Using this Manual
The chapters included in this manual provide a "hands-on" way to learn basic IDL concepts and techniques. Getting Started with IDL demonstrates a number of common IDL applications; each section introduces basic IDL concepts and highlights some of the commonly-used IDL commands.
Each chapter functions similarly to a tutorial and is a demonstration of a particular IDL feature. It is recommended that you walk through each short, interactive chapter to preserve continuity, since many commands rely upon previous commands. Each chapter assumes the most basic level of IDL experience.
A Note on the Example Code
You don't have to read all of the descriptive passages that accompany each chapter. Simply click the blue example code to execute it in IDL, or enter the IDL commands shown in courier type at the IDL Command Line (the "IDL>" prompt) and observe the results. Unless otherwise noted, each line shown is a complete IDL command (press RETURN after typing each command). If you want more information about a specific command, you can read the explanations or consult IDL's online help system by selecting Help → Help Contents in the IDL Workbench.
Tip
The dollar sign ($) at the end of a line is the IDL continuation character. It allows you to enter long IDL commands as multiple lines.
A Note on the Graphics Displays
Many of the examples in this manual use IDL's iTools, which provide an interactive graphical interface to visualizations such as plots or images. The iTools use IDL's Object graphics system, and will automatically adjust to display correctly on any computer running IDL.
Other examples use IDL's Direct graphics routines (which have names like PLOT, CONTOUR, or TV). The Direct graphics system is simpler to use in some situations, but lacks some of the display management features of the Object graphics system. As a result, on most newer systems you will want to tell IDL to use a maximum of 256 colors in its graphics displays by entering the following command at the IDL command prompt:
