How to transform a matrix to a binary type in Matlab?

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Matrix A is as follows:
A = [0 240 245 250
25 1 2 1
63 3 2 1];
First row is header of the matrix.
Except column1 that is unique id, there are 3 different variables in the matrix. I want matrix A transformed to the binary matrix, like the following matrix:
B = [
0,240,240,250
25,1,0,1
25,0,1,0
25,0,0,0
63,0,0,1
63,0,1,0
63,1,0,0];
Id 25 and 63 repeated 3 times, because there are 3 types of variables. For example, first row: 1,0,1 represents that there was type 1 in the matrix A(2,2) and no type 1 in A(2,3) and 1 in A(2,4).
  2 Comments
James Tursa
James Tursa on 25 Feb 2016
In your example, the "25" rows are ordered by the types 1, 2, 3. But in the "63" rows, they are ordered by the types 3, 2, 1. Is this how you really want it? I.e., you don't want it always ordered by 1, 2,3, but you want the output ordered by how the arrangement is in A?
Moe
Moe on 25 Feb 2016
Thanks James,
I want it always ordered by 1, 2,3.

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Accepted Answer

James Tursa
James Tursa on 25 Feb 2016
Edited: James Tursa on 25 Feb 2016
E.g., using a loop:
[m,n] = size(A);
n1 = n - 1;
B = zeros((m-1)*n1+1,n);
B(1,:) = A(1,:);
for k=2:m
kx = (k-2)*n1 + 2;
B(kx:kx+n1-1,1) = A(k,1);
B(kx:kx+n1-1,2:n) = bsxfun(@eq,(1:n1)',A(k,2:n));
end
A little bit harder to follow, but without the loop:
[m,n] = size(A);
n1 = n - 1;
Adata = A(2:m,2:n);
Bcol1 = ones(n1,1)*A(2:m,1)';
Bdata = reshape(bsxfun(@eq,(1:n1)',Adata(:)'),[],n1);
B = [A(1,:); Bcol1(:) Bdata];
  3 Comments
Image Analyst
Image Analyst on 27 Feb 2016
I'm curious why you need this strange array. What do you want to do once you have it? There may be a more straightforward or simpler way of accomplishing that.
Moe
Moe on 29 Feb 2016
Hi Image Analyst,
I need to transform my raw matrix to binary (0,1), then I can use it for clustering. Does it make sense?

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