Re: EDD/DM: Passing multiple arguments for color rule definition ?

["Anna M. Estes" <a.m.estes@larc.nasa.gov>]

> 
> Hi,
> 
> 
> In the EDD/DM I need to implement color rule which represents the
> highest alarm severity of two channels.
> 
> Then I didn't found how to pass two or more arguments to the rule (is it
> possible at all ?)
> 
> Any ideas welcome.
> 
> Thanks in advance,
> Marian
> 
> --
> Marian Zurek
> CERN/ECP-CO
> 

Hello Marian,

Yes, it is possible to pass more than one argument.  However,
you can't directly compare one alarm severity to another since
the right hand terms (the terms following the comparators)
are basically constants.

In the modify property page for the item in the "color rule
arguments" field, you can enter something like:
	A=chan1.SEVR, B=chan2.SEVR
	
Your color rule definition could be something like:
	$(A) 	equals 		MAJOR	and
	$(B) 	less than 	2  	use 	<A>B color>
	$(A) 	equals 		MINOR 	and
	$(B) 	equals 		NONE 	use 	<A>B color>
	$(B)	equals 		MAJOR	and
	$(A)	less than 	2	use	<B>A color>
	$(B)	equals 		MINOR	and	
	$(A)	equals 		NONE	use	<B>A color>
	

Note that the color is selected on a "first match" basis,
Also comparisons are done based upon the type of entry, i.e. 
if a string is in the third column, the value of the first
column will be compared using a string compare and a numerical
compare will be done otherwise. It's awkward since you have to 
define all possible comparisons separately.  

Let me know if you have more questions.

Deb

p.s.  For the next generation EPICS gui, we plan to implement a more 
flexible expression evaluator for color rules, visibility,
and value conversion.

**********************************************************************
Deb Kerstiens		dkerstiens@lanl.gov
Phone			(505)667-3396
LANL AOT-8,MSH820	PO Box 1663, Los Alamos, NM. 87545 
**********************************************************************


Anna Estes
Computer Sciences Corporation
NASA Langley Research Center
a.m.estes@larc.nasa.gov
(757) 766-8266