Index Last Element of Array

[JB]

A new function that indexes the last element of an array would spare some place on the diagram or avoid to use a subVI !

Or the Index Array function might be enhanced (First, specified Index and Last).

[elset191]

A somewhat related idea was submitted some time ago that might be of interest to you.  There's also a good discussion on why or why not it would be a good idea.

[AristosQueue (NI)]

Just insert a Reverse 1D Array prim before the Index Array and leave the index unwired. The Reverse 1D Array does *not* make a copy of your array... it just annotates the output that this array should be walked backward.

[jgcode]

I use the Delete Primitive's deleted element.

By default it spits out the last element in an array

I am under the impression it doesn't make a copy - maybe someone could confirm.

[Darin.K]

Showing Buffer Allocations seems to imply that the Delete Element primitive does make a copy, even when the Array Output is not connected.  Not sure why it would have to though.

[JB]

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Aristos Queue a écrit :
Just insert a Reverse 1D Array prim before the Index Array and leave the index unwired. The Reverse 1D Array does *not* make a copy of your array... it just annotates the output that this array should be walked backward.

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Yes, this way is well known to me.

Because indexing the last element of an array is a very often used task, my main purpose is to spare as much as possible space on the diagram. Reverse 1D Array takes less place than Array Size + Decrement but still much more than an "all-in one" function would.

[crash_override]

What I do is I increment a shift register variable or if there are multiple indices I need to keep track of I have a separate array of indices which I increment every time I add to the array. This approach works for me.

[crossrulz]

As of LabVIEW 2014, the fastest way to get the last element of an array to use the Delete From Array.  In 2012, I apparently found a bug where the DFA did not "stomp" an unwired array output.  Some background can be found here: https://lavag.org/topic/16226-new-array-vi/ 

[zou]

The Reverse 1D Array doesn't work for 2D array.

Need get last row/column of 2D array.

[crossrulz]

Zou,

If you use Delete From Array, it will default to removing the last row (ie the "deleted portion" output will be the last row).  So if you want the last column, use a Transpose 2D Array before the Delete From Array.

[zou]

But I don't want to make a copy of a big 2D array.