Installation
RainPro is shipped as an APL workspace containing a large number of sample functions, and two namespaces ch and PostScrp which contain everything that you will need in order to use it from your application. A standard Windows help file is also enclosed, containing an on-line version of this manual. Simply copy the workspace to your normal development directory, and place the help file wherever you find convenient.

To access the workspace, )load it in the usual way. You will be able to try a selection of examples immediately. To access the help file, double-click it in Explorer or add a desktop shortcut which starts it for you.

Learning by example!
By far the best way to learn RainPro is to copy and modify the examples! When you load the workspace, you will be directed to a selection of variables (such as Help) which simply list the examples for you so that you can take the cursor to the line of your choice, and <Enter>. All the sample functions place the finished chart in the variable PG, so all you need to do to see the result on screen is View PG. Experiment with ‘zoom-in’ using the left mouse button (drag a rectangle across the area you want to magnify), and try out the right-mouse menu for printing options. See Using the Chart Viewer for more detail.

If you need help on the terms used throughout Rain, the glossary illustrates many of the concepts.

Building charts into your applications
When you are comfortable with the basics, you will want to use the graphics in your own GUI application. Because Rain runs the code entirely out of the ch and PostScrp namespaces, all you need in your workspace are these two objects. For example:

   )load myws
   )copy rainpro ch PostScrp

This allows you to make your plot in myws, as a vector of PostScript code. Assuming you want to see it on screen, you could to use the PS object (see causeway.hlp for more details) which will display the result for you, and provide the same options as PostScrp.View when the user uses the right-mouse menu on the chart.

For an introduction to the capabilities in ‘Active Rain’ (which are also supported by the Causeway classes) please turn to the notes on the new functions supported by the PostScrp namespace.

Note that PS is careful to preserve the proportions of the chart – these are 4:3 by default – so either ensure your PS field has this shape, or note the shape you make it and use ch.New 0 0 w h to get your chart drawn to fit the hole on the screen! See Multiple Plots for more details.

If you are just playing around, simply copy the View function from Rain. To include the charts in your APL application (without using any Causeway classes) you can render the chart on any Windows control which supports graphic objects as children. See RawGui for details.

Note that Rain is a language, and is intended for APL programmers, not end-users! If you want to build a friendly front-end with colourful toolbars and pull-down choices, that is fine, but please acknowledge the use of RainPro in the ‘About’ box for your finished application.