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## Re: newbie question: assigment to N-d arrays returns strange values

 From: Henry F. Mollet Subject: Re: newbie question: assigment to N-d arrays returns strange values Date: Sat, 06 Aug 2005 11:55:14 -0700 User-agent: Microsoft-Entourage/11.1.0.040913

```If m=zeros(3, 2, 2);
Then what does m(3,:) mean?
I understand m(3,:,:):
octave:14> m(3,:,:)
ans =
ans(:,:,1) =
0  0
ans(:,:,2) =
0  0
Henry

on 8/5/05 11:31 PM, Amir Seginer at address@hidden wrote:

> Hello,
>
> This might be a known problem, but I couldn't find any reference to it.
> When assigning to an n-dimensional array (see below) I get results which
> are different from Matlab. Also, in one case I get some strange values
> in the array as well.
>
> I wrote the the following code in Octave (using --traditional):
>
>>>  m=zeros(3, 2, 2) ;
>>>  a= [1 2 3 4] ;
>>> m(3, :) = a
> m =
>
> ans(:,:,1) =
>
>          0        0
>          0        0
>          1        2
>
> ans(:,:,2) =
>
>          0        0
>          0        0
>          0        0
>
> which is not what I expected (3 and 4 were not assigned). Even worse,
> when I did
>
>>> m=zeros(3, 2, 2) ;
>>> a= [ 1; 2; 3; 4] ;
>>> m(3, :) = a
> m =
>
> ans(:,:,1) =
>
>          0        0
>          0        0
>          1        2
>
> ans(:,:,2) =
>
>    0.0e+00  *
>
>        NaN      NaN
>        NaN      Inf
>        NaN      Inf
>
> This gives strange values on the 2nd "page". Further more, in normal
> mode the same code gave
>
> octave:8> m=zeros(3, 2, 2) ;
> octave:9> a= [ 1; 2; 3; 4] ;
> octave:10> m(3, :) = a
> m =
>
> ans(:,:,1) =
>
>    0  0
>    0  0
>    1  2
>
> ans(:,:,2) =
>
>      0.0000e+00   5.1715e-319
>     1.1116e-321    0.0000e+00
>      0.0000e+00    0.0000e+00
>
> Is there a way to overcome this, or at least get an error/warning. I'm
> using octave-2.1.71
>
> Thanks,
>
> Amir.
>
>
>
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