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Stop condition expression

Posted Oct 1, 2012, 9:13 p.m. EDT Version 4.3 4 Replies

Collin Mui
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How do I set up the stop condition if I want the solver to stop when the point probe expression ppb1 is less than a value?
4 Replies Last Post Nov 2, 2012, 4:27 p.m. EDT
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Paul Coman
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Posted: 1 decade ago Nov 2, 2012, 5:58 a.m. EDT
I have the same problem.

The stop condition expression that I use is

mod1.ppb1<0.1

where mod1 is the index from the model and ppb1 is the point probe.

The expression is well evaluated and the model works but the stop condition isn't.

Does anybody know why?

Paul
I have the same problem. The stop condition expression that I use is mod1.ppb1
Paul Coman
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Posted: 1 decade ago Nov 2, 2012, 5:59 a.m. EDT
If I use

mod1.ppb1-0.1

the model stops when the point value reaches the value 0.1, therefore it works. But what about "less than" ?
If I use mod1.ppb1-0.1 the model stops when the point value reaches the value 0.1, therefore it works. But what about "less than" ?
Paul Coman
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Posted: 1 decade ago Nov 2, 2012, 6:08 a.m. EDT
Dear Collin,

I was killing my brain with this and finally I have discovered how it works.

Just write:

0.5-(modx.ppby<value)

where x and y denote the index of model and probe evaluation and the value is the desired value. My example:

0.5-(mod1.ppb1<0.02)

Dear Collin, I was killing my brain with this and finally I have discovered how it works. Just write: 0.5-(modx.ppby
Nagi Elabbasi Facebook Reality Labs
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Posted: 1 decade ago Nov 2, 2012, 4:27 p.m. EDT
You figured it out obviously. I just want to clarify one thing. The Stop condition terminates the analysis when the stop expression becomes negative. The Boolean operators like >, < evaluate to 0 (False) or 1 (True). That’s why they don’t work as you expected. Your modified expression takes care of that.
You figured it out obviously. I just want to clarify one thing. The Stop condition terminates the analysis when the stop expression becomes negative. The Boolean operators like >, < evaluate to 0 (False) or 1 (True). That’s why they don’t work as you expected. Your modified expression takes care of that.

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