Sorting and averaging matrices

5 views (last 30 days)
HT
HT on 9 Sep 2019
Commented: Matt J on 16 Sep 2019
  1. I have two matrices. One for example is A = 520 x 1 and it has numbers from 1-8 which are not in order. For every number in this matrix, I have corresponding 1000 samples in another matrix B 520 x 1000. I want to first sort A and arrange numbers from 1-8 for every 8 rows. So output should be (1,2,3,4,5,6,7,8,1,2,3,4,5 and so on) and arrange corresponding values in B also such that they match.
  2. Once this is done, I want to average every 5 rows of B and store it in a new matrix which will be 104 x 1000.
Thanks for the help in advance!
  4 Comments
Guillaume
Guillaume on 9 Sep 2019
100 is not a multiple of 8. Isn't that a problem? Why average every 5 rows when you have groups of size 8?
HT
HT on 9 Sep 2019
It will be a multiple of 8 always. I just took 100 as a random number. I will edit the main question, thank you.

Sign in to comment.

Accepted Answer

Matt J
Matt J on 9 Sep 2019
Edited: Matt J on 10 Sep 2019
[~,idx]=sort( reshape(A,8,[]) ,1);
[m,n]=size(idx);
C=reshape(B,m,n,[]);
[m,n,p]=size(C);
idx=idx+(0:n-1)*m+reshape(0:p-1,1,1,p)*(m*n);
C=mean(reshape(C(idx),5,[]));
result=reshape( C ,m*n/5,[]);
  8 Comments
HT
HT on 16 Sep 2019
How can I save sorted A values in a variable?
Matt J
Matt J on 16 Sep 2019
[Asorted,idx]=sort( reshape(A,8,[]) ,1);

Sign in to comment.

More Answers (0)

Categories

Find more on Shifting and Sorting Matrices in Help Center and File Exchange

Products

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!