lead function to shift by one (or more).

lead function to shift by one (or more).

Usage

shift(x, shift_by = 1)

Arguments

x

a vector of values

shift_by

an integer of length 1, giving the number of positions to lead (positive) or lag (negative) by

Details

Lead and lag are useful for comparing values offset by a constant (e.g. the previous or next value)

Taken from: http://ctszkin.com/2012/03/11/generating-a-laglead-variables/

This function allows me to remove the dplyr::lead depends. Still suggest for vignettes though.

Examples

d <- data.frame(x = 1:15)
# generate lead variable
d$df_lead2 <- ggRandomForests:::shift(d$x, 2)
# generate lag variable
d$df_lag2 <- ggRandomForests:::shift(d$x, -2)
#
#