[Pkg-octave-devel] [OctDev] A Bug in Octave-OdePkg
Wang Long
mr.wang.long at gmail.com
Fri Oct 10 02:49:28 UTC 2008
On Wed, 2008-10-08 at 21:33 +0200, Thomas Treichl wrote:
> Wang Long schrieb:
> > Hi Thomas,
> >
> > Thank you very much in helping me with this problem! The solution in
> > your email solved the problem I mentioned before, but when I tried some
> > other t_in's, for example,
> > t_in_2=[0.00 0.10 0.23 0.38 0.63 1.21 1.97];
> > t_in_3=[0.00 0.03 0.05 0.11 0.17 0.25 0.38 0.47 0.68 0.91 1.38 1.98];
> > it seems that the same problem comes out again in the 0.6.0 release of
> > odepkg :(
> >
> > I examined the improper t_out's, and found that every element in them is
> > identical to t_in's, respectively, except those at ``t_out(end-1)'',
> > which is created by ode45. Therefore, can we simply make ode45 check the
> > length of t_out, and delete certain elements of t_out (and ``y'', of
> > course) if the length of t_out is larger than t_in?
> >
> > Thanks!
> >
> > Regards,
> > Wang Long
>
> Hi Wang,
>
> there seems to be another problem in the 0.6.0 solver file(s), I can't see that
> with the current sources. I'll send you a snapshot of the latest solver files
> offside this mailing list in a few minutes (because of the sizes of these
> files). Please try once again with these files...
>
> Thomas
Hi Thomas,
The problem was solved by the snapshot of latest version, thank you very
much!
At first, your latest snapshot of ode45, ode78 and other ode-solvers
does not work at all but complained:
error: structure has no member `OutputSave'
error: evaluating argument list element number 1
error: if: error evaluating conditional expression
error: evaluating if command near line 166, column 3
error: called from `ode45' in file `ode45.m'
I think this is due to the mismatch between `odeset' version 0.6.0 and
the latest snapshot. Then I downloaded the latest version (0.6.4) of
odepkg released at http://octave.sf.net/odepkg/ and tried with my
t_in's, only got another error:
Solving has not been successful. The iterative integration
loop exited at time t = 1.470000 before endpoint at
tend = 1.780000 was reached. This may happen if the
stepsize grows smaller than defined in vminstepsize. Try
to reduce the value of "InitialStep" and/or "MaxStep" with
the command "odeset".
Fortunately, everything works after the ode45 and other ode-solvers in
odepkg version 0.6.4 were overwritten with your latest version. Thank
you for your continuously help!
Best wishes and regards!
Wang Long
More information about the Pkg-octave-devel
mailing list