Count reaching movement units

Counts accepted speed peaks as movement units (submovements). A peak must exceed both a relative height threshold and a relative prominence threshold.

Usage

movementUnits(
  speed,
  fs = NULL,
  height_frac = 0.05,
  prominence_frac = 0.1,
  min_peak_distance = NULL
)

Arguments

speed

Numeric non-negative tangential-speed profile.

fs

Optional sampling frequency in Hz. Required only when min_peak_distance is supplied.

height_frac

Peak-height threshold as a fraction of maximum speed.

prominence_frac

Minimum peak prominence as a fraction of maximum speed.

min_peak_distance

Optional minimum inter-peak interval in seconds.

Value

Integer movement-unit count. Accepted 1-based peak indices are stored in the "peaks" attribute.

References

Rohrer B, Fasoli S, Krebs HI, et al. (2002). Movement smoothness changes during stroke recovery. Journal of Neuroscience, 22:8297-8304.

Examples

t <- seq(0, 1, length.out = 500)
speed <- exp(-((t - 0.3) / 0.04)^2) + exp(-((t - 0.7) / 0.04)^2)
movementUnits(speed)
#> [1] 2
#> attr(,"peaks")
#> [1] 151 350