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Re: [femm] New beta version



David,
I would like to recommend a few minor changes to FEMM that will help
speed up simulation setup, and analysis. These are simple changes that
can have a big impact.
1. Do not reset the grid size when reloading or opening new files. I would like
to set it and have it remain at what I set it to from then on.
2. Set the default to "snap grid" when first starting up the simulator or
femmview.
I have no occasion to NOT use snap-to-grid when I am drawing shapes or
drawing line integral contours.
3. Do not reset the window size when reloading or opening new files. If I have
set
it to full screen I want it to stay that way.
4. Couple the + and - zoom screen buttons to the numeric keypad + and - as hot
keys and also the arrow keys to the on screen arrows for hot key panning.
5. In FEMM view allow interrupt of panning or zooming so we can zoom in quickly
to set up line integral contours fast without having to wait for the screen
redraw to
finish. This would be very helpful for larger simulations. Interrupt can be
esc or
just click the arrow button or press the arrow key to stop redraw and
increment
to the new position.

I hope these are helpful suggestions. These are things I have noted in other
professional
tools in the past. I have done some similar programming myself and these should be
fairly easy
to implement. I would recommend putting them in the new beta version for the
second
beta test.

Regards,
Dave Squires

dcm3c@xxxxxxx wrote:

> All--
>
> I've put up a new beta version of femm 3.0 in the "files" section of the
> mailing list website at:
> http://groups.yahoo.com/group/femm/files/
> I'd be interested in feedback/bug reports, especially with respect to the new
> functionality that has been implemented.
>
> The most significant change to this version is the addition of periodic and
> antiperiodic boundary conditions. This was sort of the last "big" feature
> that I wanted to put into the 3.0 version before making it a "release" rather
> than a "beta." One uses this sort of boundary condition by choosing
> "Periodic" or "Antiperiodic" in the "BC Types" drop list in the boundary
> property dialog. Each defined periodic boundary condition should be applied
> to two and only two segments or arc segments that are meant to be connected
> periodically. If there are multiple pairs of segments or arcs, you have to
> define multiple boundary conditions.
>
> Anyhow, I have also posted a zip file containing two examples that employ
> periodic and antiperiodic boundary conditions. One sample is the switched
> reluctance motor pictured at:
> http://www.elec.gla.ac.uk/groups/speed/software/feashot.html
> Just as on this web page, periodic boundary conditions have been applied so
> that only part of the motor need be modeled.
> The second example I have taken from the paper,
> Lowther, D.A., Freeman, E.M., and Forghani, B., "A sparse matrix open
> boundary method for finite element analysis," IEEE Transactions on Magnetics
> , 25(4):2810-2812, July 1989.
> This is an example of a pretty slick way that one can go about modeling open
> boundary problems through the use of periodic boundary conditions. There are
> also a couple of other interesting papers in Trans. Mag. by the Infolytica
> guys that explore other aspects of this open boundary approach.
>
> Anyhow, I the implementation of the periodic and antiperiodic boundary
> conditions seems to run ok, but there could be bugs that pop up due to other
> people testing it in ways that I might not have considered. It turned out
> that there were a lot more subtleties in implementing these boundary
> conditions than one might think, so there is certainly the possibility of
> bugs. One thing that is different about these bcs (but not a bug) is that
> triangle gets called twice during the meshing of problems with pbcs and apbcs.
>
> I also modified the program so that it looks at a file called "colors.dat"
> that lives in the femm30\bin directory for definitions of the colors used in
> the various modules of femm. A femm user who is colorblind turned me on to
> the necessity of being able to modify the color scheme that femm uses. And
> it seems like nobody but me likes the mesh rendered in yellow.... Anyhow,
> this is a text file, and you change around the colors by editing it with
> notepad or whatever.
>
> This version also has a manual that has been partially updated to 3.0 from
> 2.1a, but there's still quite a bit of work left on the documentation.
>
> Dave Meeker
> --
> http://members.aol.com/dcm3c
>
>
>
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