find more than one element in a 1D array

[larson09]

Hello!

I have a 1D array with 0's and1's...i want to obtain a vector with the position all of the 1's element.....i've tried to do with search 1D array...but when this block stops when find the first 1. There is a block for buildind this vector? How i can do to make something like this?

Thanks!

larson

[becktho]

Hi larson

The function "Search 1D Array" has three inputs. The array, the value to search and the start-index. Start-index means, the search for given value starts at this position. So if you want to search multiple elements, just use this function in a loop and set start-index depending on the output of the function.

Hope this helps.

Thomas

[larson09]

Hello becktho,

i've yet thought in this way but i don't know how i have to build this code using a loop, i don't knowhow hange the index array of the new array where i want to place the position of the elements.

Thanks!

[Chaos]

If I understand you correctly you would like to get the indexs of all the 1's (true) from the original array into a new array?  If so you can try out the below example (LabVIEW 7.1) or see the picture attached.  If not please clarify what you are wanting as an output...

[altenbach]

Here is a simple example (LabVIEW 7.0).

Message Edited by altenbach on 10-24-2005 09:00 AM

[altenbach]

Additional comment:

If you are dealing with huge arrays, the "built array" node will slow you down due to memory re-allocation issues. For a much more efficient version, you can re-use the input array for the indices, then truncate it at the end using "reshape array".

Attached is a simple example, LabVIEW 7.0.

Message Edited by altenbach on 10-24-2005 09:18 AM

[becktho]

And here's another one..

[altenbach]

Becktho, you're building an array with unknown final size which causes possible performance issues due to memory allocations IF the arrays are big.

True, I don't need the second shift register and can use the iteration terminal directly instead. (Also note that "reshape array" is a better and more efficient method to truncate an array instead of using "delete from array").

Message Edited by altenbach on 10-24-2005 10:47 PM

[becktho]

Hi Christian

The aim of my post was not to start the challenge who may code it better in terms of memory usage, execution time and speed, etc. I just simply wanted to show another way.

I'm aware of the fact of memory allocation and there are different ways to handle that. By the way - I think it is not the best way to replace the elements of the original array (although I can follow your code and although it is still possible to get the original values).

I think we should encourage others to think about different solutions - and not just this unique solution where memory usage is at 0.1%, processor load at 100% (we don't want to waste processor capacity)... I think you know what I mean. Often a more logically built vi is better for newbies than an extremly efficient one. I also think that you agree with me, if I say that there is not a best solution.

By the way - if you say that "reshape array" is better than "delete from array" - could you give numbers? Ok let's forget about the generation of the last element's index I've done in my vi - just the functions itself. For sure I'm not the ultimate programmer and there are lots of guys that are more experienced than me - but just saying "this function X is better than this function Y" without numbers or something similar - wow - that's quiet brave.

Don't think I can not be criticised and I don't want to criticise you. I've learned a lot from your posts (and I'm still learning), but I think the forums should not become the place to find out who is the best programmer (what sometimes seems to be the case). Don't link this to you - it's just something I sometimes feel when I have a look at a post.

Thomas

[binoy]

you can do this in another way also. Try this vi.