How to multiply a column by vector components? [closed]

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I have a 5 column matrix which I am multiplying by a 5 row vector. Each column should be multiplied by the corresponding element in the vector. I have the information in both data.frame and matrix form - was unsure if it mattered to do matrix operators.

This is the final few minutes of spending at least 6 hours on this today, so I hope the example makes sense. Please excuse the simplicity of the problem, I just cannot think right now and am running short on time.

Ex.

Column 1 has 252 rows. 
Vector = [a,b,c,d,e].
Column 1[1:252] %*% Vector[a]

Column 2 has 252 rows. 
Column 2[1:252] %*% Vector [b]

Column 4 has 194 rows of "NA" or "0".  #I don't know if this changes anything, but thought it useful info.
Column 4[1:252] %*% Vector[d]

Answer 1

m<-matrix(runif(100),ncol=5) #your matrix
r<-c(1:5)               #your vector
t(apply(m,1,function(x)x*r))

Answer 2

This should be faster than apply. It relies on vector recycling.

m<-matrix(rep(1,10),ncol=5) 
#     [,1] [,2] [,3] [,4] [,5]
#[1,]    1    1    1    1    1
#[2,]    1    1    1    1    1
r<-c(1:5)   
t(t(m)*r)
#     [,1] [,2] [,3] [,4] [,5]
#[1,]    1    2    3    4    5
#[2,]    1    2    3    4    5