matlab - vectorization for array products -

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how can vectorize loop ?

let b = real array of size (2,3)

m = real array of size (7,2)

y = real array of size (n,3)

b , m constant , n "big" (in problem, n > 80000).

i want optimize (vectorize) loop :

for k=1:max(size(y))     r=b*y(k,:)';     p(k)=r'*m; end

help appreciated

first p(k)=r'*m wrong

(b*y(k,:)' (2x1) , m (7x2))

so think mean p(k)=r'*m';

then

b (2x3)

y (nx3)

r= b*y' (2xn)

r' (nx2)

m' (2x7)

p=r'*m' (nx7)

so don't need use loop , can write:

p=(b*y')'m' or p=(m(b*y'))'


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