multiplying a 1xM vector by a KxN matrix
5 Ansichten (letzte 30 Tage)
Ältere Kommentare anzeigen
Hello there,
I have a 1xM vector, say V=[1 -1]; I would like to multiply it by a KxN matrix, say S=[0 0 1 1;1 1 0 0;1 0 1 0;0 1 0 1] such that at the beginning the first element of V gets multiplied by the first columns of S, then the second element of V be multiplied by the first columns of S, then the first element of V gets multiplied by the second column of of S, followed by the multiplication of the second element of V by the second column of S, and so forth. That is for the example mentioned above I get: [0 0 0 0 1 -1 1 -1;1 -1 1 -1 0 0 0 0;1 -1 0 0 1 -1 0 0;0 0 1 -1 0 01 -1]. I would appreciate if somebody can help me please. Thank you!
0 Kommentare
Akzeptierte Antwort
Stephen23
am 9 Nov. 2015
Bearbeitet: Stephen23
am 9 Nov. 2015
Use bsxfun, reshape, and permute:
>> V = [1,-1]
V =
1 -1
>> S = [0,0,1,1; 1,1,0,0; 1,0,1,0; 0,1,0,1]
S =
0 0 1 1
1 1 0 0
1 0 1 0
0 1 0 1
>> X = bsxfun(@times,S,reshape(V,1,1,[]));
>> reshape(permute(X,[3,2,1]),[],size(S,1)).'
ans =
0 0 0 0 1 -1 1 -1
1 -1 1 -1 0 0 0 0
1 -1 0 0 1 -1 0 0
0 0 1 -1 0 0 1 -1
0 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!