### 10.1.1 The program editor

Xcas provides a program editor, which you can open with Alt+P. This can be useful for writing small programs, but for writing larger programs you may want to use your usual editor. (Note that this requires an editor, such as emacs, and not a word processor.) If you use your own editor, then you will need to save the program to a file, such as myprog.cxx, and then load it into Xcas with the command line command load, as in load("myprog.cxx").