Re: [OctDev] Proposed changes to cell2mat and inclusion in Octave

[William P. Y. H. <wil...@gm...>]

Part of the discussion on octave-dev follows:

On 12/9/05, David Bateman <Dav...@mo...> wrote:
> William Poetra Yoga Hadisoeseno wrote:
>
> >On 12/9/05, David Bateman <Dav...@mo...> wrote:
> >
> >
> >>Again, why? Here is matlab's output
> >>
> >> >> C =3D {[1], [2, 3, 4; 6 7 8]; [5; 9],[10 11 12]}
> >> >> cell2mat(C)
> >>??? Error using =3D=3D> cat
> >>CAT arguments dimensions are not consistent.
> >>
> >>Error in =3D=3D> cell2mat at 92
> >>        m{n} =3D cat(2,c{n,:});
> >>
> >>The error message seems to indicate that matlab just lets cat generate
> >>the error as well.
> >>
> >>
> >>
> >
> >Well, in that case then we should just let cat do the job ;)
> >
> >
> >
> >>Matlab doesn't respect their own documentation either
> >>
> >> >> C =3D {[1, 2], [3, 4]; [5; 9],[6 7 8; 10 11 12]};
> >> >> cell2mat(C)
> >>
> >>ans =3D
> >>
> >>     1     2     3     4
> >>     5     6     7     8
> >>     9    10    11    12
> >>
> >>This is with R14sp2..
> >>
> >>
> >>
> >
> >OK, this is consistent with the old (current) cell2mat.
> >
> >
> >
> >> >> C =3D {[1;2],ones(2,2)=3D=3D1}
> >>
> >>C =3D
> >>
> >>    [2x1 double]    [2x2 logical]
> >>
> >> >> cell2mat(C)
> >>??? Error using =3D=3D> cell2mat
> >>All contents of the input cell array must be of the same data type.
> >>
> >>However, this seems stupid to me, as logical arrays are supposed to be
> >>promoted to double in normal usage... I'd prefer that the above remaine=
d
> >>legal..
> >>
> >>
> >>
> >
> >Yes, I also think the above should work (logical -> numeric). Also, I
> >think char arrays should be allowed (using ascii). What do you think?
> >
> >
> >
> Promotion of type is implicit in the concatenation operation. If cat
> allows it so should cell2mat in my opinion. Therefore just letting cat
> generate the error messages for an illegal concatenation of types makes
> sense to me, as it will report the two offending types in the
> concatenation operation. I believe this means that cell2mat needs no
> changes...
>
> Regards
> David
>
>
> --
> David Bateman                                Dav...@mo...
> Motorola Labs - Paris                        +33 1 69 35 48 04 (Ph)
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>
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>

It seems that no one has objections at this point, so I'm braving
myself to submit this file (imported from octave-forge). The file is
attached.

--
William Poetra Yoga Hadisoeseno