Hi Bohyun:

I found the CSV module in Python to be surprisingly confusing when I
first encountered it, given Python's elegance in many other cases. The
Dialect thing drove me nuts at first!

Lots of other people have answered in bits and pieces in this thread,
including non-Python approaches, but here's what works for me (with
the single example row that you've provided):

import csv
with open('noid_refworks.txt','rU') as csvinput:
    with open('withid.txt', 'w') as csvoutput:
        csvinput.seek(0)
        reader = csv.reader(csvinput, 'excel-tab')
        writer = csv.writer(csvoutput, 'excel-tab', quoting=csv.QUOTE_NONE)
        for row in reader:
            row.insert(0, '')
            writer.writerow(row)

The two changes that I've made were:

1. Remove the dialect sniffer and provide one explicitly ('excel-tab',
which uses a tab-delimited format); with the single line example, my
sniffer kept thinking the dialect was comma-delimited, which was
_very_ confusing to me :)
2. row.insert(0, '') before writing the row to prepend an empty
element at the start of the list, instead of building a new list with
an explicit tab (which would end up having to be escaped, which might
be why it shows up as an L in your output)

This snippet works in both Python 2.7.5 and Python 3.3.3 for me.

Hope this helps,
Dan


On Mon, Nov 25, 2013 at 12:10 PM, Bohyun Kim <[log in to unmask]> wrote:
> Hi all,
>
> I am new to Python and was wondering if I can get some help with my short script. What I would like the script to do is:
> (1) Read the tab delimited file generated by Refworks
> (2) Output exactly the same file but the blank column added in front.
> (This is for prepping the exported tab delimited file from refworks so that it can be imported into MySQL; so any suggestions in the line of timtoady would be also appreciated.)
>
> This is what I have so far. It works, but then in the output file, I end up getting some weird character in each line in the second column (first column in the original input file). I also don't really get what escapechar=' ' does or what I am supposed to put in there.
>
> import csv
> with open('noid_refworks.txt','rU') as csvinput:
>     with open('withid.txt', 'w') as csvoutput:
>         dialect = csv.Sniffer().sniff(csvinput.read(1024))
>         csvinput.seek(0)
>         reader = csv.reader(csvinput, dialect)
>         writer = csv.writer(csvoutput, dialect, escapechar='\'', quoting=csv.QUOTE_NONE)
>         for row in reader:
>             writer.writerow(['\t']+row)
>
> A row in the original file is like this (Tab delimited and no quotations, some fields have commas and quotation marks inside.):
>
> Reference Type    Authors, Primary    Title Primary    Periodical Full    Periodical Abbrev    Pub Year    Pub Date Free From    Volume    Issue    Start Page    Other Pages    Keywords    Abstract    Notes    Personal Notes    Authors, Secondary    Title Secondary    Edition    Publisher    Place Of Publication    Authors, Tertiary    Authors, Quaternary    Authors, Quinary    Title, Tertiary    ISSN/ISBN    Availability    Author/Address    Accession Number    Language    Classification    Sub file/Database    Original Foreign Title    Links    DOI    Call Number    Database    Data Source    Identifying Phrase    Retrieved Date    Shortened Title    User 1    User 2    User 3    User 4    User 5    User 6    User 7    User 8    User 9    User 10    User 11    User 12    User 13    User 14    User 15
>
> A row in the output file is like this:
> (The tab is successfully inserted. But I don't get why I have L inserted after no matter what I put in escapechar)
>
>     LReference Type    Authors, Primary    Title Primary    Periodical Full    Periodical Abbrev    Pub Year    Pub Date Free From    Volume    Issue    Start Page    Other Pages    Keywords    Abstract    Notes    Personal Notes    Authors, Secondary    Title Secondary    Edition    Publisher    Place Of Publication    Authors, Tertiary    Authors, Quaternary    Authors, Quinary    Title, Tertiary    ISSN/ISBN    Availability    Author/Address    Accession Number    Language    Classification    Sub file/Database    Original Foreign Title    Links    DOI    Call Number    Database    Data Source    Identifying Phrase    Retrieved Date    Shortened Title    User 1    User 2    User 3    User 4    User 5    User 6    User 7    User 8    User 9    User 10    User 11    User 12    User 13    User 14    User 15
>
>
> Any help or pointers would be greatly appreciated!
> ~Bohyun