r - Applying functions to vector elements to make rows in a new dataframe -

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i've got interesting problem , have no idea begin -- in fact, wasn't sure how title question! want apply functions elements of dataframe , use these make new rows in new dataframe. example, suppose have dataframe df1 gives x , y data various states:

df1 <- data.frame(state=c("al","ak"), x=c(1,3), y=c(2,4))

what start first state al, , make new dataframe df2with 3 rows, new values of df2$x calculated using 3 different functions give, example: df1$x, df1$x - 1, , df1$x + 1. likewise, want similar thing new values of df2$y, in example calculated df1$y, df1$y * 0.5, , df1$y * 0.5.

then, proceed next state. end result should be:

df2 <- data.frame(state=c("al", "al","al","ak","ak","ak"),                        x=c(1,0,2,3,2,4), y=c(2,1,1,4,2,2))

does know how might approach this? have no idea begin... can imagine kind of loop, i'm hoping there's more elegant approach in r.

base r solution:

funcs.x <- list(function(x) x, function(x) x-1, function(x) x+1) funcs.y <- list(function(y) y, function(y) y*0.5, function(y) y*0.5)  apply.funcs <- function(funcs,x) as.vector(t(sapply(funcs, function(f) f(x))))  d <- data.frame(state = rep(df1$state,each=length(funcs.x)),                 x = apply.funcs(funcs.x, df1$x),                 y = apply.funcs(funcs.y, df1$y)                 )  identical(d,df2) # [1] true

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