How to extract diagonal elements of multiple nxn square matrix and place them in single mat file or matrix?
8 Ansichten (letzte 30 Tage)
Ältere Kommentare anzeigen
Sunny
am 27 Sep. 2018
Bearbeitet: Sunny
am 21 Okt. 2018
Hello,
I have 500 mat files with 10x10 double dimension. I want to extract the 10 diagonal elements from each matrix and place them in a single matrix which will be 500x10 (500 rows and 10 columns) each row consists of diagonal elements of one matrix. How can I make a single variable with all the diagonal elements?
Thanks
6 Kommentare
Stephen23
am 28 Sep. 2018
@Varun Mandalapu: note that concatenating onto the output array is not very efficient. For a more efficient solution you should preallocate the output array and use indexing, as ytzhak goussha's answer shows.
Akzeptierte Antwort
ytzhak goussha
am 27 Sep. 2018
Hope this helps
step1:creat a nXnXm with random elements for the example:
%set dimensions of matrix
size_of_matrix=10;
number_of_matricides=500;
mat_input=randi(30,size_of_matrix,size_of_matrix,number_of_matricides);
step2: initialize an output matrix with nXm dimensions
mat_output=zeros(number_of_matricides,size_of_matrix);
step3: extract a diagonal from each matrix and place them in the output matrix
for i=1:number_of_matricides
mat_output(i,:)=diag(mat_input(:,:,i));
end
Alternatively, though not recommended, you can simply concatenate:
%initialize an empty matrix
mat_output=[];
for i=1:number_of_matricides
mat_output=[mat_output;diag(mat_input(:,:,i))'];
end
5 Kommentare
Weitere Antworten (0)
Siehe auch
Kategorien
Mehr zu Operating on Diagonal Matrices finden Sie in Help Center und File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!