Re: fsolve test failure

[Jaroslav Hajek]

On Thu, Jan 29, 2009 at 10:09 PM, John W. Eaton <address@hidden> wrote:
> On 29-Jan-2009, Jaroslav Hajek wrote:
>
> | So, you're voting for choice 2? Make just optimget queries to be case
> | insensitive? I'm a little confused now.
>
> No, they both need to be case insensitive.  So all of
>
>  optimset ('tolx', ...)
>  optimset ('TolX', ...)
>  optimset ('TOLX', ...)
>
> should work and set the same internal variable.  Similarly, all of
>
>  optimget (opts, 'tolx')
>  optimget (opts, 'TolX')
>  optimget (opts, 'TOLX')
>
> should work and retrieve the same internal variable value.  But a call
> like
>
>  x = optimset ();
>

This call returns an empty structure. What do you mean?

> should return a structure with the field 'TolX' (not 'tolx' or 'TOLX').
> Otherwise, code like I showed earlier will fail, because accessing
> structure fields directly is a case-sensitive operation.  And if there
> is nothing preventing users from doing
>
>  opts = optimset ();
>  opts.TolX = foobar;
>
>  fsolve (..., opts);
>
> then I'm sure they will do it.  So we might as well allow this now
> while we are thinking about it rather than wait for a bug report.
>

If you want to allow this, then I see no other way than make optimget
do a case-insensitive lookup of the fields. In that case, it is
irrelevant what case will optimset use.

> jwe
>



-- 
RNDr. Jaroslav Hajek
computing expert
Aeronautical Research and Test Institute (VZLU)
Prague, Czech Republic
url: www.highegg.matfyz.cz