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Re: Compare two vectors and got indices of the identical numbers
Posted:
Feb 16, 2013 7:52 PM


On 2/16/2013 5:53 PM, Danny wrote: > How to compare 2 vectors and got the indices of 2 identical numbers > > lets say I have matrix a >>> a=[250;500;750;200;600;800;230;650;800] > > a = > > 250 > 500 > 750 > 200 > 600 > 800 > 230 > 650 > 800 > > and I sort matrix a to matrix b > >>> b=sort(a) > > b = > > 200 > 230 > 250 > 500 > 600 > 650 > 750 > 800 > 800 > > and I want to compare matrix b to matrix a to identify in which indices of matrix a is >equal to the content of matrix b. > > For example for the number 230 in matrix b is located in the indices of #7 in matrix a > or number 650 in matrix b is located in the indices of #8 in matrix a > > Thanks before for the answer > > Regards >
one way:
 a=[250;500;750;200;600;800;230;650;800]; b=sort(a,1); N=length(a); for i=1:N [~,N(i)]=ismember(b(i),a); end N 
4 7 1 2 5 8 3 9 9
Nasser



