uCalc Fast Math Parser for LabVIEW?

[Corbier]

Several customers have been using the uCalc math parser product with LabVIEW.  Recently one LabVIEW / uCalc user has attracted my attention to the fact that the new version of uCalc FMP is now harder to use with LabVIEW.  Direct support for LabVIEW was never figured into the design of uCalc.  It just so happened that the older uCalc version worked with it.  Now, I’d like to figure out if there are enough potential uCalc FMP users to make it worth adding direct support for LabVIEW.

uCalc FMP lets you evaluate math expressions that are defined at runtime.  You can define functions, operators, and variables, and use them in your formulas.  The older version that is easier to use with LabVIEW can be found at www.ucalc.com/mathparser/ucfmp20.zip (you won’t find the old version in the current download page for now).

I myself have no experience with LabVIEW.  However, with some 3rd party help, the user who contacted me recently was able to interface the new uCalc version with LabVIEW.  Perhaps LabVIEW developers may want to weigh in.  Might you be able to create an “official” uCalc FMP wrapper for the current version of uCalc, or give some tips on what it would take for me to do it?

[altenbach]

Sorry, I am not familiar with ucalc, but this sounds interesting. Do you have any more details how people were using it in the past and what the new problems are?

Newer versions of LabVIEW have an "import shared library" (menu...tools...import shared library (.dll)...) , that, given a dll, a header file and other info, will create a set of VIs that can be used directly in LabVIEW. I think it would be sufficient to ensure that your distribution contains enough information so this works without mayor problems. 🙂

(If you don't have LabVIEW and want to try for yourself, you can download an evaluation version)

Maybe somebody with a bit more experience with all this can provide more detail.

[Corbier]

In the previous DLL, I exported a series of functions such as an eval routine that returns the result of evaluating an expression, as in

ucEval("5+4")

which would return 9; a routine to define functions as in

ucDefineFunction("Area(length, width) = length * width")

or variables as in

ucDefineVariable("MyVar = 123") 

plus a list of other routines.

The new version was completely redesigned.  You can do a lot more.  However, one exported function named uCalc() encapsulates most of the component's functionality.  Instead of exporting many routines from the DLL, wrappers for routines like ucEval, ucDefineFunction, ucParse, etc., are defined in include files for the supported compilers.  On the surface, things run roughly the same for the supported compilers, despite the changes under the hood.  But apparently not so for LabVIEW.

ucDefineVariable for instance, which previously was directly exported from the uCalc DLL is now defined as follows in the include file for Visual Basic (classic):

Public Function ucDefineVariable(Definition As String, Optional ItemAddress As Long = 0, Optional ByVal t As Long = 0) As Long
   Dim ItemDef$
   ItemDef$ = "Var: " + Definition
   If ItemAddress Then ItemDef$ = ItemDef$ + " At " + Str$(ItemAddress)
   ucDefineVariable = uCalc(uc_Define, ItemDef$, 0, 0, 0, t)
End Function

By the way, what is the link to download the evaluation version of LabVIEW?  I found links for the tutorial.  And there's a "Test-Drive LabView" link that brings me to an online evaluation version.

[altenbach]

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@Corbier wrote:

By the way, what is the link to download the evaluation version of LabVIEW?  I found links for the tutorial.  And there's a "Test-Drive LabView" link that brings me to an online evaluation version.

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If you can get your hands on a newer LabVIEW CD or DVD, you can just install it without license number and it will be in evaluation mode. I could not find a download for 8.5, but the 8.2 version is at the following link:

ftp://ftp.ni.com/evaluation/labview/pc/labview_82.exe

[Corbier]

Thanks for the link.  Greatly appreciated!

[Corbier]

Wow! Is the LabVIEW evaluation file really 500+ MB?  I started downloading.  But after 1 MB, there were 3+ hours left for the download.  Maybe I'll try the online version.

[Corbier]

I have now created a special wrapper DLL, which I hope will allow you to use LabVIEW with the current version of uCalc FMP (version 2.91).  Since I have no experience with LabVIEW myself, I will need the help of LabVIEW users to make sure this works just right.  Please visit:

www.ucalc.com/ubb/Forum8/HTML/000021.html

and download the uCalc wrapper DLL for LabVIEW.  Then go to the uCalc FMP download page at:

www.ucalc.com/download.html

to download the current version of uCalc FMP.

[altenbach]

Great! Thanks. I'll check it out, probably over the weekend. 🙂

[Corbier]

Have you had a chance to check it out during the past week?  What did you think of it?

[Corbier]

A few months after that last post, a newer version of uCalc Fast Math Parser was released (in December) with better support for LabVIEW, thanks to the help of a LabVIEW user.  Please check out version 2.95 of uCalc FMP.  I'd like to hear more from LabVIEW users who have tried it with uCalc.