On 3/13/10, Dieter Kaiser <drdieterkaiser at web.de> wrote:
> I would like to suggest to replace the calls to a Lisp break in the
> routines of taylor with a call to TAY-ERR.
>
> With this change taylor will no longer give a Lisp error when an
> unhandled case occurs, but throws an error. A user gets a Maxima error.
> When called from limit the error is catched and limit continues its
> work.
>
> This is an example in the routine stronger-var?:
>
> (when (alike1 v1 v2) (break "stronger-var? called on equal vars"))
>
> This is a possible replacement:
>
> (when (alike1 v1 v2)
> (tay-err
> (intl:gettext "taylor: stronger-var? called on equal vars.")))
Dieter, thanks for working on this problem.
I agree that a Maxima error is preferable to a Lisp break.
However, i hope we can print a message which indicates the origin
of the problem more clearly to the user. Is (ALIKE1 V1 V2) the
consequence of some incorrect or unintended or unhandled input
on the part of the user? If so, we should try to state the error
message in terms that the user understands.
best,
Robert Dodier