pluckr

Pluck columns from csv files in the commandline. Like cut or awk, but without choking on delimiter escaping.

install

pip install pluckr. Done.

usage

Grab columns 2 and 3 from stdin (-f is one-indexed):

pluckr -f 2,3 < sample1.csv

Or straight from a file:

pluckr -f 2,1 sample1.csv

Your requested order is retained:

pluckr -f 1,2 sample1.csv != pluckr -f 2,1 sample1.csv

You can use Python's negative indices... grab the first and last cols:

pluckr -f 1,-1 sample1.csv

And you can mix in ranges for column selection:

pluckr -f 2,4-6,9 sample1.csv

Can't be sure which columns exist or what their indices are?

pluckr --names sample1.csv

Fields that don't exist (e.g. -f11111) will be ignored.

Preprended line numbers can be helpful:

cat sample1.csv | pluckr --line-numbers

Skip header row(s):

cat sample1.csv | pluckr -s1

Grab all but the 2nd column (drop columns instead of selecting them):

pluckr -f 1 -i < sample2.csv

Read (and write) various delimiters:

pluckr -d, --out-delimiter=\| < with-commas.csv > with-pipes.csv

Note that passing tabs as arguments can be awkward; in a pinch, use:

pluckr -d $'\t'

help

Via --help:

usage: pluckr [-h] [-f FIELDS] [-i] [-d DELIMITER] [-q QUOTECHAR] [-s SKIP]
              [-l] [-n]
              [infile]

Grab columns from csv input. http://github.com/philadams/pluckr

positional arguments:
  infile                input file (.csv)

optional arguments:
  -h, --help            show this help message and exit
  -f FIELDS             ordered list of columns to retain; one-indexed
  -i, --inverse         invert column retention: drop those in -f
  -d DELIMITER, --delimiter DELIMITER
                        field delimiter when reading infile
  -q QUOTECHAR, --quotechar QUOTECHAR
                        field quotechar when reading infile
  -s SKIP, --skip SKIP  number of rows to skip
  -l, --line-numbers    prepend line numbers to output
  -n, --names           print column names; assumes one header row

tests

This project uses roundup for testing. Run tests with make test.

future

• allow -f to take columns by name when there's a header row?
• implement --out-x for output delimiters etc.
• json output? or, contribute a cli to kennethreitz/tablib
• add out delimiter support
• add out quotechar support