[R] Help with combining functions

[Carl Witthoft]

This is the world-famous "fizzbuzz" problem.   You should be able to find
lots of implementations by Googling that word.  Here's a pointless
collection I wrote once:

# a really dumb fizzbuzz alg competition
#fbfun1 is 2.5x faster than fbfun2
# fbfun3 is 10x faster than fbfun1
# fbfun1 is 2x faster than fbfun4 
# fbfun5 is 20x faster than fbrun3
# Those are user times; in most cases the system time is very small indeed. 

fbfun1 <- function(xfoo) {
xfoo<-1:xfoo
fbfoo <- 1+(!as.logical(mod(xfoo,3)))*(as.logical(mod(xfoo,5))) +
2*(as.logical(mod(xfoo,3)))*(!as.logical(mod(xfoo,5)))+3*(!as.logical(mod(xfoo,3)))*(!as.logical(mod(xfoo,5)))

fbbar <- unlist(lapply(fbfoo, function(x)
switch(x,0,'fizz','buzz','fizzbuzz')))
return(fbbar)
}


fbfun3 <- function(xfoo) {
xfoo<-1:xfoo
fbfoo <- 1+(!as.logical(mod(xfoo,3)))*(as.logical(mod(xfoo,5))) +
2*(as.logical(mod(xfoo,3)))*(!as.logical(mod(xfoo,5)))+3*(!as.logical(mod(xfoo,3)))*(!as.logical(mod(xfoo,5)))
fbtab<-cbind(1:4,c('','fizz','buzz','fizzbuzz'))
fbbar <- fbtab[fbfoo,2]
return(fbbar)
}

# can I do it with recycled vectors, e.g. c('','','fizz') and
c('','','','','buzz') ?
fbfun4 <- function(xfoo) {
fiz<- rep(c('','','fizz'),length.out=xfoo)
buz<-rep(c('','','','','buzz'),length.out=xfoo)
fbbar <- unlist(lapply(1:xfoo, function(j)paste(fiz[j],buz[j]) ) )
return(fbbar)
}

# or completely sleazy:
fbfun5 <- function(xfoo) {
fiz<-
rep(c('','','fizz','','buzz','fizz','','','fizz','buzz','','fizz','','','fizzbuzz'),length.out=xfoo)
return(fiz)
}





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