Adding two matrixes with different row numbers.

1 回表示 (過去 30 日間)
Santos García Rosado
Santos García Rosado 2021 年 2 月 26 日
Hi Mathworks community!
I have a matrix A(mxn) and a matrix B(lxn) such as:
A = [1,2,3,4,5,6,7,8,9,10; 10,11,12,13,14,15,16,17,18,19; 19,20,21,22,23,24,25,26,27,28];
B = [1,2,3,4,5,6,7,8,9,10; 2,4,6,8,10,12,14,18,18,20];
I'd like to get an output such as:
out = [sum(A(1,:),B(1,:)); sum(A(1,:),B(2,:)); sum(A(2,:),B(1,:)); sum(A(2,:),B(2,:)); sum(A(3,:),B(1,:)); sum(A(3,:),B(2,:))];
Any idea about how I could code this efficiently?
Thank's in advance!
Santos García

採用された回答

Stephen23
Stephen23 2021 年 2 月 26 日
A = [1,2,3,4,5,6,7,8,9,10; 10,11,12,13,14,15,16,17,18,19; 19,20,21,22,23,24,25,26,27,28];
B = [1,2,3,4,5,6,7,8,9,10; 2,4,6,8,10,12,14,18,18,20];
[Y,X] = ndgrid(1:size(B,1),1:size(A,1));
out = A(X(:),:) + B(Y(:),:)
out = 6×10
2 4 6 8 10 12 14 16 18 20 3 6 9 12 15 18 21 26 27 30 11 13 15 17 19 21 23 25 27 29 12 15 18 21 24 27 30 35 36 39 20 22 24 26 28 30 32 34 36 38 21 24 27 30 33 36 39 44 45 48
  1 件のコメント
Santos García Rosado
Santos García Rosado 2021 年 2 月 26 日
Great Stephen! I really appreciate avoiding a loop. Thank's for the help!

サインインしてコメントする。

その他の回答 (1 件)

Hernia Baby
Hernia Baby 2021 年 2 月 26 日
Following your output image,
out = [sum(A(1,:),B(1,:)); sum(A(1,:),B(2,:)); sum(A(2,:),B(1,:)); sum(A(2,:),B(2,:)); sum(A(3,:),B(1,:)); sum(A(3,:),B(2,:))];
the code is like below
A = [1,2,3,4,5,6,7,8,9,10; 10,11,12,13,14,15,16,17,18,19; 19,20,21,22,23,24,25,26,27,28];
B = [1,2,3,4,5,6,7,8,9,10; 2,4,6,8,10,12,14,18,18,20];
A_sum = sum(A,2);
B_sum = sum(B,2);
for i = 1:length(A_sum)
for j = 1:length(B_sum)
C(i,j) = A_sum(i) + B_sum(j);
end
end
out = rehape(C,[],1);
  1 件のコメント
Santos García Rosado
Santos García Rosado 2021 年 2 月 26 日
Thank's Hernia. Your code works fine!

サインインしてコメントする。

カテゴリ

Help Center および File ExchangeResizing and Reshaping Matrices についてさらに検索

製品


リリース

R2020b

Community Treasure Hunt

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

Start Hunting!

Translated by