PLEASE HELP ME find coresponding column indexes.

I have a matrix V of size (3x3) and another matrix W (3x3), where off-diagonals are zero in matrix W and diagonals are non-zero. Then I have A=sort(diag(W)). Now I want to get the corresponding column index number from matrix W.

CODE IS GIVEN BELOW:

V= [3 4 5; 4 7 8;2 6 1];
W=[5 0 0;0 7 0;0 0 2];
A=sort(diag(W));
A =
   2
   5
   7

Now i want the corresponding column index number. for example: in this problem first element is 2 and corresponding column index number 3 from matrix W. Similarly for 5 is 1 and for 7 is 2 respectively.

[Star Strider]

‘Now i want to get the corresponding column index number from matrix W.’

Corresponding to what?

[Stephen23]

Please edit your question.

• Format the code so that it is readable (use the {} Code button above the text box)
• Describe the problem in more detail (as Star Strider has already pointed out)
• Don't put three sentences in the title.
• Read this:

http://www.mathworks.com/matlabcentral/answers/6200-tutorial-how-to-ask-a-question-on-answers-and-get-a-fast-answer

[palash de]

corresponding to sorted elemnt

[Image Analyst]

Do you mean the rows and columns of V that correspond to values in A? Is so, why even bother to sort W? And what if the numbers in W don't appear in V? read this

[Stephen23]

Interestingly you don't refer to matrix V at all. Is this intentional?

Answer 1

[Stephen23]

If you read the documentation for the sort function, you will find that there is a second output giving the indices of the sort. Your code would become:

[A,I] = sort(W)

Try that, and it might be useful for solving your problem.

[Star Strider]

True enough, but sorting a diagonal matrix ... ?

[Stephen23]

Yes, the whole thing is a bit fishy... hopefully the OP can provide some more information on what they really are trying to achieve.

[palash de]

Thank you so much Stephen