Hello I was wondering if anyone could help. I am using R to perform random projection on Gaussians. I need to take k Gaussian random vectors U1,...,Uk in R(reals) Then for any vector v in d dimensions, perform the random projection: f(v) = v.U1, v.U2, ..., v.Uk which reduces v from d dimensions to k dimensions So i need v1,...vn so n vectors and then the basic idea is that the relative orders will be preserved between the vectors v after projection ie the nearet neighbours for each vectors will be the same before projection (v1,v2,...,vn) and after projection f(v1),...f(vk) I'm struggling to produce this in R. I've managed to make a matrix for U and V However I now need to use the scalar product to perform the projection, taking each row of v (vi) and multiplying it with every column of the U matrix. I need to perform this for n vectors and have a matrix as the outcome. This would then allow me to find the distances between each f(vi)! Any help would be greatly appreciated, thankyou!
Random projection
2 messages · rosie fleming, Jeff Newmiller
Your multiplication description sounds more like matrix multiplication than scalar multiplication. R supports matrix multiplication with the %*% operator. I didn't follow the rest of your description... are you doing a homework assignment? There is a no homework policy on this list...
On December 4, 2018 2:06:43 PM PST, rosie fleming <rosiefleming at hotmail.co.uk> wrote:
Hello I was wondering if anyone could help. I am using R to perform random projection on Gaussians. I need to take k Gaussian random vectors U1,...,Uk in R(reals) Then for any vector v in d dimensions, perform the random projection: f(v) = v.U1, v.U2, ..., v.Uk which reduces v from d dimensions to k dimensions So i need v1,...vn so n vectors and then the basic idea is that the relative orders will be preserved between the vectors v after projection ie the nearet neighbours for each vectors will be the same before projection (v1,v2,...,vn) and after projection f(v1),...f(vk) I'm struggling to produce this in R. I've managed to make a matrix for U and V However I now need to use the scalar product to perform the projection, taking each row of v (vi) and multiplying it with every column of the U matrix. I need to perform this for n vectors and have a matrix as the outcome. This would then allow me to find the distances between each f(vi)! Any help would be greatly appreciated, thankyou!
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