Plot phase portrait — plotPhasePortrait • PhysioMoCap

Creates a phase portrait (angle vs angular velocity) for analyzing movement dynamics and coordination patterns.

Usage

plotPhasePortrait(
  angle,
  velocity = NULL,
  sampling_rate = 100,
  groups = NULL,
  normalize = FALSE,
  title = "Phase Portrait"
)

Arguments

angle: Angle time series (vector or matrix).
velocity: Angular velocity. If NULL, computed from angle.
sampling_rate: Sampling rate (needed if velocity computed).
groups: Optional grouping factor.
normalize: Logical; normalize to unit circle.
title: Plot title.

Value

A ggplot object.

References

Wickham H (2016). "ggplot2: Elegant Graphics for Data Analysis." Springer.

See also

computeVelocity() for computing angular velocities from position data, plotGaitCycle() for time-domain gait cycle visualization.

Examples

# Phase portrait of knee angle
set.seed(123)
t <- seq(0, 2*pi, length.out = 100)
angle <- sin(t) * 60
velocity <- cos(t) * 60 * (2*pi/100)  # Derivative

plotPhasePortrait(angle, velocity)