[R] Element-by-element multiplication

[Jim Lemon]

Hi Steven,

as.data.frame(sapply(a,"*",p))

Jim


On Mon, May 23, 2016 at 8:22 AM, Steven Yen <syen04 at gmail.com> wrote:
> Dear R users:
>
>  > # p is a vector if length 10
>  > # a is a vector if length 3
>  > # I like to create a matrix with
>  > # the first  column being p multiplied by a[1]
>  > # the second column being p multiplied by a[2]
>  > # the third  column being p multiplied by a[3]
>  > # The following would do that:
>  >
>  > a<-c(10,100,1000); a
> [1]   10  100 1000
>  > p<-matrix(1:10,nrow=10); p
>        [,1]
>   [1,]    1
>   [2,]    2
>   [3,]    3
>   [4,]    4
>   [5,]    5
>   [6,]    6
>   [7,]    7
>   [8,]    8
>   [9,]    9
> [10,]   10
>  > cbind(a[1]*p,a[2]*p,a[3]*p)
>        [,1] [,2]  [,3]
>   [1,]   10  100  1000
>   [2,]   20  200  2000
>   [3,]   30  300  3000
>   [4,]   40  400  4000
>   [5,]   50  500  5000
>   [6,]   60  600  6000
>   [7,]   70  700  7000
>   [8,]   80  800  8000
>   [9,]   90  900  9000
> [10,]  100 1000 10000
>  >
>  > # Gauss does it easily with an element-by-element
>  > # multiplicationa.*p
>  > # How can I do this in R?
>  >
>
>
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>
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