Hi David,Well, the program tests to see there are any extrema between node points. If there are, it smooths the data and tries again. This forces the curve to be monotonically increasing (although not exactly going through the originally defined points). However, it is still not impossible to give a curve that it doesn't like. I've seen this happen sometimes with curves with a strong "initial permeability" region in which the curve is monotonically increasing, but in which there is an inflection point. Anyhow, I picked some different points on the same curve to make a "new" bh curve. I've attached the file in which I did this. It seems to converge OK now, with the modified curve. In the long run, there probably needs to be some "stiff" version of the Newton iteration that can adjust the step size if things aren't converging.
I have a problem with the attached file: no solution can be found.
This model tries to solve a highly saturated lamination.
Note that I have changed the material specifications adding some points up
to B=3.0T (that should be never reached).
As far as I know the points that I have added should give a smooth
monotonic function (verified in femmplot and in excel diagram)
In case the problem was spline interpolation, why not to add a lower degree
interpolation as an option? I had the same problem with the function "fit"
in gnucap and order=3 for interpolating functions. The problem disappeared
with order 1 or 2.
Sorry--sometimes I get busy with other things, and I'm not very good about responding.
Bye
P.S. did you see my message dated 29 January? I have seen no comment about
it
> 1- In the preprocessor in point insertion mode, it woud be nice that the
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