A simple centered moving average function.

Source: R/utils.R

This function is defined based on a code chunk found here. This is a centered moving average of arbitrary width.

ma(x, n = 5)

Arguments

x

numeric. Vector to produce a moving average of.
n

integer. The width of the moving average. Default 5 time steps.

Value

Numeric vector of same length as x.

Details

NA values are used as padding on the left and right to make the returned vector of equal length.

Examples

x  <- runif(100)
xx <- cumsum(x)
if (FALSE) {
plot(x)
lines(ma(x))
lines(ma(x),9)
}
# some de facto unit tests:
x <- 1:10
d2 <- ma(x,2) - x
d3 <- ma(x,3) - x
d4 <- ma(x,4) - x
d5 <- ma(x,5) - x
# pop <- sample.int(10, 5, replace = T)
# all should give same for linear data.
stopifnot(all(abs(d2) < 1e-10, na.rm = TRUE))
stopifnot(all(abs(d3) < 1e-10, na.rm = TRUE))
stopifnot(all(abs(d4) < 1e-10, na.rm = TRUE))
stopifnot(all(abs(d5) < 1e-10, na.rm = TRUE))