return row index of values greater than 0 to a 3 dimensional array
21 Ansichten (letzte 30 Tage)
Ältere Kommentare anzeigen
Charles
am 21 Apr. 2019
Beantwortet: Andrei Bobrov
am 21 Apr. 2019
I have a Matrix A, of m x n dimensions.
I wish to go through each row from left to right and return the index of values greater than 0. I have tried the folowing which returns the column index for the first row which has values. for example row 26.
I have tried the following but I am not getting the outputmatrix with all entries. I fear the entries are being overwritten
A =[2,-4,-0.5,0.34;0.01,4,-0.5,0.34;-10,4,-0.2,0.6;-10,4,-0.2,0.6;-19,15,-0.7,0.6];
% Now we have input matrix A we want to return the col index of each row element greater than 0.
% inputMatrix= A
outputMatrix=zeros(1,[],size(A,1));
for i = 26:size(A(2:end,:),1)
for ij = 1:size(A(2:end,:),2)
[rows, columns] = find(inputMatrix > 0)
outputMatrix=columns;
end
end
A =
2 -4 -0.5 0.34
0.01 4 -0.5 0.34
-10 4 -0.2 0.6
-10 4 -0.2 0.6
-19 15 -0.7 0.6
However I wish to go through each row, and store these column indices in a 3 dimensional array where each page represents the set of column indices from each row of A
Example output is a 3 dimensional array of column indices. - Matrix E
1, 4 (page 1)
1, 2, 4 (page 2)
2, 4 (page 3
2, 4 (page 4)
2,4 (page 5)
I then want to use these column indices to return the value from the corresponding rows of a matrix C and matrix D. Matrix C and D are the same dimentions as A
I then want to multiply C values by D values and return a 3 dimension array of results. - Matrix F
The results will be of the same dimension as Matrix E
Any help appreciated.
7 Kommentare
Akzeptierte Antwort
Image Analyst
am 21 Apr. 2019
Try this:
A = [2,-4,-0.5,0.34;0.01,4,-0.5,0.34;-10,4,-0.2,0.6;-10,4,-0.2,0.6;-19,15,-0.7,0.6];
[rows, columns] = find(A > 0)
4 Kommentare
Weitere Antworten (1)
Andrei Bobrov
am 21 Apr. 2019
[ii,jj] = find(A > 0);
out = accumarray(ii,jj,[],@(x){sort(x)'});
out{:}
0 Kommentare
Siehe auch
Kategorien
Mehr zu Matrices and Arrays 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!