Difference between revisions of "Figure 5.3: Phase portraits"
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damposc = ct.nlsys(damposc_update, states=2, params=damposc_params) | damposc = ct.nlsys(damposc_update, states=2, params=damposc_params) | ||
− | # Set the | + | # Set the limits for the plot |
limits = [-1, 1, -1, 1] | limits = [-1, 1, -1, 1] | ||
# Vector field | # Vector field | ||
fbs.figure('mlh') | fbs.figure('mlh') | ||
− | ct. | + | ct.phase_plane_plot( |
− | + | damposc, limits, plot_streamlines=False, | |
− | plt. | + | plot_vectorfield=True, gridspec=[15, 12]) |
+ | plt.suptitle(""); plt.title("Vector field") | ||
fbs.savefig('figure-5.3-phase_portraits-vf.png') | fbs.savefig('figure-5.3-phase_portraits-vf.png') | ||
Line 43: | Line 44: | ||
fbs.figure('mlh') | fbs.figure('mlh') | ||
ct.phase_plane_plot(damposc, limits, 8) | ct.phase_plane_plot(damposc, limits, 8) | ||
− | plt.suptitle("Phase portrait") | + | plt.suptitle(""); plt.title("Phase portrait") |
fbs.savefig('figure-5.3-phase_portraits-sl.png') | fbs.savefig('figure-5.3-phase_portraits-sl.png') | ||
</nowiki> | </nowiki> |
Latest revision as of 01:09, 7 April 2024
Chapter | Dynamic Behavior |
---|---|
Figure number | 5.3 |
Figure title | Phase portraits |
GitHub URL | https://github.com/murrayrm/fbs2e-python/blob/main/figure-5.3-phase portraits.py |
Requires | python-control |
Figure 5.3: Phase portraits. (a) This plot shows the vector field for a planar dynamical system. Each arrow shows the velocity at that point in the state space. (b) This plot includes the solutions (sometimes called streamlines) from different initial conditions, with the vector field superimposed.
# phase_portraits.py - phase portrait examples # RMM, 6 Apr 2024 import matplotlib.pyplot as plt import numpy as np import control as ct import control.phaseplot as pp import fbs # FBS plotting customizations # Oscillator parameters damposc_params = {'m': 1, 'b': 1, 'k': 1} # System model (as ODE) def damposc_update(t, x, u, params): m, b, k = params['m'], params['b'], params['k'] return np.array([x[1], -k/m * x[0] - b/m * x[1]]) damposc = ct.nlsys(damposc_update, states=2, params=damposc_params) # Set the limits for the plot limits = [-1, 1, -1, 1] # Vector field fbs.figure('mlh') ct.phase_plane_plot( damposc, limits, plot_streamlines=False, plot_vectorfield=True, gridspec=[15, 12]) plt.suptitle(""); plt.title("Vector field") fbs.savefig('figure-5.3-phase_portraits-vf.png') # Streamlines fbs.figure('mlh') ct.phase_plane_plot(damposc, limits, 8) plt.suptitle(""); plt.title("Phase portrait") fbs.savefig('figure-5.3-phase_portraits-sl.png')