Loon: An Interactive Statistical Visualization Toolkit


loon is written in Tcl and Tk. Users familiar with Tk widgets will feel familiar with the loon API as the loon widgets follow the standard Tk conventions.


The loon package has no compiled code and hence installation only requires to move the loon package to a place where the Tcl interpreter looks for packages (inspect the auto_path Tcl variable).

Get the package from github

git clone https://github.com/waddella/loon.git

You can use the loon package immediately (without installation): change your working directory as follows

cd loon/Tcl/

start tkcon and source the load.tcl file as follows

tkcon load.tcl

If you need to import images from jpeg and png files you also need to load the Img package

package require Img

The following line in load.tcl

namespace import loon::*

imports all of loon's (exported) commands into the global namespace. If you do not import loon's procedures into the global namespace then you need to prepend loon:: in front of loon's procedure names (e.g. loon::plot instead of plot).

Getting Started

Once the package is loaded (i.e. with the load.tcl script) an example scatterplot is created as follows

plot -x {4 1 5} -y {2 3 1} -color {red orange blue} -size {1.4 5.2 4}

If you want to use loon interactively via the tcl shell take a look at the tk console tkcon.

The user interfaces of loon's displays are explained in the UI section.