Experimental Physics and
Industrial Control System

Kay-Uwe Kasemir <[email protected]> · Fri, 18 May 2007 10:00:10 -0400

On May 18, 2007, at 09:45 , marco_hair wrote:
hi, all:
 I met a problem. Now I am using a BI record to get a value from
hardware, scan period is 1 second. So in 3 seconds, I will get 3
values(for example, a,b,c). I want a average value of these three
ones which will be obtained by edm, that is (a+b+c)/3. How can I
implement it by EPICS db? or is there any other ways to reach this?

The 'compress' record type could be configured to read NSAM=3 samples
with ALG="N to 1 Average" to get the average of those 3 records.
I think that's most often used with numeric values as they would
for example come from an AI record.
But it should work with your specific example, a "BI" record,
that provides binary or boolean, i.e. 0/1 values.
When you take the average of those boolean values,
for example a series 0, 1, 0,
I guess you could interpret the resulting 0.333 as a fuzzy logic
probability of 30%.
-Kay

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System