LabVIEW
help with array manipulation
Solved!
Why are you scattering LOL thoughout your message? It makes it seem like you don't take yourself or your question seriously and makes your message kind of annoying to read. Save the "LOL's" for when you are text messaging your BFFs.
What does the term "PEN" mean? When composing a message, please don't use obscure abbreviations without defining them.
I'm trying to decode what you are saying through all that chuckling to yourself. It seems that your VI is building a lot of data into an array, but sometimes you get data that is zero, and you don't want that placed into the array, just ignored. Is that correct?
What you need to do is use a shift register to store your 2-D array rather than auto-indexing it at the loop output tunnel. Initialize it with an empty array. If you get data you want to put into the array, then in the true case, build that new data onto the data in the shift register and pass it back into the shift register. If you get the zero and that is the data you don't want to store, then pass the 2-D array wire through the False case so the array remains unchanged.
By the way, in your VI, you don't need to branch your 1-D array into 3 Index Array functions to get the elements. You can feed the array into a single Index Array function, stretch the bottom of the function down until you get 3 elements. With a single function, you will automatically get elements 0, 1, and 2 and you won't even have to wire constants to them.
Also, there is a greater than zero function already on the comparison palette. That way you don't need to use a greater than and a separate 0.
Don't need to branch your i wire inside the loop and have it go through two different tunnels, you are just duplicating data. Use 1 tunnel and branch the wire outside.
Don't clear your DAQ task on every iteration of the loop. Just clear it when the VI ends.
Wire a control to your Stop terminal. Having a False constant there means you are forced to Abort the VI to get it to end.
I don't know what your Not Sure VI is supposed to be. I'm not sure why you are associating your HP instrument with a DAQ task. They are two completely different entities.
Here is the VI with all these things changed.
The forums aren't necessarily serious all the time, but they should be kept professional. I just felt that the LOL's you were adding really distracted from trying to read and understand what you wanted to do. Unclear messages really don't help you, or help us trying to help you. I often read messages as if I was hearing the person talk to me right in front of me. And if someone was trying to ask me an important question but kept laughing during the whole thing, it would be so distracting I'd want to smack them and walk away.
I would consider shift registers to be the better way to go with most LabVIEW code constructions. I don't think you should try to avoid them. But I think the way to do what you are looking for is to go ahead and build the array with all the unwanted data in it. Then when you are done, you could use functions like delete from array as you iterate through the searching each row and deleting it as necessary. But even then you will need to use a shift register to maintain that array since you will be working on the array in a loop. So no, I can't think of a way of doing this without shift registers.
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jaswri wrote:Side note -- What I was hoping some one suggest is a way to do this not using shift registers. I took the clad and am taking the cld soon and just wanted to expand some of my knowledge.
The use of shift registers is correct here. Shift registers are one of the most efficient data structures in LabVIEW and mastering them is a key skill you will need.
The code could be made more efficient if you know from the start of the program exactly how big the final arrays will get, but I don't think this is possible in this case.
