plot.py

#!/usr/bin/env python3

import numpy as np
import matplotlib.pyplot as plt
import matplotlib.animation as animation
import os
import sys

fig = plt.figure()

def f(x):
    return pow(2, -10 * x**2) + x**3

min_x = -1.0
max_x = 1.0
x_point = 0.5
width = 0.2

x = np.arange(min_x, max_x, 0.01)
y = f(x)

x2 = np.arange(x_point-0.1, x_point+0.1, 0.01)
y2 = f(x2)

graph_color = 'blue'

def make_frame(label):
    ax = plt.axes(label=label)
    ax.set_title(label)
    ax.plot(x, y, alpha=0)
    return ax

def fileName(number):
    return "continuous{}.png".format(number)


def generate_frame0():
    ax = make_frame("Take an arbitrary function")
    ax.plot(x, y, color=graph_color)
    plt.savefig(fileName(0))

def generate_frame1():
    ax = make_frame("Its infinitely small fragment")
    ax.plot(x, y, alpha=0)
    ax.plot(x2, y2, color=graph_color)
    plt.savefig(fileName(1))

def generate_frame2():
    ax = make_frame("Topological transformation\nto have infinitely small width")
    ax.plot(x, y, alpha=0)
    ax.fill_between(x2, y2-width/2, y2+width/2, color=graph_color)
    plt.savefig(fileName(2))

def generate_frame3():
    ax = make_frame("...does not differ of")
    ax.plot(x, y, alpha=0)
    ax.fill_between(x2, [f(x_point)-width/2 for t in x2], [f(x_point)+width/2 for t in x2], color=graph_color)
    plt.savefig(fileName(3))

def generate_frame4():
    ax = make_frame("Shift to infinitely many x positions.\nThis set is the generalized limit")
    ax.plot(x, y, alpha=0)
    for i in range(6):
        ax.fill_between(x2 + (i-4)*0.3, [f(x_point)-width/2 for t in x2], [f(x_point)+width/2 for t in x2], color=graph_color)
    plt.savefig(fileName(4))

def generate_frame5():
    ax = make_frame("Its y limit point is the customary limit")
    ax.plot(x, y, alpha=0)
    for i in range(6):
        ax.fill_between(x2 + (i-4)*0.3, [f(x_point)-width/2 for t in x2], [f(x_point)+width/2 for t in x2], color=graph_color)
    ax.plot(x, [f(x_point) for t in x], color='red')
    plt.savefig(fileName(5))

def generate_frame(number):
    h = [generate_frame0, generate_frame1, generate_frame2, generate_frame3, generate_frame4, generate_frame5]
    h[number]()

# if os.system("convert -delay 200 -loop 0 frame*.png plot.gif"):
#     raise "Cannot execute `convert`."

# if os.system("rm -f frame*.png"):
#     raise "Cannot remove temp files."

ids = (int(x) for x in sys.argv[1:])
for id in ids:
    generate_frame(id)