r - Multiplying one matrix with a set of scalars -

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i have r script systematically perform changes 3x3 matrix scalar multiplication follows

r <- matrix(rexp(9, rate=.1), ncol=3); (i in 1:360) { k = i*r; ... }

and use modified matrix further calculations within loop. however, loop nested inside 2 other loops, making script slow. question is, how can vectorize innermost loop such result instead three-dimensional array of size 3x3x360 where

a[,,i] = i*r;

for ranging 1 360?

how basic multiplication , reshaping

set.seed(15) #for reproducibility r <- matrix(rexp(9, rate=.1), ncol=3); r #           [,1]      [,2]      [,3] # [1,]  2.042281  1.760375 2.9230182 # [2,] 19.466458  6.628580 0.1818078 # [3,]  2.544348 27.541514 4.1325714  dd <- array(sapply(1:360, `*`, r), dim=c(dim(r), 360)) dd[,,1] #           [,1]      [,2]      [,3] # [1,]  2.042281  1.760375 2.9230182 # [2,] 19.466458  6.628580 0.1818078 # [3,]  2.544348 27.541514 4.1325714 dd[,,2] #           [,1]      [,2]      [,3] # [1,]  4.084562  3.520749 5.8460364 # [2,] 38.932916 13.257161 0.3636157 # [3,]  5.088697 55.083027 8.2651427 dd[,,10] #           [,1]      [,2]      [,3] # [1,]  20.42281  17.60375 29.230182 # [2,] 194.66458  66.28580  1.818078 # [3,]  25.44348 275.41514 41.325714

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