Formula in LabVIEW

Hi,
We have purchased LabVIEW 8.0 and currently working on a project based on LabVIEW. I have to write out the result from a formula calculation to a parallel port. The result of the formula is a 11 digit decimal number. I need to display the result in HEXADECIMAL format and write it to 3 16bit registers in an external board. But after executing the formula, I'm not able to convert the result to hex format.
I look forward to your reply at the earliest.
Yours faithfully,
Vishnu Rajendran,
JRF,
BCG,
CDAC Trivandrum.

Check the numeric representation of the result of your calculation. If its a float it has no hex representation - at least in the sense that an integer does.
Mike...
Certified Professional Instructor
Certified LabVIEW Architect
LabVIEW Champion
"... after all, He's not a tame lion..."
Be thinking ahead and mark your dance card for NI Week 2015 now: TS 6139 - Object Oriented First Steps

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I'm not able to open the Formula function. It says the library is not accessible. I just installed LabVIEW on this machine. Any ideas?
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Vara,
I'm with smercurio, and think that a reinstall is probably your only option. You could try to delete the files that are causing the issue and then try another repair, or you could do the reinstall and know you're going to fix it.
And Jeff is correct that in older versions of LabVIEW it was a little ambigeous what needed to be installed but starting in 8.6 we added the "Installed with:" field to the help, and it 2009 we changed the name to "Requires:". This makes it easier to know what the VIs installed with.
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Change the parameter in the formula by Labview?

I need to set up a formula (Since I need to analysis data, so everytime have differece formula, but I can't build up a new VI everytime),for example sin(a*x)*exp(b*x). If a & b & the formula are fixed, I can do it. But now, I need to make the a & b to be a set of values, like "a" is 0:1:10 and b is 50:0.1:100. That means when "a" is 0, "b" will go from 50 to 100 with step 0.1. And I need to be able to use the same VI for other formula. I try a few different way but still not able to come out the answer. Please help
====================
=Labview 7.0 & 8.0 & 8.5=
=====================

Hello asd,
for a & b parameters you have to use 2 nested loops with your formula inside and you get a 2d-array with results.
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Best regards,
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Integrate a very sophisticated formula in labview

Hello all
in my Phd i have a very sophisticated formula that i need to integrate in my labview code .
please ho know a solution that can make easy this integration in my project
please see the example attached
Solved!
Go to Solution.
Attachments:
formula.JPG ‏58 KB

You can enter it more or less straight from that text into a FORMULA NODE.
If you're interested in simplicity, that's the way to go.
If you're interested in better performance, you'll have to factor it, same as you would for any other language.
Instead of stating "2*pi*i*k" all those times, figure it once, and use it several times.
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Implementing Formula in LabView

I seem to have a rather odd problem. I just can't figure out why isn't a certain calculation (refractive index) working properly.
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Attachments:
To Post.zip ‏67 KB

I actually tried that but with no luck.
There is one thing I'm curious.
there is a line code in MatLab called: phas1=unwrap(angle(z_face1),pi).
Is that the same this as "theta" from the polar form of FFT?
I made few phone calls and managed to get the MatLab code that calculated ref. index. Attached is the code.
He didn't seem to have implemented the formulae as he should've. But he claimed he had various other samples measured and got the correct answer with this routine.
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Kas
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MatLab Code.txt ‏2 KB

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帖子被trinight在02-11-2006 07:51 PM时编辑过了
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LabVIEW Champion . Do more with less code and in less time .
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The problem may be encountered by anyone running a non-us LabView installation:
I am located in Norway, and over here we use the comma (,) as the separator in floating point numbers: So, the use 3.14 is written like 3,14.
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Message Edited by geirove on 06-13-2008 06:23 AM
Geir Ove

geirove wrote:
JoeLabView wrote:
Hi Geir,
It is not a bug.  ............
The node does not recognize localized decimal separators."
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Failing to do so may cause serious, expensive and very hard to trace errors.
Sorry, but I would expect that the NI team in their 20. year of LabView development is capable of better than this.
Sorry to disappoint you! It's not a bug since that statement is absolutely valid albeit useless in that context.
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And the NI team really is a lot better than you think. The online help may be a bit short about the reasons why the comma is not supported as decimal point but there have been many people thinking about this before it was made like that. It was either C syntax support without localized decimal point or some homegrown syntax with localized decimal point and they went for the first.
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a division of Test & Measurement Solutions

How to use matlab program in formula node in labview?

hi,
i've got one equation of voltage regulation. so i did create program for that in matlab.and want to use it in formula node in labview.but i don't know how to do that.can someone please help me for that?
regards
bhavin

If you have already written Matlab code it is easier to import it straight into a Mathscript node. If you use a Formula node you need to translate m- syntax to c-syntax which may take longer. Note that the Mathscript node
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These structures can be on the block diagram under Programming>> Structures.
KostasB
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Message Edited by KostasB on 05-28-2008 08:39 AM
Attachments:
mathscript-form node1.PNG ‏8 KB

Applying delay in formula node in labview

hi every bod
Solved!
Go to Solution.

If you have not done so yet, please go through the free on-line tutorials about LabVIEW.
Rarely is the formula node the most appropriate way to write code in LV. The native LV constructs may be a bit awkward at first for someone with a text-based programming background. Once you learn to use dataflow and to recognize the functions by their icons, you may find that graphical programming can be both powerful and easy to read.
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Lynn

Formula in LabVIEW

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