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something akin to singleton expansion in object array assignment

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Val Schmidt
Val Schmidt on 9 Dec 2013
Hello, I'm writing to inquire if anyone knows if it's possible to create an object array and to assign a single field many values all at once - sort of like A(1:5) = ones(1,5);. For example.
classdef bug
properties
legs
end
end
for i=1:5
bugs(i) = bug();
end
% This doesn't work.
bugs(1:5).legs = [6 6 8 8 4];
% This doesn't either
bugs.legs = [6 6 8 8 4];
% Or this
bugs.legs = 6
Does one have to write a loop or maybe modify subsasgn (ugh). It seems like all other functionality available to other matlab objects is available with the built in subsasgn but this one.
Thanks in advance,
Val

Answers (2)

Walter Roberson
Walter Roberson on 9 Dec 2013
Singleton expansion does not use that syntax for regular objects. Experiment with
L = num2cell([6 6 8 8 4]);
bugs(1:5).legs = L{:};
  2 Comments
Walter Roberson
Walter Roberson on 9 Dec 2013
You could try
b = num2cell(ones(1,5));
a(1:5).legs = deal(b{:});
or
[a(1:5).legs] = deal(b{:});
deal() should not be necessary anymore, but it was around R2007a-ish that that changed.

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per isakson
per isakson on 9 Dec 2013
Edited: per isakson on 9 Dec 2013
Or hide the num2cell in a function
>> [bugs.legs] = num2list( [12 13 14 8 4] )
bugs =
1x5 bug array with properties:
legs
where
function varargout = num2list( num_vec )
% num2list
varargout = num2cell( num_vec );
end
  3 Comments
Alfonso Nieto-Castanon
Alfonso Nieto-Castanon on 10 Dec 2013
Or even: (also without the checks)
% num2list
function varargout = num2list(varargout)
end

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