List of lists write to file without brackets and commas-CodePudding

I have a list of lists e.g. testlist = [[1, 2, 4, 5, 6, 7, 8, 9, 10], [11, 12, 13, 14, 15, 16, 17, 18, 19, 20] that I want to write them to file but replace commas with space and more specifically with a tab separator, \t which adds a big space between characters, so the final result inside the file would look like this:

1   2   3   4   5   6   7   8   9   10 #first list
11  12  13  14  15  16  17  18  19  20 #second list
...

I tried using replace() but I get error that I can't use it with int chars. I have tried

for x in testlist:
    x.replace(",", "\t")

CodePudding user response：

Hope this helps.

testlist = [[1, 2, 4, 5, 6, 7, 8, 9, 10], [11, 12, 13, 14, 15, 16, 17, 18, 19, 20]]

with open("output.txt", "w") as f:
    for aList in testlist:
        myString = (''.join('{:<5}\t'*len(aList))).format(*aList,)
        print(myString)
        f.write(myString)

Output

1       2       4       5       6       7       8       9       10      
11      12      13      14      15      16      17      18      19      20

CodePudding user response：

This can be achieved without the aid of additional module imports as follows:

testlist = [[1, 2, 4, 5, 6, 7, 8, 9, 10], [11, 12, 13, 14, 15, 16, 17, 18, 19, 20]]
with open('output.txt', 'w') as out_file:
    for e in testlist:
        print('\t'.join(map(str, e)), file=out_file)

CodePudding user response：

You can do it yourself, but he most pythonic way is to use csv library

here the example from official doc

import csv

with open('output.tsv', 'wt') as out_file:
    tsv = csv.writer(out_file, delimiter='\t')
    tsv.writerows(testlist)