CSV Tools

Some tools for working with and analysing CSV files, including:

• csvproject: project columns from a CSV file
• csvreport: output a report for each column showing the type of data, number of empty values, and so on.

Usage

Here’s an example input file:

# test.csv:make,model,derivativeford,capri,2.0Lford,capri,3.0Lcitroen,ds,2.3L

csvproject

Project as in projection. Select and output columns from the input file.

$ csvproject test.csv -c makefordfordcitroen
$ csvproject test.csv -c make -c derivativeford,2.0Lford,3.0Lcitroen,2.3L
$ # exclude columns instead of including:
$ csvproject test.csv -e modelford,2.0Lford,3.0Lcitroen,2.3L
$ csvproject test.csv -c model --headers-outmodelcapricaprids
$ csvproject test.csv -c 1 --no-headersmodelcapricaprids
$ # here's an example using stdin:
$ csvproject -c make < test.csvfordfordcitroen
$ # use a tab delimiter:
$ csvproject -d$'\t'< test.tsvford,capri,2.0Lford,capri,3.0Lcitroen,ds,2.3L

csvreport

Generate a report showing the range and type of values for each column selected

$ csvreport test.csv -c makeColumn: make┌────────────────────┬────────────────────────────────────────────────────────────┐│ Type │ String │├────────────────────┼────────────────────────────────────────────────────────────┤│ count │ 3 │├────────────────────┼────────────────────────────────────────────────────────────┤│ min │ citroen │├────────────────────┼────────────────────────────────────────────────────────────┤│ max │ ford │├────────────────────┼────────────────────────────────────────────────────────────┤│ minLength │ 4 │├────────────────────┼────────────────────────────────────────────────────────────┤│ maxLength │ 7 │├────────────────────┼────────────────────────────────────────────────────────────┤│ Unique strings (2) │ ford, citroen │├────────────────────┼────────────────────────────────────────────────────────────┤│ emptyCount │ 0 │└────────────────────┴────────────────────────────────────────────────────────────┘

TODO

• Write usage docs.
• Support files without a header row.
• Support input from stdin.
• Write some tests.
• Add flag to exclude columns instead of including.
• Improve test coverage.
• Support passing options from a config file.