turn array of integers into a ranges list

[tshurtz]

I am looking for a clean way to turn an array of integers into a ranges list.

turning this into this  or at least this 

I am hoping there is a VI already somewhere in the bowels of Labview that I can use as this is essentially what is happening in the case structure selector label if you list many integers and some are consecutive.

Anyone know where I might find this magic vi? I can write my own but if its already available all the better. 

[RavensFan]

I doubt it,  you'll likely have to code it yourself.

Should be a fairly simple loop with just a couple case structures.

You need to know when you are starting a run of numbers, ending a run of numbers, or still in the middle.

Step through element by element.  If the next element is equal to the current element + 1, you know you are in a run.

[billko]

I know the case structure will automatically do that for you.  I wonder if there's a way to leverage that information somehow...

[paul_cardinale]

I made this ages ago.

[altenbach]

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@tshurtz wrote:

Anyone know where I might find this magic vi? I can write my own but if its already available all the better. 

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I am sure this has been solved before here in the forum. But should be trivial to implements if we can make certain assumptions:

• Is the array guaranteed to be sorted?
• Are there no duplicate elements?

Assuming the input is clean, this might work for you. There are many other ways.

[tshurtz · Accepted solution]

@altenbach

Thanks,

I made a few minor modifications to handle a few more fringe cases.

- I made a case if the array is empty to return a blank string

- I sorted the array so that out of order isn't an issue

- I added "0" to the -1 case (compared to difference between current and last value) to ignore repeat values

Thanks again 

[altenbach]

As I said, it really depends how clean the input array is and additional code might be needed.

One request thought. Please give a VI a new name when attaching a new version. It can lead to serious confusions if a thread contains multiple different VIs, all with the same name.

At this point I would suggest to turn it into a malleable VI (vim), correctly accepting any integer datatype. (only available in recent versions, but alone worth the upgrade!)