chart

Quick & smart charting for STDIN

Blogpost

Learn by example!

Cheatsheet

Syntax

chart [options]

• pie: render a pie chart
• bar: render a bar chart
• line: render a line chart
• scatter: render a scatter plot chart
• log: use logarithmic scale (bar chart only)
• legacy-color: use legacy colors
• gradient: use color gradients
• ' '|';'|','|'\t': this character separates columns on each line (\t = default)
• -t|--title: title for the chart
• -x: label for the x axis
• -y: label for the y axis
• --date-format: Sets the date format, according to https://golang.org/src/time/format.go
• --debug: Use to make sure to double-check the chart is showing what you expect.
• -h|--help: Show help
• --zero-based: Makes y-axis begin at zero

Installation

go get -u github.com/marianogappa/chart

or get the latest binary for your OS in the Releases section.

Example use cases

• Pie chart of your most used terminal commands

history | awk '{print $2}' | chart

• Bar chart of today's currency value against USD, in logarithmic scale

curl -s http://api.fixer.io/latest?base=USD | jq -r ".rates | to_entries| \
    map(\"\(.key)\t\(.value|tostring)\")|.[]" | chart bar log -t "Currency value against USD"

• Bar chart of a Github user's lines of code per language (requires setting up an Access Token)

USER=???
ACCESS_TOKEN=???
curl -u $USER:$ACCESS_TOKEN -s "https://api.github.com/user/repos" | \
    jq -r 'map(.languages_url) | .[]' | xargs curl -s -u $USER:$ACCESS_TOKEN | \
    jq -r '. as $in| keys[] | [.+ " "]+[$in[.] | tostring] | add' | \
    awk '{arr[$1]+=$2} END {for (i in arr) {print i,arr[i]}}' | \
    awk '{print $2 "\t" $1}' | sort -nr | chart bar

• Line chart of the stargazers of this repo over time up to Jan 2017 (received some attention after the publication of this blogpost)

curl -s "https://api.github.com/repos/marianogappa/chart/stargazers?page=1&per_page=100" \
-H"Accept: application/vnd.github.v3.star+json" | \
jq --raw-output 'map(.starred_at) | .[]' | awk '{print NR "\t" $0}' | \
chart line --date-format 2006-01-02T15:04:05Z

Charting MySQL output

chart works great with sql, or with any mysql -Nsre '...' query.

I don't trust the chart is correct

Me neither. Add --debug to double-check (e.g. some rows could be being ignored due to parse failures, separator could be incorrect, column types could be inferred wrongly).

$ cat /tmp/c | ./chart bar --debug
Lines read  3
Line format inferred    ff
Lines used  3
Float column count  2
String column count 0
Date/Time column count  0
Chart type  bar
Scale type  linear
Separator   [tab]

Details

• chart infers STDIN format by analysing line format on each line (doesn't infer separator though; defaults to \t) and computing the winner format.
• it uses the awesome ChartJS library to plot the charts.
• when input data is string-only, chart infers a "word frequency pie chart" use case.
• should work on Linux/Mac/Windows thanks to open-golang.

Known issues

• Javascript's floating point messes up y-axis https://github.com/marianogappa/chart/issues/15
• No histogram support (ChartJS doesn't provide it) https://github.com/marianogappa/chart/issues/22

Contribute

PRs are greatly appreciated and are currently being merged. If you have a use case that is not supported by chart, I'd love to hear about it, but if it's too complex I'd recommend you to try gnuplot.

Development

• Requires Go version >= 1.11 with module support for building and testing.

• Requires Goreleaser for building and publishing releases.

• See Makefile for build and test commands.