如何使用python将某些csv文件列复制到另一个csv文件中？

Question

I have a 10 columns csv file and i would like to copy the first, the third and the seventh or another set of columns into a new csv file. Can you help me? I have this code but i can't transform it to have my need.

<code>
def selection( fr=sys.stdin, fw=sys.stdout, delim=';'):
    my_reader = csv.reader(fr, delimiter=delim)
    my_writer = csv.writer(fw, delimiter=delim)
    to_write = [ col for col in zip(*my_reader) if col[0] == 'Nb_doc' ]
    my_writer.writerows(zip(*to_write))
    return
</code>

this code copy only the column named 'nb_doc'.

Answer 1

Maybe you could have a list of field names you'd like to select from and check if the first element of the column is in there:

fields = ["Nb_doc", "SomeOtherField1", "SomeOtherField2"]

Then, your list comprehension probably just needs to look like this:

to_write = [ col for col in zip(*my_reader) if col[0] in fields ]

Answer 2

The following will copy just the first, third, and seventh columns:

colNums = [0, 2, 6]
to_write = [ col for i, col in enumerate(zip(*my_reader)) if i in colNums ]