How do I sort the rows in one array based on the row order of another array?

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I have 2 matrices;
C is 7 x 3 double and G is a 9 x 3 double;
C = [1 1 0; 1 0 1; 0 1 1; 1 0 0; 0 1 0; 0 0 1; 0 0 0];
G = [0 1 1; 0 0 0; 1 0 0; 1 0 1; 0 0 1; 0 0 0; 0 1 1; 1 0 0; 1 0 0];
I’m attempting to create a subset of C (New_C), based on the contents of G, where the order of the rows appearing in New_C are identical to those in C. The proper output would be as follows;
New_C = [ 1 0 1; 0 1 1; 1 0 0; 0 0 1; 0 0 0];
I am able to attain the unique rows in G with the following;
New_C = unique(G, ‘rows’);
But the rows are not in their proper order.
Is there a way to re-order/sort the rows in New_C such that their order matches the rows in C ?
Thanks you.

Accepted Answer

James Tursa
James Tursa on 9 Nov 2015
Try this (Caution, untested since I am not on a machine with MATLAB at the moment):
[~,Locb] = ismember(New_C,C,'rows');
New_C = C(sort(Locb),:);
Assumes all rows of New_C can be found in C.
  1 Comment
Brad
Brad on 10 Nov 2015
James, thanks for the push!
I had to make a mod and add some code, but it works:
% Find the subset of C
[~,Locb] = ismember(G,C,'rows');
New_C = C(sort(Locb),:);
% Get the unique values and sort
[~,idx]=unique(New_C,'rows');
out=New_C(sort(idx),:);

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