Displaying plot in Tkinter GUI frame - python-3.x

Question

I want to show the plot canvas in the top right side of UI (using Tkinter python3). I wrote the following code but I got the following error:
canvas = FigureCanvasTkAgg(fig, master=root) NameError: name 'root' is not defined
My code is:
import tkinter as tk
import tkinter.ttk as ttk
from tkinter import *
import matplotlib.pyplot as plt
from matplotlib.backends.backend_tkagg import FigureCanvasTkAgg, NavigationToolbar2Tk
from matplotlib.figure import Figure
import sys
class GUI(tk.Frame):
def __init__(self, master = None):
self.root = tk.Tk()
self.root.geometry("500x500")
tk.Frame.__init__(self, master)
self.createWidgets()
def start(self):
self.root.mainloop()
def createWidgets(self):
fig = plt.figure(figsize=(8, 8))
canvas = FigureCanvasTkAgg(fig, master=root)
canvas.get_tk_widget().grid(row=0, column=1)
canvas.show()
def main():
appstart = GUI()
appstart.start()
if __name__ == "__main__":
main()

Answer 1

I made some changes to your code, deleting some unnecessary
references such as:
import tkinter.ttk as ttk
from tkinter import *
from matplotlib.figure import Figure
import sys
self.root = tk.Tk()
tk.Frame.__init__(self, master)
that you dont' use and I think only confuse yourself.
I've even simplified your script and add this code below to show to you wath is "self"
print(type(self))
for item in dir(self):
print(type(item),item)
I've add even a toolbar to the plot and some data to plot something.
Regards
import tkinter as tk
import matplotlib.pyplot as plt
from matplotlib.backends.backend_tkagg import FigureCanvasTkAgg, NavigationToolbar2Tk
import numpy as np
class GUI(tk.Tk):
def __init__(self):
super().__init__()
self.title("Hello World")
self.geometry("500x500")
self.createWidgets()
print(type(self))
for item in dir(self):
print(type(item),item)
def createWidgets(self):
t = np.arange(0, 3, .01)
f0 = tk.Frame()
fig = plt.figure(figsize=(8, 8))
fig.add_subplot(111).plot(t, 2 * np.sin(2 * np.pi * t))
canvas = FigureCanvasTkAgg(fig, f0)
toolbar = NavigationToolbar2Tk(canvas, f0)
toolbar.update()
canvas._tkcanvas.pack(fill=tk.BOTH, expand=1)
f0.pack(fill=tk.BOTH, expand=1)
def main():
appstart = GUI()
appstart.mainloop()
if __name__ == "__main__":
main()

Answer 2

In your code you should use self.root if your intent is to use the root window:
canvas = FigureCanvasTkAgg(fig, master=self.root)
... or maybe just self, if your intent is to have it appear inside the frame. I'm not entirely sure what you are intending to do
canvas = FigureCanvasTkAgg(fig, master=self)
Somewhat unrelated, if you're explicitly creating a root window, you should be passing that to tk.Frame.__init__ rather than master.
tk.Frame.__init__(self, self.root)