Matlab bsxfun(@times,...,...) equivalent in R -


has r got equivalent of matlab bsxfun(@times,a,b)? suppose 1 perform element wise multiplication on matrix a,b:

matlab:

a=[1 0 3 -4]; b=[0 1 5 7; 2 9 -3 4];  bsxfun(@times,a,b) = [0 0 15 -28; 2 0 -9 -16]

r:

a<-c(1,0,3,-4) b<-matrix(c(0,2,1,9,5,-3,7,4),nrow = 2,ncol = 4)  * b = matrix(c(0,0,3,-36,5,0,21,-16),nrow = 2,ncol = 4)

any idea on way r gets results of above of a*b, expecting identical matlab bsxfun(@times,a,b)

edit:

bsxfun("*",repmat(a,2,1),b) # using r {pracma}

best

do column major matrices, since r-convention:

> b<-matrix(c(0,2,1,9,5,-3,7,4),nrow = 4,ncol = 2) > a*b      [,1] [,2] [1,]    0    5 [2,]    0    0 [3,]    3   21 [4,]  -36  -16

if take original construction of b bit of unpleasant surprise when try use sweep:

> b2<-matrix(c(0,2,1,9,5,-3,7,4),nrow = 2,ncol = 4) > sweep(b2, 2, a, '*')      [,1] [,2] [,3] [,4] [1,]    0    0   15  -28 [2,]    2    0   -9  -16

since matrix function uses column major filling of postions, , didn't specify byrow=true in call, b-matrix different matlab matrix.

> b3<-matrix(c(0,2,1,9,5,-3,7,4),nrow = 2,ncol = 4, byrow=true) > sweep(b3, 2, a, '*')      [,1] [,2] [,3] [,4] [1,]    0    0    3  -36 [2,]    5    0   21  -16

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