Cumulative sum for positive numbers only

Question

I have this vector :

x = c(1,1,1,1,1,0,1,0,0,0,1,1)

And I want to do a cumulative sum for the positive numbers only. I should have the fol

Answer 1

x=c(1,1,1,1,1,0,1,0,0,0,1,1)
cumsum_ <- function(x) {
  r <- rle(x)
  s <- split(x, rep(seq_along(r$values), rle(x)$lengths))
  return(unlist(sapply(s, cumsum), use.names = F))
}
(xc <- cumsum_(x))
# [1] 1 2 3 4 5 0 1 0 0 0 1 2

Answer 2

x<-c(1,1,1,1,1,0,1,0,0,0,1,1)

skumulowana<-function(x) {
  dl<-length(x)
  xx<-numeric(dl+1)
  for (i in 1:dl){
    ifelse (x[i]==0,xx[i+1]<-0,xx[i+1]<-xx[i]+x[i])
  }
wynik<<-xx[1:dl+1]
return (wynik)
}

skumulowana(x)
## [1] 1 2 3 4 5 0 1 0 0 0 1 2

Answer 3

I dont know much of R but i have written a small code in Python. Logic remains the same in all language. Hope this will help you

x=[1,1,1,1,1,0,1,0,0,0,1,1]
tot=0
for i in range(0,len(x)):
    if x[i]!=0:
        tot=tot+x[i]
        x[i]=tot
    else:
        tot=0
print x