How can I check whether the strictly positive elements of each row of a matrix are equal?

How can I check whether the strictly positive elements of each row of a matrix are equal? E.g. if

A=[0 1 1 2; 0 1 0 1; 3 0 3 0]

I want

B=[0;1;1]

[José-Luis]

There are no negative values in your example.

[MRC]

Sorry, I meant strictly positive, I have edited the question

[Geoff Hayes]

Cris - is this a homework question? Please review http://www.mathworks.com/matlabcentral/answers/8626-how-do-i-get-help-on-homework-questions-on-matlab-answers.

Answer 1

[per isakson]

    arrayfun( @(jj) (length(unique(A(jj,(A(jj,:)>0)))) == 1),(1:size(A,1)) )

returns

    ans =
         0     1     1

Answer 2

[Sara]

B = zeros(size(A,1),1);
for i = 1:size(A,1)
   temp = A(i,:);
   temp = temp(temp>0);
   temp = unique(temp);
   if(length(temp) == 1)
      B(i) = 1;
   end
end

Answer 3

[dpb]

The "deadahead" solution...

isPos=false(size(A,1),1);
for i=1:size(A,1)
  isPos(i)=all(diff(A(i,A(i,:)>0))==0);
end

Vectorize at your leisure... :)

[MRC]

Can I avoid the loop?

[dpb]

Yes, w/ arrayfun. That was left as "exercise for the student" :)

As illustrated by Per; same idea with anonymous function. As also showed, any of a number of ways to check on the consistency of the values in a row is doable.