Scripts

ViDAL -- ViSta's Data Analysis Language -- lets you define script files so that you can run analyses automatically without requiring user interaction.

ViDAL also lets you type at the keyboard rather than use the point-and-click graphical interface.

• ViDAL consists of functions which correspond directly to menu items. Every menu item is paralleled by an identically-named function (except spaces are replaced by dashes).

• For example, (show-variables) is the ViDal function that corresponds to the Show Variables menu item and GuideMap button.

• ViDAL can be used by typing at the keyboard, or it can be used as a script loaded from a file.

Here is a simple ViDAL example:

(load-data "animals")
(visualize-data)
(analysis-of-variance)
(report-model)
(visualize-model)

These ViDAL functions load the "animal" data, visualize them, then do an analysis of variance, followed by a report and visualization of the resulting anova model.

Advantages of ViDAL:

• Sophisticated Users may only need ViDal, as they may be most satisfied with typing commands.

• They may not wish to use a visual interface all the time (or ever). ViDal permits this.

• The direct and simple correspondence of menu items, GuideMap buttons and ViDAL functions is meant to gradually teach users the underlying ViDAL language, gradually increasing the sophistication of the data analyst.

• ViDAL permits scripts so that repetitive or long analyses may proceed without the necessity of have a user present.

• ViDAL scripts permit learning-by-example tutorial sessions. Examples are provided with the system.