property node, does the order play a role?

[wisi]

Hello
At the beginning of my program, some graphs (diagramms) should be initialized. That is, I want to set the offset, maximum, step and factor of the x-axis. I know how to do this with the property node (see attachement). But now my problem is, that this works well in about 8 to 9 times out of 10. Why doesn't it always work? Does the order of the properties play a role?

[MikeS81]

Hi wisi,
yes the order is important. The property node work from top to bottom.

Mike

[altenbach]

Could you be a bit more specific on what you get when it does not work? I don't really know what to watch out for.

[wisi]

Thanks for the fast answer. So should I now change the order, to get always the same result? And if yes, which is the correct order?

[wisi]

Ah, sorry. What's not always correct is, the maximum of the x-axis. As I said, usually it's correct, but sometimes, the maximum of the x-axis is something completely wrong. As far as I know are the factor, offset and step always correct.

[altenbach]

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wisi wrote:
What's not always correct is, the maximum of the x-axis. As I said, usually it's correct, but sometimes, the maximum of the x-axis is something completely wrong.

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Can you give an example of a "completely wrong" maximum? Off by a year? different timezone? random value?

Anyway, it seems to work fine here. (LabVIEW 8.5.1)

In order to troubleshoot, you should really NOT "ignore errors inside node". Maybe it wants to tell you something when things go wrong? It also seems silly to recruit a property value to enforce dataflow. Typically we use the error cluster for that. 😉

[wisi]

I'm using LV 7.1. Usually, I want the x-axis to be something between 1 and 12 hours, and when it's off, it shows something between 1 and 3 hours. I've never got any error messages. I've just tried now, and was able to reproduce the reported wrong x-axis, but got no error message from the property node (which I displayed). And what do you mean with 'enforce dataflow'. I only use the property node once, in the beginning, to set the x-axis to the current time and date.

[altenbach]

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wisi wrote:
And what do you mean with 'enforce dataflow'. I only use the property node once, in the beginning, to set the x-axis to the current time and date.

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You are getting the Xflipped property for the sole purpose to determine execution order (init--FOR loop--while loop) while never using the actual value of it.

Seems like a waste. 😉

Typically, you would use the error cluster instead, e.g. as follows (I also did a few other simplifications):

Sorry, I cannot reproduce your problem. Maybe this was a bug that has been fixed.

Message Edited by altenbach on 06-10-2008 10:11 AM

[wisi]

ok, I understand what you mean. I agree that your version looks much more elegant. The file I presented here, was a test file, to find the source of the problem, and is not supposed to be for further use. But thanks a lot, anyway. It may just be bug.