MATLAB: Alternating equations every other row

subtraction

I have A= [3 2 1, 3 8 2, 3 9 2, 9 5 1, 3 8 3, 7 4 2]

For the first row I would like to subtraction Column 2 from Column 1, then for row I want to subtract Column 1 from Column 2. I want these two equations to alternate when going through the rows. In the end I want something that looks like this:

B= [1, 5, -6, -4, -5, 3]

Thanks!

Best Answer

B = diff(A(:,[1,2]),1,2).*(-1).^(1:size(A,1))'

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MATLAB: Delete duplicated row in a matrix

   I = ~ismember(a(:,1:2),b(:,1:2),'rows');
   a = a(I,:)

MATLAB: Matrix Manipulation

A = [1; 1; 3; 1; 2; 1; 1; 1; 3; 1; 1; 1; 1; 2; 1; 1; 1; 1; 1; 3; 1; 1; 1; 2; 1; 1; 1; 1; 1; 2; 2; 1; 1; 1; 2; 1; 1; 2; 1; 1; 1; 1; 1; 1; 3; 1; 1; 3; 2; 1; 1; 1; 1; 1; 1; 1; 2; 2; 4; 1; 1; 2; 1; 1; 1; 1; 2; 2; 1; 1; 1; 3];
a1=find(A==2)-1; %find the index of the 2
a2=find(A==3)-1; %find the index of the 3
a2=repmat(a2,2,1) %duplicate the 3 indexes
B=sort([a1;a2])'; %join and sort the solution, also transpose
%I transposed B because of your B example

Best Answer

Related Solutions

MATLAB: Delete duplicated row in a matrix

MATLAB: Matrix Manipulation

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