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calculating execution time

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I'm trying to test the execution time on a subvi before I implement it a larger design into another VI.  It's testing the time difference between using a mathscript node and the labviews native math functions.  However, I am not able to get any kind of time delay using the tick count function.

 

Attached is my code, I'm using labview 8.2

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Your code is not attached.  I'm sure the native LabVIEW functions will be much quicker.  But if the calculation is quick enough, you might not see a difference.  Try doing the calculation repeatedly with a For Loop a thousand times, or a millions times, to magnify the time of execution.
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ooops I'm sorry, here it is attached.  I've tried running the for loop for over 10,000,000, and can see a delay in executing physically, but it will not calculate.  I can not figure out why.
Message Edited by JJJOndae on 05-23-2010 09:14 PM
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Formula execution will be far less than 1msec. 2344324786343 - 2344324786343 = 0

 

For this sort of testing you will need to call the function multiple times, start with 10,000 and keep increasing until you can see the differences.

Drop a for loop into the centre of your sequence structures.

iTm - Senior Systems Engineer
uses: LABVIEW 2012 SP1 x86 on Windows 7 x64. cFP, cRIO, PXI-RT
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Try this instead, and yes, there is a significant difference.
iTm - Senior Systems Engineer
uses: LABVIEW 2012 SP1 x86 on Windows 7 x64. cFP, cRIO, PXI-RT
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Thank you for the help, but could you somehow save the file in a version that will allow me to open?  I'm using 8.2 (ancient I know :D)
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Oops, My Mistake.

 

Labview applies constant folding and optimises a fair bit of this code out.

iTm - Senior Systems Engineer
uses: LABVIEW 2012 SP1 x86 on Windows 7 x64. cFP, cRIO, PXI-RT
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Solution
Accepted by JJJOndae
lv 8.2
iTm - Senior Systems Engineer
uses: LABVIEW 2012 SP1 x86 on Windows 7 x64. cFP, cRIO, PXI-RT
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Wow, this works absolutely perfect.  That is a genious idea what you did there, I don't think I would have ever thought of that.  And I can see now my mathscript will execute much quicker.  Thanks so much!!
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Message Edited by Dennis Knutson on 05-23-2010 09:13 PM
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