Re: why two indexes in 1d cell array ? (octave-3.4.2) ... how about more dimensions ?

[Sergei Steshenko]

--- On Wed, 8/10/11, Ben Abbott <address@hidden> wrote:

> From: Ben Abbott <address@hidden>
> Subject: Re: why two indexes in 1d cell array ? (octave-3.4.2) ... how about 
> more dimensions ?
> To: "Sergei Steshenko" <address@hidden>
> Cc: address@hidden
> Date: Wednesday, August 10, 2011, 2:06 PM
> On Aug 10, 2011, at 3:18 PM, Sergei
> Steshenko wrote:
> 
> > c =
> > {
> >  [1,1] = a string
> >  [1,2] =
> > "
> > 
> > I see _two_ indexes, i.e. "[1,1]...", "[1,2]", though
> to me it looks like
> > created a _1d_ (just _one_ dimension) cell array;
> 
> Matlab originated from Fortran code. Thus, arrays were/are
> column-major.
> 
>     http://en.wikipedia.org/wiki/Row-major_order#Column-major_order
> 
> When the source code switched to C, Matlab maintained the
> default column-major storage order for arrays. This means
> that A = 1:5 produces a single row with 5 columns.
> 
> However, since C is row-major ...
> 
>     http://en.wikipedia.org/wiki/Row-major_order#Row-major_order
> 
> ... a 1D array requires two indices. The fist specifies the
> row [1], and the second the column.
> 
> For compatibility with Matlab, Octave adopted the same
> approach.
> 
> > Is this all expected and documented behavior ?
> 
> Yes this is expected and deliberate. If you search the
> manual. you'll find a few instances where the effect of
> "column-major" ordering is mentioned.
> 
> Ben
> 

You have (conveniently) omitted my example with 'celldisp':

"
octave:1> c = {"a string", rand(2, 2)}
c =
{
  [1,1] = a string
  [1,2] =

     0.245929   0.096505
     0.018941   0.231544

}
...
octave:4> celldisp(c)
c{1} =

a string

c{2} =

   0.245929   0.096505
   0.018941   0.231544

octave:5>   
".

The 'celldisp' example has just _one_ index. And I'm happy with it.

Why/what for in practice should I see _two_ indexes in 1d cell arrays ?

I.e. if I only use 'celldisp' to display cell arrays contents, what
_practically_ important information about cell arrays am I going to lose ?

Thanks,
  Sergei.