Logicals with empty double column vectors

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BdS
BdS le 25 Avr 2019
Commenté : Jan le 25 Avr 2019
Hi
I have got this code:
a=Pf_ID; %--> 5x1cell
b=magic(5);
c=find(cellfun(@isempty,a)); %--> creates a double row vector with two entries as 2 elements in Pf_ID as empty
b(:,c)=[];
a(c,:)=[];
cc=find(cellfun(@isempty,a));
ccc=double.empty(0,1);
if cc==ccc % -->QUESTION: I cannot manage that this if statement becomes 'true' so that a=88. Do you have any hints?
a=88
end
  1 commentaire
Jan
Jan le 25 Avr 2019
The question is not clear:
I cannot manage that this if statement becomes 'true' so that a=88.
What do you get? What do you want instead? What exactly does "double.empty(0,1)"? Maybe you mean:
if isempty(cc)
a = 88;
end

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Guillaume
Guillaume le 25 Avr 2019
c=find(cellfun(@isempty,a));
a(c,:)=[];
The second line implies that a is 2D. Yet, find as used will return linear indices, so if a is indeed 2D the second line will error with 'index exceeds array dimension' if any element in column 2 or later is empty. You haven't explained what this code is meant to do but probably doesn't do what you want. It certainly doesn't do it safely.
You also haven't explained what your 2nd bit of code is meant to do. If you want to test that cc is empty, you use the exact same isempty test you've been using:
cc = find(cellfun(@isempty, a))
if isempty(cc)
a = 88;
end
Or you don't bother with the find, and just check that there's no true value returned by your cellfun:
if ~any(cellfun(@isempty, a))
a = 88;
end
  1 commentaire
Jan
Jan le 25 Avr 2019
As usual I mention, that cellfun('isempty', C) is more efficient than cellfun(@isempty, C).

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