(" ")  # split string new element " " list datalist      matrix = [[1 y in range(20)] x in range(20)]  # create 20x20 "matrix"      matrix_data = [[1 y in range(20)] x in range(20)]      print(datalist)      y in range(20):  # write data "matrix" integer         x in range(20):             matrix[x][y] = int(datalist[y * 20 + x])   create_matrix() 

output_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 int() 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 exit code 1 

you indented lines of datastr. spaces @ start of each line significant:

    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. 

as result each line (except first), starts 4 spaces. \n newlines replaced fine, spaces still in place.

split string str.split() no arguments , won't need replace newlines spaces either:

datalist = datastr.split() 

str.split() no arguments (or none first argument) splits on arbitrary width whitespace, including newlines. doesn't matter if there 1 or multiple whitespace characters in-between.