route_rolling_diff {stplanr}

Return smoothed differences between vector values

Description

This function calculates a simple rolling mean in base R. It is useful for calculating route characteristics such as mean distances of segments and changes in gradient.

Usage

route_rolling_diff(x, lag = 1, abs = TRUE)

Arguments

x

Numeric vector to smooth

lag

The window size of the smoothing function. The default, 3, will take the mean of values before, after and including each value.

abs

Should the absolute (always positive) change be returned? True by default

See Also

Other route_funs: route_average_gradient(), route_rolling_average(), route_rolling_gradient(), route_sequential_dist(), route_slope_matrix(), route_slope_vector()

Examples

r1 <- od_data_routes[od_data_routes$route_number == 2, ]
y <- r1$elevations
route_rolling_diff(y, lag = 1)
route_rolling_diff(y, lag = 2)
r1$elevations_diff_1 <- route_rolling_diff(y, lag = 1)
r1$elevations_diff_n <- route_rolling_diff(y, lag = 1, abs = FALSE)
d <- cumsum(r1$distances) - r1$distances / 2
diff_above_mean <- r1$elevations_diff_1 + mean(y)
diff_above_mean_n <- r1$elevations_diff_n + mean(y)
plot(c(0, cumsum(r1$distances)), c(y, y[length(y)]), ylim = c(80, 130))
lines(c(0, cumsum(r1$distances)), c(y, y[length(y)]))
points(d, diff_above_mean)
points(d, diff_above_mean_n, col = "blue")
abline(h = mean(y))