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sequence locals

Hi,

I am new to Labview so please bear with my simple question.

 

I am trying to make stacked sequence structure, but for some reason  I am unable to get the arrows on the sequence locals to point in the right direction.

I have attached a snap shot of my attempt to better explain the issue. 

 

Your help is much appreciated.

 

Thanks,

Mashra

 

 

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Message 1 of 6
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DO not use stacked sequences and especially sequence locals! Unless you are experienced enough to

0) follow basic dataflow rules

1) know how they are used

2) know other methods to solve the same task

3) based on (1) and (2) you are sure stacked sequences are absolutely necessary. 

 

You violate (0) and (1), and sequence locals violate (0) in general.

Sequence local data is available (arrow "out") in the frames after the one you write data into it (arrow "in"). And obviously only within one structure, not between separate structures.

 

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Message 2 of 6
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That's because you are using a stacked sequence structure Smiley Happy

 

If you are trying to benchmark a piece of code why not use a flat structure?  But that code just going to update an indicator with the number 8 1,000 times, so no pont in bench marking that.  It would also not be a good benchmark beacuse you have the indicator inside the loop.

 

What are you trying to accomplish?

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Hi Bryan,

Thank you for your reply.

I am trying to find the time difference between two actions, once that does nothing and one that does a simple addition 1000 times. 

I am just trying to follow an example work which is trying to explain that we can do the same thing with both flat and and sequence structure.

 

What do you advise?

 

Thanks once again,

mashra

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Message 4 of 6
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Have a look at the code I did here: A Look At Race Conditions.  There are some examples in there of how to do benchmarks with the Flat Sequence Structure.


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Message 5 of 6
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Your picture doesn't show a single sequence.

The local is not in the same place in each picture, the frames are not the same size, so it's hard to tell what's really there.

 

The arrows tell you whether there's data on that terminal or not.

 

If the terminal is blank, nothing has put data into that local yet.  

 

If you put something IN to the local in frame 2, and USE IT in frame 4, then:

--- It will be blank in frames 0 and 1.  (there's nothing there).

--- In frame 2 it will be an OUT arrow (data coming OUT of this frame)

--- in frame 3, and all frames after, it will be coming IN to the frame.  You can wire it or not, but it's available.

 

Steve Bird
Culverson Software - Elegant software that is a pleasure to use.
Culverson.com


Blog for (mostly LabVIEW) programmers: Tips And Tricks

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