Per-trajectory straightness index for a Tracks

Computes [path_straightness()] for each trajectory in a `Tracks`, ordering each trajectory's points by its time column when one is recorded.

Usage

straightness_index(ts, x_col = ts@cols$x, y_col = ts@cols$y)

Arguments

ts

A `Tracks`.

x_col, y_col

Names of the coordinate columns to use. Default to the `Tracks`'s recorded x/y columns (the real recorded positions), so the metric reflects the physical path rather than any display transform.

Value

A `data.frame` with one row per trajectory: the `Tracks`'s id column and a numeric `straightness` column.

See also

[path_straightness()], [tortuosity_ratio()]

Examples

head(straightness_index(cpunctatus))
#>         trial_id straightness
#> 10_1_1    10_1_1   0.71927750
#> 10_10_1  10_10_1   0.09897137
#> 10_11_1  10_11_1   0.79943750
#> 10_12_1  10_12_1   0.82488090
#> 10_13_1  10_13_1   0.63885806
#> 10_14_1  10_14_1   0.93581201