Upgrading to MATLAB 6.1 breaks LabView interface

[chrisdaft]

I had a LabView 6 application which worked fine using MATLAB 6.0 (R12). I upgraded MATLAB to 6.1 (which changes the installation directory) and now LabView cannot start MATLAB. I reinstalled LabView, but that didn't help.

What's up?

Thanks,
Chris Daft

[Gorka Larrea]

How did you call Matlab? If this is done using ActiveX, you can try rearranging automation open and property and invoke nodes, ActiveX calls can change from one to another version of a program, see Office 97 and 2000. If you are not using ActiveX... well this could be the same problem...
Good luck

[chrisdaft]

Hi Gorka,

Thanks for your posting. This is Labview 6.0.2 under Win2k, by the way. MATLAB is being called implicitly [I am not writing any code that starts it up], and I am not sure if it uses COM or ActiveX or DDE or some other mechanism. If I create a VI with a one-line MATLAB script in it and look at the error output, Labview says "Error occured while executing script. Error message from server: . in Untitled.vi" (Untitled.vi is my instrument.)

When MATLAB came out with its last major release, there was no interface problem with the Labview code. It's odd that 6.0 -> 6.1 is causing trouble.

Chris

[ksf]

Dear Chris,

I am experiencing exactly the same pain as you in my attempts to run Matlab(6.1) scripts from Labview(6i). Have you managed to find a solution?

Kind regards

Kevin

[chrisdaft]

Hi Kevin,

I am pestering both MathWorks technical support and National technical support. MathWorks claims there is no change to the ActiveX interface of MATLAB going from 6.0 to 6.1. But thanks very much for posting this message. It gives my whining more weight since it becomes harder to claim my machine is mis-configured...

Chris

[chrisdaft]

Hi Kevin,

To quote from tech support,

"R&D has investigated the problem and found that MathWorks changed the
ActiveX ID of MATLAB with version 6.1."

What you need is an altered matscript.dll - as far as I can tell this nails the problem. You can get that from Darren Nattinger at National Instruments (not sure the licensing would allow to send you this).

Cheers,
Chris

[uwaj]

I am facing the same problem trying to get Labview to invoke MATLAB 6.1

Could you give me some info how I could contact Darren at NI / who else could I contact?

Thanks,
Ajay

[Toby]

Hi,

did you find out where to get the updated dll? When you said, labview could not invoke matlab 6.1, did you still have matlab 6.0 installed?

On my NT system I have both ML 6.0 and ML 6.1 installed and labview just loads ML 6.0. On the other hand on my Win2000 labtop, only ML 6.1 is installed and there the script does not work.

Thanks,
Toby.

[Darren]

Hello all,

For the complete description of this problem and its solution, please read the KnowledgeBase article entitled "LabVIEW Does Not Interface Properly with MATLAB 6.1". It explains the cause of the problem, and gives an updated DLL that corrects it.

Have a pleasant day,
Darren N.
NI Applications Engineer