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numeric case structure

Im having a hard time creating a numeric case structure that has the following cases:

<1
between 1 and less than 2
between 2 and less than 3

It seems that this will not work using 1..2, for example, because that 2 will also fall in range of case 2..3

Please advise

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Message 1 of 9
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Well the main problem is that the selector on a numeric case structure is an integer. Notice the red coercion dot appears when you wire a float to the selection? Hence there are no values between 1 and less than 2, or between 2 and less than 3.

One thing you can do is rescale your float and then convert it into an integer. For example, say you multiply your input value by 1000. Now you can have ranges that approximate what you are wanting:
..999
1000..1999
2000..2999
3000..
Alternately you can use comparison functions with nested boolean case structures. (I prefer the first solution - less complicated.)

Mike...

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Message 2 of 9
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Just round to -infinity and convert to integer.
 
Make the cases:
 
"..1" for anything below 1
"1" for 1 .. 1.9999999999999999999
"2" for 2 .. 2.9999999999999999999
etc.
Also add a default case.
 

Message Edited by altenbach on 07-21-2007 10:37 PM

Message 3 of 9
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Hi Altenbach,

Atleast in LV 7.1, it is NOT allowing to add the case "1,2" after adding the case "..1". It tells that the case structure values are NOT unique.

Please see the attached VI & clarify me...

- Partha ( CLD until Oct 2024 🙂 )
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Message 4 of 9
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Sorry, the first case needs to be "..0" of course. You cannot have the "1" in two different cases.

Your lower case structure is also wrong, because you have overlapping ranges. For example an input of 0 will match both "..1" and "..2". Right? For any given input, there can only be exactly one matching case or you get an error.

Message Edited by altenbach on 07-23-2007 12:08 AM

Message 5 of 9
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Thanks guys

Yes the problems of overlapping and using non-integers are certainly there and, knowing that I will allow the user up to three decimal places, I used the suggestion of multiplying by 1000, which worked great, so its "..1000" , "1001..2000", etc.

Thanks guys for your help
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Message 6 of 9
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Hi guys,

I want to have a case structure with two cases one is when the number is infinity and else, can you give me ideas how to do such a case structure thank you

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Message 7 of 9
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Question was put into a new thread:

http://forums.ni.com/t5/LabVIEW/case-strucute-with-infinity-and-else-as-two-cases/m-p/3206092/highli...

 

Please proceed discussion there.


Norbert

Norbert
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Message 8 of 9
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You can type "inf", "-inf" into float numerics. Also there are special constants in numeric palette. Then comparison function

PS I would start a new thread, ksm is very surprised now, his 8 years old question...

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