Deutsches R-Forum

Code: Alles auswählen

x <- c(NA, NA, NA, 1, 2, 3, 5, 7, NA, NA, 9, 8, 7)

r <- rle(is.na(x))
if (r$values[1]) x[1:r$lengths[1]] <- 0

Code: Alles auswählen

x <- c(NA, NA, NA, 1, 2, 3, 5, 7, NA, NA, 9, 8, 7)
x[seq(1, min(which(!is.na(x))) - 1)] <- 0
x

Code: Alles auswählen

df <- data.frame(x = c(NA, NA, NA, 1, 2, 3, 5, 7, NA, NA, 9, 8, 7))
df$y <- df$x


foo <- function(x) {
  x[seq(1, min(which(!is.na(x))) - 1)] <- 0
  x
}
foo(df$x)

apply(df, 2, foo)