Programmatically increase sequence size

[Nizzo]

Hi everyone,

I'm fairly new to Labview and I'm having a hard time doing some fairly basic tasks.

Currently I want to programmatically change to size of a sequence. 

I need to automate a sequence of valves to open and I would like the amount of steps to change based on a number.

Currently I have 9 clusters (one per step) with a timer to change how long a step takes, however this doesn't seem the right way of doing it especially as it's not sizable. I'll attach some screenshots that will hopefully help explain. (each button is a valve)

I'm also trying to completely stop valves from opening or closing depending on some pressure sensors as if there is pressure and the wrong valve opens it could break a lot of expensive flowmeters.

Regards,

Andrea

 

 

[GerdW]

Hi Nizzo,

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@Nizzo wrote:

Currently I want to programmatically change to size of a sequence. 

I need to automate a sequence of valves to open and I would like the amount of steps to change based on a number.

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This is the wrong way to create your program/algorithm!

Instead of trying to add/delete frames in your sequence you should use a simple state machine!

Then it becomes very easy to define the number of "steps" (aka iterations) of the loop around that state machine…

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@Nizzo wrote:

I'm also trying to completely stop valves from opening or closing depending on some pressure sensors as if there is pressure and the wrong valve opens it could break a lot of expensive flowmeters.

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This also becomes very easy once you create a simple state machine! You can check your conditions in each iteration of the loop around your state machine…

Btw.:

• All those "Steps" clusters belong into an array of clusters - or even use a simple 2D array of booleans!
• When using an array of clusters: place the wait time inside the cluster. Otherwise use a numeric  array to define the time for each step…
• Why are there all those coercion dots? Why don't you define the wait time as U32?
• Why are there so many generic control labels? Why don't you define reasonable control labels?

[paul_cardinale]

It seems that you are asking how to have a program modify itself.  That's usually impossible, and where it is possible, it's almost always a very bad idea.

Instead of having a bunch of separate controls use an array.

[Nizzo]

Hi GerdW,

How would I go about using a state machine for this? 

From my understanding a state machine inside a loop just does the same thing over and over and changes depending on variables. How do I program it to give a different input each time it comes around?

My complete idea is to have this page to create/modify an automation, each "step" will then have a selection box to automate valves/motors/pumps (depending what's needed) and I can see how a state machine can take care of that. However I'm struggling to understand how a state machine can increase or decrease the number of steps, because it would do the same thing over and over if it was the iterations of the loop, or am I understanding this wrong?

Questions about your tips:

1-2) I ended up using 1D arrays for each step, However how would I go about:

   a) Getting only the time from a cluster

   b) Splitting the second dimension of the array into each step.

3) That was just ignorance, I did change it to U32 and the coercion dot went away.

4) Right now I'm just trying to figure all this stuff out. So there is a lot of changing and I've been too lazy to rename everything every time I need to restart. But everything will be labelled properly by the end.

I really wanna tank you for your help, it's very appreciated.

Regards,

Andrea

[Nizzo]

Hi Paul,

I could move to 2D arrays lie GerdW said however I would still need to change the size of the second dimension, wouldn't that still be considered changing the program?

regards,

Andrea

[paul_a_cardinale]

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@Nizzo wrote:

Hi Paul,

I could move to 2D arrays lie GerdW said however I would still need to change the size of the second dimension, wouldn't that still be considered changing the program?

regards,

Andrea

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No.  Changing data size is not changing the program.  Also, on controls that are arrays, the number of elements displayed is a property that is writable at runtime. 

[Yamaeda]

If you change those cluster into an array of cluster, most things will solve itself and you'll cut down your code by 80%.