Add directional movement features

Computes step length, bearing and turn angle from track coordinates. When id and time are supplied, records are sorted by individual and time before features are computed.

Usage

mutate_directional_features(
  data,
  x,
  y,
  id = NULL,
  time = NULL,
  angle_convention = c("mathematical", "bearing")
)

Arguments

data

A data frame.

x, y

Coordinate columns.

id

Optional individual identifier column.

time

Optional time column used for sorting within individual.

angle_convention

Angle convention passed to compute_bearing().

Value

A tibble with added step_length, bearing and turn_angle.

See also

Other movement helpers: as_step_data(), augment_momentuHMM_angles(), compute_bearing(), compute_step_length(), compute_turn_angle(), geom_circular_point(), geom_direction_arrow(), plot_state_angles()

Examples

tibble::tibble(id = 1, time = 1:3, x = 0:2, y = 0) |>
  mutate_directional_features(x = x, y = y, id = id, time = time)
#> # A tibble: 3 × 7
#>      id  time     x     y step_length bearing turn_angle
#>   <dbl> <int> <int> <dbl>       <dbl>   <dbl>      <dbl>
#> 1     1     1     0     0          NA      NA         NA
#> 2     1     2     1     0           1       0         NA
#> 3     1     3     2     0           1       0          0