You are describing an awkward way of doing this (and your example is unreadable
because you are not following posting instructions for the list) ... but the
following contains the essence of what I think is needed: parse() and eval().
v <- character()
v[1] <- sprintf("%d ^ %s", 2, "duck")
v[2] <- sprintf("%d * %s", 4, "crow")
# [1] "2 ^ duck" "4 * crow"
duck <- -2
crow <- pi
eval(parse(text=v[1]))
# [1] 0.25
eval(parse(text=v[2]))
# 12.56637
However, myself, I would not use symbols, but a named vector of values -
unless it's important to you that these are _actually_ symbols. You probably
avoid some conversions from and to symbols.
v1 <- c(2, 4)
v2 <- c(duck = -2, crow = pi)
v1[1] * v2["duck"]
v1[2] * v2["crow"]
You can of course freely interconvert and cast your symbol names to character:
duck <- 100
v2[as.character(quote(duck))] <- duck
v1[1] * v2["duck"]
#[1] 200
B.
On Oct 31, 2015, at 11:52 AM, Judson <judsonbl...@msn.com> wrote:
>
>
> Is
> there a way to multiply a matrix
>
> times
> a vector of symbols?
>
> For
> instance, could I do this:
>
> 1
> 0 0 a
>
> 0 1
> 0 times b
>
> -1 2
> 1 c
>
>
>
> which
> should result in :
>
> a
>
> b
>
> c �a
> -2*b
> where a, b, and c
>
> are
> as yet not assigned numeric values?
>
> ........................... judson blake
>
>
>
> [[alternative HTML version deleted]]
>
> ______________________________________________
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