control.phaseplot.streamlines

control.phaseplot.streamlines(sys, pointdata, timedata=1, gridspec=None, gridtype=None, dir=None, ax=None, _check_kwargs=True, suppress_warnings=False, **kwargs)[source]

Plot stream lines in the phase plane.

This function plots stream lines for a two-dimensional state space system.

Parameters

  • sys (NonlinearIOSystem or callable(t, x, ...)) – I/O system or function used to generate phase plane data. If a function is given, the remaining arguments are drawn from the params keyword.

  • pointdata (list or 2D array) – List of the form [xmin, xmax, ymin, ymax] describing the boundaries of the phase plot or an array of shape (N, 2) giving points of at which to plot the vector field.

  • timedata (int or list of int) – Time to simulate each streamline. If a list is given, a different time can be used for each initial condition in pointdata.

  • gridtype (str, optional) – The type of grid to use for generating initial conditions: ‘meshgrid’ (default) generates a mesh of initial conditions within the specified boundaries, ‘boxgrid’ generates initial conditions along the edges of the boundary, ‘circlegrid’ generates a circle of initial conditions around each point in point data.

  • gridspec (list, optional) – If the gridtype is ‘meshgrid’ and ‘boxgrid’, gridspec gives the size of the grid in the x and y axes on which to generate points. If gridtype is ‘circlegrid’, then gridspec is a 2-tuple specifying the radius and number of points around each point in the pointdata array.

  • dir (str, optional) – Direction to draw streamlines: ‘forward’ to flow forward in time from the reference points, ‘reverse’ to flow backward in time, or ‘both’ to flow both forward and backward. The amount of time to simulate in each direction is given by the timedata argument.

  • params (dict or list, optional) – Parameters to pass to system. For an I/O system, params should be a dict of parameters and values. For a callable, params should be dict with key ‘args’ and value given by a tuple (passed to callable).

  • color (str) – Plot the streamlines in the given color.

  • ax (matplotlib.axes.Axes) – Use the given axes for the plot, otherwise use the current axes.

  • rcParams (dict) – Override the default parameters used for generating plots. Default is set by config.default[‘ctrlplot.rcParams’].

  • suppress_warnings (bool, optional) – If set to True, suppress warning messages in generating trajectories.

Returns

out

Return type

list of Line2D objects