dot product between two different size of matrix

Hello,

I have two matrix, one is A (1by 3 matrix), the other one is B (86 by 3 matrix). And I would like to calculate the dot product of dot(A,B). However, A and B are not the same size, so dot(A,B) function can not be performed successfullly.

How can I calculate the dot product between two different size of matrix without using for loop?

Many thanks!

Answer 1

[Ive J]

X = sum(bsxfun(@times, A, B), 2);

[Alan]

Thank you! This is what I want.

Answer 2

[James Tursa]

Assuming everything is real and by "dot product" you aren't involving complex conjugates, simply this

C = B * A';

[Alan]

Thanks a lot! This method works more efficiently! And it performs in a simple way! Good method!

[Prajwal Sridhar]

Is this same if i have matrix which is 50x2 and 2x2?

[James Tursa]

@Prajwal Sridhar Try it and see if it does what you want. If it doesn't, then open up a new Question and post a small example of inputs and desired output.