Bode Plot Visualization

This module provides the BodePlot class for creating Bode plot visualizations of control systems.

BodePlot Class

class BodePlot(system, freq_range=None, magnitude_yrange=None, phase_yrange=None, color=ManimColor('#58C4DD'), stroke_width=2.5, mag_label='Magnitude (dB)', phase_label='Phase (deg)', xlabel='Frequency (rad/s)', font_size_ylabels=20, font_size_xlabel=20, y_length_mag=None, y_length_phase=None, x_length=None, **kwargs)[source]

Bases: VGroup

__init__(system, freq_range=None, magnitude_yrange=None, phase_yrange=None, color=ManimColor('#58C4DD'), stroke_width=2.5, mag_label='Magnitude (dB)', phase_label='Phase (deg)', xlabel='Frequency (rad/s)', font_size_ylabels=20, font_size_xlabel=20, y_length_mag=None, y_length_phase=None, x_length=None, **kwargs)[source]

Generates a Bode plot visualization as a Manim VGroup for continuous- or discrete-time systems.

This class takes a system representation (transfer function, poles/zeros, or state-space) and visualizes its frequency response with magnitude (in dB) and phase (in degrees) plots. It supports automatic range determination, customizable axes, grid display, and stability analysis.

Parameters:

  • system (various) – System representation, which can be one of: - scipy.signal.lti or transfer function coefficients (list/tuple of arrays) - Symbolic expressions for numerator/denominator (using ‘s’ as variable) - Tuple of (numerator_expr, denominator_expr) as strings or sympy expressions

  • freq_range (tuple[float] | None) – Frequency range in rad/s as (min_freq, max_freq). If None, automatically determined.

  • magnitude_yrange (tuple[float] | None) – Magnitude range in dB as (min_db, max_db). If None, automatically determined.

  • phase_yrange (tuple[float] | None) – Phase range in degrees as (min_deg, max_deg). If None, automatically determined.

  • color (str) – Color of the Bode plot curves (default: BLUE).

  • stroke_width (float) – Stroke width of the plot curves (default: 2).

  • mag_label (str) – Label for the magnitude axis (default: “Magnitude (dB)”).

  • phase_label (str) – Label for the phase axis (default: “Phase (deg)”).

  • xlabel (str) – Label for the frequency axis (default: “Frequency (rad/s)”).

  • font_size_ylabels (int) – Font size for y-axis labels (default: 20).

  • font_size_xlabel (int) – Font size for x-axis label (default: 20).

  • y_length_mag (float) – The vertical length of the magnitude plot

  • y_length_phase (float) – The vertical length of the phase plot

  • x_length (float) – The horizontal length of the plots

  • **kwargs (Any) – Additional keyword arguments passed to the VGroup constructor.

Returns:

A Manim VGroup containing: - Magnitude plot with logarithmic frequency axis and linear dB scale - Phase plot with logarithmic frequency axis and linear degree scale - Axis labels and ticks - Optional grid lines, title, and stability indicators

Return type:

VGroup

show_magnitude(show=True)[source]

Show or hide the magnitude plot and all its components. :param show: If true shows the magnitude plot :type show: bool

show_phase(show=True)[source]

Show or hide the phase plot and all its components. :param show: If true shows the phase plot :type show: bool

grid_on()[source]

Turn on the grid lines.

grid_off()[source]

Turn off the grid lines.

title(text, font_size=30, color=ManimColor('#FFFFFF'), use_math_tex=False)[source]

Add a title to the Bode plot.

Parameters:

  • text (str) – The title

  • font_size (float) – Font size of the title

  • use_math_tex (bool) – Boolean which determines whether to render as LaTeX or regular text

show_asymptotes(color=ManimColor('#F7D96F'), add_directly=True, **kwargs)[source]

Plot asymptotes of the Bode plot.

Parameters:

  • color (Manim color) – Color of the asymptotes

  • add_directly (bool) – If true, the asymptotes are added directly to the Bode plot. To animate the asymptotes set add_directly to false

  • **kwargs (any) – Any arguments to be passed to Line: -stroke_width: Thickness of the asymptote lines -stroke_opacity: Opacity of the asymptote lines

show_margins(show_values=True, show_pm=True, show_gm=True, gm_in_dB=True, pm_color=ManimColor('#83C167'), add_directly=True, gm_color=ManimColor('#F7D96F'), text_color_white=True, font_size=24, gm_label=None, pm_label=None, pm_label_pos=array([-1., -1., 0.]), gm_label_pos=array([1., 1., 0.]), **kwargs)[source]

Shows gain and phase margins on the Bode plot if finite.

Parameters:

  • show_values (Whether to display the numerical values of the margins)

  • margin_color (-)

  • text_color (-)

highlight_critical_points()[source]

Return animations for highlighting critical points.

__init__(system, freq_range=None, magnitude_yrange=None, phase_yrange=None, color=ManimColor('#58C4DD'), stroke_width=2.5, mag_label='Magnitude (dB)', phase_label='Phase (deg)', xlabel='Frequency (rad/s)', font_size_ylabels=20, font_size_xlabel=20, y_length_mag=None, y_length_phase=None, x_length=None, **kwargs)[source]

Generates a Bode plot visualization as a Manim VGroup for continuous- or discrete-time systems.

This class takes a system representation (transfer function, poles/zeros, or state-space) and visualizes its frequency response with magnitude (in dB) and phase (in degrees) plots. It supports automatic range determination, customizable axes, grid display, and stability analysis.

Parameters:

  • system (various) – System representation, which can be one of: - scipy.signal.lti or transfer function coefficients (list/tuple of arrays) - Symbolic expressions for numerator/denominator (using ‘s’ as variable) - Tuple of (numerator_expr, denominator_expr) as strings or sympy expressions

  • freq_range (tuple[float] | None) – Frequency range in rad/s as (min_freq, max_freq). If None, automatically determined.

  • magnitude_yrange (tuple[float] | None) – Magnitude range in dB as (min_db, max_db). If None, automatically determined.

  • phase_yrange (tuple[float] | None) – Phase range in degrees as (min_deg, max_deg). If None, automatically determined.

  • color (str) – Color of the Bode plot curves (default: BLUE).

  • stroke_width (float) – Stroke width of the plot curves (default: 2).

  • mag_label (str) – Label for the magnitude axis (default: “Magnitude (dB)”).

  • phase_label (str) – Label for the phase axis (default: “Phase (deg)”).

  • xlabel (str) – Label for the frequency axis (default: “Frequency (rad/s)”).

  • font_size_ylabels (int) – Font size for y-axis labels (default: 20).

  • font_size_xlabel (int) – Font size for x-axis label (default: 20).

  • y_length_mag (float) – The vertical length of the magnitude plot

  • y_length_phase (float) – The vertical length of the phase plot

  • x_length (float) – The horizontal length of the plots

  • **kwargs (Any) – Additional keyword arguments passed to the VGroup constructor.

Returns:

A Manim VGroup containing: - Magnitude plot with logarithmic frequency axis and linear dB scale - Phase plot with logarithmic frequency axis and linear degree scale - Axis labels and ticks - Optional grid lines, title, and stability indicators

Return type:

VGroup

animation_overrides = {}
grid_off()[source]

Turn off the grid lines.

grid_on()[source]

Turn on the grid lines.

highlight_critical_points()[source]

Return animations for highlighting critical points.

show_asymptotes(color=ManimColor('#F7D96F'), add_directly=True, **kwargs)[source]

Plot asymptotes of the Bode plot.

Parameters:

  • color (Manim color) – Color of the asymptotes

  • add_directly (bool) – If true, the asymptotes are added directly to the Bode plot. To animate the asymptotes set add_directly to false

  • **kwargs (any) – Any arguments to be passed to Line: -stroke_width: Thickness of the asymptote lines -stroke_opacity: Opacity of the asymptote lines

show_magnitude(show=True)[source]

Show or hide the magnitude plot and all its components. :param show: If true shows the magnitude plot :type show: bool

show_margins(show_values=True, show_pm=True, show_gm=True, gm_in_dB=True, pm_color=ManimColor('#83C167'), add_directly=True, gm_color=ManimColor('#F7D96F'), text_color_white=True, font_size=24, gm_label=None, pm_label=None, pm_label_pos=array([-1., -1., 0.]), gm_label_pos=array([1., 1., 0.]), **kwargs)[source]

Shows gain and phase margins on the Bode plot if finite.

Parameters:

  • show_values (Whether to display the numerical values of the margins)

  • margin_color (-)

  • text_color (-)

show_phase(show=True)[source]

Show or hide the phase plot and all its components. :param show: If true shows the phase plot :type show: bool

title(text, font_size=30, color=ManimColor('#FFFFFF'), use_math_tex=False)[source]

Add a title to the Bode plot.

Parameters:

  • text (str) – The title

  • font_size (float) – Font size of the title

  • use_math_tex (bool) – Boolean which determines whether to render as LaTeX or regular text

System Input Formats

The BodePlot class accepts multiple system representation formats:

  1. Scipy LTI objects: signal.TransferFunction, signal.ZerosPolesGain, signal.StateSpace

  2. Coefficient tuples: (numerator_coeffs, denominator_coeffs)

  3. Symbolic expressions: Strings or sympy expressions using ‘s’ as variable

  4. Transfer function strings: "s/(s^2 + 1)" or "s/(s^2 + 1)/1"

Notes

  • The class automatically handles phase unwrapping and DC gain alignment

  • Frequency ranges are automatically determined based on system poles/zeros

  • Grid lines and labels are dynamically scaled based on plot ranges