Código de Python - Graficador de funciones

#!/usr/bin/env python

# -*- coding: utf-8 -*-

import tkinter

from matplotlib.figure import Figure

from matplotlib.backends.backend_tkagg import FigureCanvasTkAgg, NavigationToolbar2Tk

from matplotlib import style

import matplotlib.animation as animation

import matplotlib.pyplot as plt

import numpy as np

from tkinter import messagebox

from math import *

root = tkinter.Tk()

root.wm_title("Graficador")

ta=root.geometry("1000x700")

style.use('fivethirtyeight')

fig = Figure()

ax1 = fig.add_subplot(111)

canvas = FigureCanvasTkAgg(fig, master=root)  # CREAR AREA DE DIBUJO DE TKINTER.

canvas.draw()

canvas.get_tk_widget().pack(side=tkinter.TOP, fill=tkinter.BOTH, expand=1)

toolbar = NavigationToolbar2Tk(canvas, root)# barra de iconos

toolbar.update()

canvas.get_tk_widget().pack(side=tkinter.TOP, fill=tkinter.BOTH, expand=1)

act_rango=False

ul_ran=""

ran=""

def animate(i):

    global act_rango

    global ul_ran

    if act_rango==True:

        try:

            lmin = float(ran[0]); lmax = float(ran[1])

            if lmin < lmax:

                x = np.arange(lmin, lmax, .01)#.01

                ul_ran = [lmin, lmax]

            else:

                act_rango = False

        except:

            messagebox.showwarning("Error","Introduzca los valores del rango de x, separado por coma.")

            act_rango=False

            ets.delete(0,len(ets.get()))

    else:

        if ul_ran!="":

            x = np.arange(ul_ran[0],ul_ran[1], .01)#.01

        else:

            x = np.arange(1, 10, .01)#.01

    try:

        solo=eval(graph_data)

        ax1.clear()

        ax1.plot(x,solo)

    except:

        ax1.plot()

    ax1.axhline(0, color="gray")

    ax1.axvline(0, color="gray")

    ani.event_source.stop() #DETIENE ANIMACIÓN

def represent():

    global graph_data

    global ran

    global act_rango

    texto_orig=et.get()

    if ets.get()!="":

        rann=ets.get()

        ran=rann.split(",")

        act_rango=True

    ta=texto_orig.replace("sin","np.sin")

    tb=ta.replace("cos","np.cos")

    tl=tb.replace("log","np.log")

    tc=tl.replace("tan","np.tan")

    tr=tc.replace("sqrt","np.sqrt")

    graph_data=tr

    ani.event_source.start() #INICIA/REANUDA ANIMACIÓN

ani = animation.FuncAnimation(fig, animate, interval=1000)

plt.show()

et = tkinter.Entry(master=root,width=60)

et.config(bg="gray87", justify="left")

button = tkinter.Button(master=root, text="SET", bg="gray69", command=represent)

button.pack(side=tkinter.BOTTOM)

et.pack(side=tkinter.BOTTOM)

ets=tkinter.Entry(master=root,width=20)

ets.config(bg="gray87")

ets.pack(side=tkinter.RIGHT)

#ets.insert(0,"RANGO DE X")

tkinter.mainloop()