R programming error sum of products

Question

I'm trying to find the sum of products of two different data frames.

data<-a1 a2 a3 a4
      4   6  8  5

Here, a1 a2 a3 a4 are column names

The other data frame is:

data2<-p1 p2 p3 p4
        3  4  5  6
        5  6  8  4
        4  6  6  8
        3  5  8  9

my result should be like this:

result <- a1*P1+a2*p2+a3*p3*a4*p4    

result1 <- 4*3+6*4+8*5+5*6   

result2 <- 4*5+6*6+8*8+5*4   

and so on...

How can this be done?

Answer 1

Best soln is to integrate R linear algebra:

> as.matrix(data2) %*% unlist(data)
#     [,1] 
#[1,]  106
#[2,]  140 
#[3,]  140
#[4,]  151

or you can sweep:

> rowSums(sweep(as.matrix(data2), 2, unlist(data), `*`))
#[1] 106 140 140 151

Where data is:

data=data.frame(a=4,b=6,c=8,d=5)
data2=data.frame(a=c(3,5,4,3),b=c(4,6,6,5),c=c(5,8,6,8),d=c(6,4,8,9))