Re: [femm] Re: Batch processing / interfacing

[David Meeker <dmeeker@xxxxxxxxxxxxxxxxx>]

frank.e.lenning@xxxxxxxxxx wrote:

> This is fantastic. I now have a batch processor working thanks to
> Dave's open source policy. I wrote it in VBA and it took me about 12
> hours or so to get it fully functional. All the program does to get
> out currents in a block as a function of frequency is:
>
> 1) read in .fem file created using Dave's GUI. You must run the
> model once so you can use it "standalone" later.

Yes, the preprocessor has to do some "pre-meshing" and call triangle to mesh
the problem. Then, as long as the geometry doesn't change like in your case,
you can re-use the mesh.

>
> 2) edit the file to change the frequency - I do this using Word
> inside VBA.
> 3) launch FKERN using VB's Shell command. I haven't figured out yet
> how to detect if fkn is done so I have a timer that waits for a
> certain number of seconds before proceeding.

In Visual C++, if you start up a program with the CreateProcess command,
there is a function called WaitForSingleObject that you can use to figure out
when it is finished. Although I'm not a VB programmer, it appears that it is
possible to do the same thing in VB--I found a description on the web at
http://benjaminsoftware.hypermart.net/vbtips.htm.

>
> 4) read in the .ans file - I had to study this for a while to figure
> out the format but, again thanks to Dave's human readable file
> approach, that didn't take too long. I do the reading using Excel
> within VBA.
> 5) calculate block currents - this is where the open source really
> came in handy - I just studied Dave's femmeview cpp files long enough
> to figure out how he was calculating currents and duplicated it in
> VBA.
> 6) write the currents to another file.
> 7) loop back to step 1
>
> This would all be alot easier I think with DDE. I just wanted to
> give Dave a feel of how one user was attempting to batch process.
> Since the runs I do tend to be ~1/2 hour or so, the programming time
> was acceptable.
>
> Although I really don't know much about it, I think DDE would keep
> versatility which I think is important in this case. I believe the
> GUI should be kept simple and user friendly, at least until we really
> figure out the sort of "looping" functionality is useable by enough
> users to justify programming it into the GUI. I think most of the
> people wanting to do batch processing are "power users" anyways who
> aren't completely scared aware by a little programming.
>
> I'll post my little batch processor once I'm a little more proud of
> it in case anyone is interested.

Yes, I'd be interested to check it out. I've set up the files section at
http://groups.yahoo.com/group/femm/files/ so that any member of the list can
upload. If anyone has examples or anything that they are interested in
contributing that would be too big to mail around as an attachment (i.e.
anything more than a few kilobytes), they can upload it to the files section.

Dave.


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