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/great-northern-diver/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).
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.