sysplot.plot_nyquist

plot_nyquist(real, imag, ax=None, label=None, mirror=True, arrow_position=None, alpha=None, equal_axes=True, arrow_size=None, **kwargs)

Plot a Nyquist diagram with a directional arrow and optional mirror curve.

Draws the frequency response in the complex plane. A directional arrow marks the direction of increasing frequency. The complex conjugate curve (mirror) is rendered at reduced opacity when mirror=True.

Parameters:

• real (ndarray) – Real parts of the frequency response H(jω).

• imag (ndarray) – Imaginary parts of the frequency response H(jω).

• ax (Axes | None) – Axes to plot on. Defaults to the current axes.

• label (str | None) – Legend label for the main curve.

• mirror (bool) – If True, also plots the complex conjugate curve.

• arrow_position (float | None) – Fractional arc-length position (0–1) for the direction arrow. Defaults to nyquist_arrow_position.

• alpha (float | None) – Transparency of the mirror curve. Defaults to nyquist_mirror_alpha.

• equal_axes (bool) – If True, sets equal axis scaling.

• arrow_size (int | None) – Arrow head size (mutation_scale). Defaults to nyquist_arrow_size.

• **kwargs –

  Additional keyword arguments forwarded to matplotlib.axes.Axes.plot() for both the main and mirrored curves.

  If color or linestyle are not provided, they are taken from the active sysplot style cycler. The arrow color follows the resolved curve color.

Return type:

None

Examples using sysplot.plot_nyquist

Plot Nyquist

Plot Nyquist

Quick Start Example

Quick Start Example

rtype:

None