mogenson/ploot

Plot streaming data from stdin to a tty terminal

Ploot

Plot streaming data from stdin to a tty terminal. Useful for displaying data piped from a serial port or long running process.

Project used to be called ttyplot-rs.

Install

$ git clone https://github.com/mogenson/ploot.git
$ cd ploot
$ cargo build # or cargo install --path .

Usage

Pipe data from a process into ploot. Press ctrlc to quit.

Data format

Each line of data points can be positive or negative floating point numbers, separated by spaces. Ex: 1 2.3 -4.56. A new frame of one to multiple series of data points is shown when a newline character is received. Statistics like minimum, maximum, average, and current value are shown for the visible data for each series.

Options

-m, --min <min>        Lower bound of window (default: largest data point in window)
-M, --max <max>        Upper bound of window (default: smallest data point in window)
-w, --width <width>    Number of data points to display in window (default: terminal width)
-f, --file <file>      Log received data to file in CSV format

Copy ploot.bash to /usr/share/bash-completion/completions for command line tab-completion of options. A bash completion script can also be generated with the --completions flag.

Examples

# build example program
$ rustc feed_input.rs
$ ./feed_input | ploot

# serial port
$ cat /dev/ttyUSB0 | ploot

# CPU percentage
$ sar 1 | awk '{ print 100.0-$NF; fflush(); }' | ploot 

# ping time
$ ping 8.8.8.8 | awk -F '[= ]' '{ print 0+$(NF-1); fflush(); }' | ploot

# bash saw wave
$ for ((i=0;; i++)); do echo `expr $i % 20`; sleep 0.1; done | ploot 

Acknowledgment

Inspired by ttyplot. Some difference include: ploot can plot negative values and an arbitrary number of concurrent series, data window width can be specified, data points are plotted with points instead of bars, data rate is not calculated or plotted.

ploot's Issues

CPU usage?

Thanks for making this.

I compiled it successfully on macOS 10.15.6.

I was trying to use it to plot kernel memory usage over time, using this command:

if sudo -v; then while true; do \
  sudo zprint |\
  awk '$1~/^kalloc/ { sub("K","",$3); sum+=$3; } END { print sum; }'; \
  sleep 1; \
  done |\
  ploot; \
fi

I noticed my fans start to spin up like crazy so I checked Activity Monitor. I saw ploot using 99-100% CPU.

To rule out sudo, awk, zprint as possible culprits, I retried using a simple counter:

c=0; while true; do (( c++ )); echo $c; sleep 1; done | ploot

Same result. Any idea why this could be? Do I need to capture a spindump etc?

[feature] log to file

Add option to log received data to a file in CSV format.