Possible bug in the assignment operator when handling arrays of structs which hold arrays of structs (or I just don't know how to correctly phrase the search on the bugs list)

[Brendan Drew]

I'm afraid this is a bit involved, but I figured it's better to ask and 
see if this has already been addressed before reporting it as a bug.

I have a structure, called a feature. Features hold several different 
histograms (plain old matrices).

I have a structure called a state, which is described by a feature and 
some book keeping data.

I have a structure called a SSM which holds a vector of states and some 
book keeping data.

I have a matrix of SSM structures.

What I would /really/ like to do is something like this:

for i=1:r
 for j=1:c
    ssm(i,j) = UpdateSSM(ssm(i,j), newImageChunk(i,j));
 end;
end;

I can't do that (octave complains about a mismatch of struct field names 
when I do the assignment). So I do this instead:

for i=1:r
 for j=1:c
   temp = UpdateSSM(ssm(i,j), newImageChunk(i,j));
   ssm(i,j).states = temp.states; % <--- This is the assignment that 
doesn't do what I expect it to
 end;
end;

ssm(i,j).states is an array of states as described above.

Any thoughts on what is going wrong?  I've checked the return value, and 
it is definitely correct. I've tried a couple things to get the code to 
work:

for i=1:r
 for j=1:c
   temp = UpdateSSM(ssm(i,j), newImageChunk(i,j));

   n = length(temp.states);

   for k=1:n
     ssm(i,j).states(k) = temp.states(k); % <--- also doesn't work
   end;
 end;
end;

I also tried:

for i=1:r
 for j=1:c
   temp = UpdateSSM(ssm(i,j), newImageChunk(i,j));

   n = length(temp.states);

   for k=1:n
     ssm(i,j).states(k).descriptor.gray = temp.states(k).descriptor.gray;
     % gray is a gray scale histogram, descriptor is a feature as 
described
     % above

     % Copy the remaining histograms stored in descriptor
   end;
 end;
end;

I even went so far as to attempt to copy each histogram element by 
element. This (also) didn't work. Any thoughts?

Thanks much,

Brendan.

--
Brendan Drew
Research Scientist
PercepTek, Inc.
12395 North Mead Way
Littleton, CO 80125
Tel: 720-344-1037 x 126
Fax: 720-344-2360



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