Matrix Multiplication, row by row multiplication and column by column multiplication

42 vues (au cours des 30 derniers jours)
Hi there,
I was wondering what matlab function I can use to multiply a matrix by another matrix and then multiply those two matrices row by row and then column by column. Yielding a total of three matrix multiplications: regular matrix multiplication, row by row multiplication, and column by column multiplication.
Code
%
A = ([ 1 2 3; 4 5 6; 7 8 9]);
B = ([ 2 2 2; 2 2 2 ; 2 2 2]);
%
...For example...
Regular matrix multiplication: A*B = ([12 12 12; 30 30 30; 48 48 48])
%
How can I write it to multiply the matrix row by row and column by column?
Row by row multiplication: RowsA*RowsB = ([12 12 12; 30 30 30; 48 48 48])
Column by column multiplication: ColsA*ColsB = ([12 12 12; 30 30 30; 48 48 48])
Thank you.

Réponse acceptée

madhan ravi
madhan ravi le 11 Sep 2018
Modifié(e) : madhan ravi le 11 Sep 2018
There is no in-built function but you can do this:
A = [ 1 2 3; 4 5 6; 7 8 9]
B = [ 2 2 2; 2 2 2 ; 2 2 2]
A*B %regular matrix multiplication
A.*B %element wise matrix multiplication
[m,n]=size(A)
for i = 1:m
rows(i,:)=A(i,:).*B(i,:) %multiplies rows
end
for i=1:n
columns(:,i)=A(:,i).*B(:,i) % multiplies columns
end
  4 commentaires
Stephen H
Stephen H le 11 Sep 2018
Modifié(e) : Stephen H le 11 Sep 2018
well, I didn't read the question carefully enough... it just says use 'a' built-in function... so I guess I could just use the regular matrix multiplication. thank you for your help

Connectez-vous pour commenter.

Plus de réponses (0)

Catégories

En savoir plus sur Creating and Concatenating Matrices dans Help Center et File Exchange

Community Treasure Hunt

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

Start Hunting!

Translated by