healthyR.ts (version 0.3.1)

ts_velocity_vec: Vector Function Time Series Acceleration

Description

Takes a numeric vector and will return the velocity of that vector.

Usage

ts_velocity_vec(.x)

Value

A numeric vector

Arguments

.x

A numeric vector

Author

Steven P. Sanderson II, MPH

Details

Takes a numeric vector and will return the velocity of that vector. The velocity of a time series is computed by taking the first difference, so $$x_t - x_t1$$

This function can be used on it's own. It is also the basis for the function ts_velocity_augment().

See Also

Other Vector Function: ts_acceleration_vec(), ts_growth_rate_vec()

Examples

suppressPackageStartupMessages(library(dplyr))

len_out    = 25
by_unit    = "month"
start_date = as.Date("2021-01-01")

data_tbl <- tibble(
  date_col = seq.Date(from = start_date, length.out = len_out, by = by_unit),
  a    = rnorm(len_out),
  b    = runif(len_out)
)

vec_1 <- ts_velocity_vec(data_tbl$b)

plot(data_tbl$b)
lines(data_tbl$b)
lines(vec_1, col = "blue")