Visualization

There are a few tools that are useful for quick and dirty visualization.

Sparklines

sparklines is a small tool (and python module) for quick numeric visualization:

seq 10 | gshuf | sparklines

▂▅▄▃▆▁▇█▃▆

Misc

Progress bars in pipes

Sometimes I am sending a lot of data through a pipeline, and I’d like to have an idea of how quickly it is proceeding, or if it’s still going at all.

There’s a useful command that I discovered for this called pv. brew install pv or apt-get install pv

seq 50111222 | pv -lapbet | wc -l
 23.1M 0:00:07 [3.29M/s] [                  <=>

pv can produce a little curses progress meter that updates as you go. It has a lot of formatting options, including the lines format, the default bytes format, ETA and other goodies.

You can also create a trivial monitor in perl:

# print the line number ever 1MM lines
perl -pE'say STDERR $. if $. % 1_000_000 == 0'