It is possible to execute contitionally some instructions, interactively or in command files or programs, using the commands si... and is.... Inside programs it is better to use conditional jumps (cf. 4.8.2). For instance suppose you type
- interpcom -> si ccc
where ccc is a variable name. In this case the interpreter will evaluate ccc. If the result is 0 or negative, the commands that follow will be ignored, until the interpreter receives the command
- interpcom -> is ccc
and then the commands will be again accepted. It is also possible to avoid the following instructions if ccc is positive, by using
- interpcom -> si non ccc
Example :
- interpcom -> c=1
1.000000
- interpcom -> d=-1
-1.000000
- interpcom -> a=24
24.000000
- interpcom -> si c
- interpcom -> a
24.000000
- interpcom -> si d
- interpcom -> a
- interpcom -> is d
- interpcom -> a
24.000000
- interpcom -> si non d
- interpcom -> a
24.000000
- interpcom -> is d
- interpcom -> is c
The maximal number of current conditions (not closed with is...) is fixed in the initialization file (cf. 3.1).