How can I find the last element amongst a set of grouping variables?

I have a 150x2 matrix in which the first column contains numbers that can be considered 'grouping variables' and the second column contains values associated with those grouping variables. So a small 12x2 version would look like this

 200741  5441
 200741  5524
 200741  5428
 200742  5670
 200742  5668
 200742  5559
 200742  5215
 200743  5184
 200743  5473
 200743  5496
 200743  5568
 200743  5702

I'd like to find the last value of the values associated with each grouping variable. So the above example would yield a last element of 5428(for variable 200741), last element of 5215(for variable 200742) & last element of 5702(for grouping variable 200743). After I find the unique vales of grouping variables in coumn1, how do I take the last element in column2 corresponding to each grouping variable?

Answer 1

[dpb]

ix=[find(diff(x(:,1));length(x)];  % index of breakpoints plus last 
subset=x(ix,:);                    % the selected points