> As the function 'self.grid_search()' executes 'self.minimise()' this
> single change will cover both the grid search and minimisation. The
> function 'isnan()' currently non-existent but could be implemented as
> Gary previously mentioned by checking the hex bit pattern of NaN.
If isnan() is to be implimented in this way, then a similar isinf() is
by far the best way to go. float('inf') is platform dependent, and
certainly will not work under Windows (I think I'm right in saying
windows has no valid string representation of inf or nan that would work
in that context).
That one I didn't know about. I thought Python handled inf correctly
but checking the bit value should be easy. What about checking that
the value is less than 1e300 instead, as that is the arbitrary
starting point for the grid search?
> This avoids fpconst.py and the switch from Numeric to Numpy. The
> question is whether to use the RelaxErrors or set some warning? Would
> this be alleviated by Gary's proposal of saving the program state just
> prior to throwing the error? For example using the function
> 'self.save()' within 'generic_fns/state.py', printing the error
> message, then quitting.
Saving state as part of the exception handling is a nice idea, but has
its limitations. Because the error could be thrown before, during or
after some change to the program state, the state which is saved will be
undefined and possibly inconsistent. As such a saved state may be of
limited use to most users. It would be a very valuable tool for
debugging, though.
I suppose it will probably leave too many temporary files lying
around. relax tends to throw errors if you do the slightest thing
wrong.
> What do you think? I think I covered most of the issues. I've made a
> branch of the 1.2 line located at
> svn://svn.gna.org/svn/relax/branches/nan_catch_test which has all
> these changes. Feel free to play around and modify this branch.
I'll have a bit more of a look, but it seems like a good fix.
But does it resolve the issue of whether the program should throw an
error and terminate or throw a warning and continue?
Edward
Re: Proposed solution to bug #6503.