ggvis integrated into a function

Question

I am trying to create a basic function that you enter the currency and the function returns a ggvis linegraph, but an issue occurs due to the quotation marks

Current code:

ggcurr<-function(curr="AUD"){
    fx<-read.csv("rates.csv")
    fx$date<-as.character(fx$date)
    fx$date<-as.POSIXct(fx$date)
    gginput<-noquote(paste("~",curr,sep=""))

    fx%>%ggvis(~date,gginput)%>%
    layer_lines()
}

This code just returns a straight line.

I have also attempted as.name() to no avail

Many thanks!

All solved, the parse function worked, thank's for those who helped!

Answer 1

In addition to the solution you found with parse, this is the sort of thing that the prop function from ggvis can be used for.

For example, if you wanted to take this simple line graph

mtcars %>% ggvis(~mpg, ~wt) %>% layer_lines()

with the y-variable wt given as a string like you are doing in your function, it would look like this:

curr = "wt"
mtcars %>% ggvis(~mpg, prop("y", as.name(curr))) %>%
    layer_lines()