Refresh matplotlib plot in tkinter GUI
I want to update matplotlib plot in tkinter GUI. I tried to do it in the following code example.
import matplotlib
matplotlib.use('TkAgg')
import numpy as np
import matplotlib.pyplot as plt
from matplotlib.backends.backend_tkagg import FigureCanvasTkAgg, NavigationToolbar2TkAgg
from matplotlib.figure import Figure
import tkinter as tk
import tkinter.ttk as ttk
import sys
class Application(tk.Frame):
def __init__(self, master=None):
tk.Frame.__init__(self,master)
self.createWidgets()
def createWidgets(self):
fig=plt.figure(figsize=(8,8))
ax=fig.add_axes([0.1,0.1,0.8,0.8],polar=True)
canvas=FigureCanvasTkAgg(fig,master=root)
canvas.get_tk_widget().grid(row=0,column=1)
canvas.show()
self.plotbutton=tk.Button(master=root, text="plot", command=self.plot)
self.plotbutton.grid(row=0,column=0)
def plot(self):
for line in sys.stdout: #infinite loop, reads data of a subprocess
theta=line[1]
r=line[2]
ax.plot(theta,r,linestyle="None",maker='o')
plt.show(block=False)
plt.pause(0.001)
plt.cla()
#here set axes
root=tk.Tk()
app=Application(master=root)
app.mainloop()
The problem at the moment is that the ax object is not known in the plot function. If I try plot (self, canvas, ax) the GUI won't open. Only the shape that displays data.
I want to write data in a figure that is displayed in the GUI. At least the refresh rate is around 3-5 Hz. Because I'm a complete newbie, this code solution is probably not the best way to do it. So I would be happy if someone could show me a smarter solution.
Thank!
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Ok, I could work it out myself. Here's the solution:
import matplotlib
matplotlib.use('TkAgg')
import numpy as np
import matplotlib.pyplot as plt
from matplotlib.backends.backend_tkagg import FigureCanvasTkAgg, NavigationToolbar2TkAgg
from matplotlib.figure import Figure
import tkinter as tk
import tkinter.ttk as ttk
import sys
class Application(tk.Frame):
def __init__(self, master=None):
tk.Frame.__init__(self,master)
self.createWidgets()
def createWidgets(self):
fig=plt.figure(figsize=(8,8))
ax=fig.add_axes([0.1,0.1,0.8,0.8],polar=True)
canvas=FigureCanvasTkAgg(fig,master=root)
canvas.get_tk_widget().grid(row=0,column=1)
canvas.show()
self.plotbutton=tk.Button(master=root, text="plot", command=lambda: self.plot(canvas,ax))
self.plotbutton.grid(row=0,column=0)
def plot(self,canvas,ax):
for line in sys.stdout: #infinite loop, reads data of a subprocess
theta=line[1]
r=line[2]
ax.plot(theta,r,linestyle="None",maker='o')
canvas.draw()
ax.clear()
#here set axes
root=tk.Tk()
app=Application(master=root)
app.mainloop()
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Thanks to Abishek for taking the time to post an answer to your own problem.
I only slightly modified your answer to work as a standalone module without any input from sys.stdout. Also tkinter import for python 2.7 changed
import matplotlib
matplotlib.use('TkAgg')
import numpy as np
import matplotlib.pyplot as plt
from matplotlib.backends.backend_tkagg import FigureCanvasTkAgg, NavigationToolbar2TkAgg
from matplotlib.figure import Figure
import Tkinter as tk # python 2.7
import ttk # python 2.7
import sys
class Application(tk.Frame):
def __init__(self, master=None):
tk.Frame.__init__(self,master)
self.createWidgets()
def createWidgets(self):
fig=plt.figure(figsize=(8,8))
ax=fig.add_axes([0.1,0.1,0.8,0.8],polar=True)
canvas=FigureCanvasTkAgg(fig,master=root)
canvas.get_tk_widget().grid(row=0,column=1)
canvas.show()
self.plotbutton=tk.Button(master=root, text="plot", command=lambda: self.plot(canvas,ax))
self.plotbutton.grid(row=0,column=0)
def plot(self,canvas,ax):
c = ['r','b','g'] # plot marker colors
ax.clear() # clear axes from previous plot
for i in range(3):
theta = np.random.uniform(0,360,10)
r = np.random.uniform(0,1,10)
ax.plot(theta,r,linestyle="None",marker='o', color=c[i])
canvas.draw()
root=tk.Tk()
app=Application(master=root)
app.mainloop()
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