IPython Notebook widgets for Matplotlib interactivity

Question

I would like to use the ipython notebook widgets to add some degree of interactivity to inline matplotlib plots.

In general the plot can be quite heavy and I want to on

Answer 1

I have a hacky workaround that will only display one figure. The problem seems to be that there are two points in the code that generate a figure and really, we only want the second one, but we can't get away with inhibiting the first. The workaround is to use the first one for the first execution and the second one for all subsequent ones. Here's some code that works by switching between the two depending on the initialized flag:

%matplotlib inline
import matplotlib.pyplot as plt
from IPython.html.widgets import interact, interactive, fixed
from IPython.html import widgets
from IPython.display import clear_output, display, HTML

class InteractiveCursor(object):
    initialized = False
    fig = None
    ax = None
    vline = None
    hline = None

    def initialize(self):
        self.fig, self.ax = plt.subplots()
        self.ax.plot([3,1,2,4,0,5,3,2,0,2,4])
        self.vline = self.ax.axvline(1)
        self.hline = self.ax.axhline(0.5)

    def set_cursor(self, x, y):
        if not self.initialized:
            self.initialize()

        self.vline.set_xdata((x, x))
        self.hline.set_ydata((y, y))

        if self.initialized:
            display(self.fig)
        self.initialized = True

ic = InteractiveCursor()
def set_cursor(x, y):
    ic.set_cursor(x, y)

interact(set_cursor, x=(1, 9, 0.01), y=(0, 5, 0.01));

My opinion is that this should be considered a bug. I tried it with the object oriented interface and it has the same problem.