EILEEN CHURCH CARSON wrote:
> I want to write a program that reads in data from two csv files with 6
> columns each. I want it to determines if the data in the first two columns
> is the same, and if so read all six columns in that line from each of the
> two files into a 12 column output file.
>
> Please let me know if you know of specific resources or python commands
> that will help me do this.
Use the csv module to read and write your data.
Read one csv file into a dict that maps the two key columns to the complete
row. Then when you read the other csv file you can look up the corresponding
record in the dict. Here's a sketch of the part tha performs join*:
for row in ...:
try:
other = lookup[row[:2]]
except KeyError:
# no corresponding data found, ignore row
pass
else:
# write combined row
# result_writer is a csv.writer() instance
result_writer.writerow(row + other)
Come back with your code when you need more hints.
(*) If you know some SQL another option is to read the two csv files into an
sqlite3 db -- sqlite3 is also part of the standard library.
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