def plot_phase_plane(x, y, indices=None, plot=None, names=None, ax=None, **
    kwargs):
    """ Plot the phase portrait of two dependent variables

    Parameters
    ----------
    x: array_like
        Values of the independent variable.
    y: array_like
        Values of the dependent variables.
    indices: pair of integers (default: None)
        What dependent variable to plot for (None => (0, 1)).
    plot: callable (default: None)
        Uses ``matplotlib.pyplot.plot`` if ``None``
    names: iterable of strings
        Labels for x and y axis.
    \\*\\*kwargs:
        Keyword arguemtns passed to ``plot()``.

    """
    if indices is None:
        indices = 0, 1
    if len(indices) != 2:
        raise ValueError('Only two phase variables supported at the moment')
    if ax is None:
        import matplotlib.pyplot as plt
        ax = plt.subplot(1, 1, 1)
    if names is not None:
        ax.set_xlabel(names[indices[0]])
        ax.set_ylabel(names[indices[1]])
    ax.plot(y[:, (indices[0])], y[:, (indices[1])], **kwargs)
