Dot Multiplication in MATLAB

13 次查看（过去 30 天）
Saunok Chakrabarty
Saunok Chakrabarty 2024-2-20
评论： Saunok Chakrabarty 2024-2-22
I am a bit confused about how dot multiplication (.*) works in MATLAB. For example, [1 2]' .* [1 2; 3 4] = [1 2; 6 8]. So it seems that each row of the first matrix is being multiplied by the corresponding row in the second matrix. However, [1 2] .* [1 2 3 4]' = [1 2; 2 4; 3 6; 4 8] - it seems that each column of the first matrix is being multiplied by the column vector in the second matrix. Further, [1 2] .* [1 2; 3 4; 5 6]' is not possible because of size incompatibility.
How is the multiplication being carried out? I am using MATLAB R2021b.

请先登录，再回答此问题。

采纳的回答

Matt J
Matt J 2024-2-20
编辑：Matt J 2024-2-20
For matrices A and B, the rule is generally that A.* B is element-by-element multiplication a(i,j).*b(i,j), which means that normally all dimensions of A and B must be equal. However if ever size(A,n)=1 and size(B,n)~=1 (or vice versa), then A will be implicitly copied along dimension n until size(A,n)=size(B,n) and similarly for B.

更多回答（0 个）

类别

在 Help Center 和 File Exchange 中查找有关 Logical 的更多信息

标签

Community Treasure Hunt

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

Start Hunting!

Translated by