Emacs: Kill Running Python Script

I don't know if this is a bug with matplotlib/python but running the following from emacs removes my ability to kill the matplotlib process by clicking [x] on the figure window, it

Solution 1:

C-c C-\ will kill the program with a SIGQUIT, but that is not a graceful way to end the program.

Alternatively, if you change the backend to TkAgg, C-c C-c will also terminate the program (again ungracefully), but trying to close the window will still not work.

import numpy as np
   import matplotlib as mpl
   mpl.use('TkAgg') # dothis before importing pyplot
   import matplotlib.pyplot as plt

A full, robust solution requires removing plt.ion(), using a GUI framework like Tk, pygtk, wxpython or pyqt, and embedding the GUI window in a matplotlib FigureCanvas.

---

Here is an example using Tk:

"""
http://stackoverflow.com/q/13660042/190597
Simple circular box simulator, part of part_sim
Restructure to import into gravity() or coloumb () or wind() or pressure()
Or to use all forces: sim_full()
Note: Implement crashing as backbone to all forces
"""import tkinter as tk
import numpy as np
import matplotlib.pyplot as plt
import matplotlib.figure as mplfig
import scipy.spatial.distance as dist
import matplotlib.backends.backend_tkagg as tkagg

classApp(object):
    def__init__(self, master):
        self.master = master
        self.fig = mplfig.Figure(figsize = (5, 4), dpi = 100)
        self.ax = self.fig.add_subplot(111)
        self.canvas = canvas = tkagg.FigureCanvasTkAgg(self.fig, master)
        canvas.get_tk_widget().pack(side = tk.TOP, fill = tk.BOTH, expand = 1)
        self.toolbar = toolbar = tkagg.NavigationToolbar2TkAgg(canvas, master)
        self.button = button = tk.Button(master, text = 'Quit', command = master.quit)
        button.pack(side = tk.BOTTOM)
        toolbar.update()
        self.update = self.animate().__next__
        master.after(10, self.update) 
        canvas.show()

    defanimate(self):
        N = 100#Number of particles
        R = 10000#Box width
        pR= 5#Particle radius

        r = np.random.randint(0, R, (N,2))                  #Position vector
        v = np.random.randint(-R/100,R/100,(N,2))           #velocity vector
        a = np.array([0,-10])                               #Forces
        v_limit = R/2#Speedlimit

        line, = self.ax.plot([],'o')
        line2, = self.ax.plot([],'o')                           #Track a particle
        self.ax.set_xlim(0, R+pR)
        self.ax.set_ylim(0, R+pR)        

        whileTrue:
            v=v+a                                           #Advance
            r=r+v

            #Collision tests
            r_hit_x0 = np.where(r[:,0]<0)                   #Hit floor?
            r_hit_x1 = np.where(r[:,0]>R)                   #Hit roof?
            r_hit_LR = np.where(r[:,1]<0)                   #Left wall?
            r_hit_RR = np.where(r[:,1]>R)                   #Right wall?#Stop at walls
            r[r_hit_x0,0] = 0
            r[r_hit_x1,0] = R
            r[r_hit_LR,1] = 0
            r[r_hit_RR,1] = R

            #Reverse velocities
            v[r_hit_x0,0] = -0.9*v[r_hit_x0,0]
            v[r_hit_x1,0] = -v[r_hit_x1,0]
            v[r_hit_LR,1] = -0.95*v[r_hit_LR,1]
            v[r_hit_RR,1] = -0.99*v[r_hit_RR,1]

            #Collisions
            D = dist.squareform(dist.pdist(r))
            ind1, ind2 = np.where(D < pR)
            unique = (ind1 < ind2)
            ind1 = ind1[unique]
            ind2 = ind2[unique]

            for i1, i2 inzip(ind1, ind2):
                eps = np.random.rand()
                vtot= v[i1,:]+v[i2,:]
                v[i1,:] = -(1-eps)*vtot
                v[i2,:] = -eps*vtot

            line.set_ydata(r[:,1])
            line.set_xdata(r[:,0])
            line2.set_ydata(r[:N//5,1])
            line2.set_xdata(r[:N//5,0])
            self.canvas.draw()
            self.master.after(1, self.update) 
            yielddefmain():
    root = tk.Tk()
    app = App(root)
    tk.mainloop()

if __name__ == '__main__':
    main()