Fastest way to multiply matrix columns with vector elements in R

Question

I have a matrix m and a vector v. I would like to multiply first column of matrix m by the first element of vector v, and

Answer 1

As @Arun points out, I don't know that you'll beat your solution in terms of time efficiency. In terms of code understandability, there are other options though:

One option:

> mapply("*",as.data.frame(m),v)
      V1  V2  V3
[1,] 0.0 0.0 0.0
[2,] 1.5 0.0 0.0
[3,] 1.5 3.5 0.0
[4,] 1.5 3.5 4.5

And another:

sapply(1:ncol(m),function(x) m[,x] * v[x] )