dot product between two different size of matrix

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Alan 2020-12-18

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评论： James Tursa 2021-12-14

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!

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Ive J 2020-12-18

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

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Alan 2020-12-18

Thank you! This is what I want.

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James Tursa 2020-12-18

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

C = B * A';

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Prajwal Sridhar 2021-12-9

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

James Tursa 2021-12-14

@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.

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