学习IDL编程的一个学习资料，介绍了IDL函数对于各种图像操作的方法，附有部分代码-Learning IDL programming a learning information on the IDL function methods for a variety of image manipulation, with part of the code

ENVI学习的基础教程，同时里面引用IDl的基础学习-ENVI Learning Essentials, which also references the basis for learning IDl