xkcd "Hand drawn" plot

xkcd-plot.py

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

import matplotlib.pyplot as plt
from math import pi as pi
import numpy as np
import scipy.ndimage as ndimage


def distortPlot(y):
  yOffset = y + y.max() / 100 * np.random.randn(len(y))
  yOffSmoothed = ndimage.gaussian_filter(yOffset, sigma=1.75, order=0)
  
  return yOffSmoothed

x = np.arange(0, 2 * pi, 0.05)
y = np.sin(x)
yp = np.cos(x)
fig = plt.figure()
ax = fig.add_subplot(111)
font = {'family': 'Comic Sans MS',
        'weight': 'bold',
        'size': 14}
linwidth = 3

xsin = distortPlot(x)
ysin = distortPlot(y)

xcos = xsin
ycos = distortPlot(yp)

horline = np.zeros(len(x)) + np.random.randn(len(x)) * .01
ax.plot(x, distortPlot(horline), lw=linwidth, color='black')

ax.plot(xsin, ysin, lw=linwidth * 3, color='white')
ax.plot(xsin, ysin, lw=linwidth)
ax.plot(xcos, ycos, lw=linwidth * 3, color='white')
ax.plot(xcos, ycos, lw=linwidth)
ax.axis([-0.1, (2 * pi) - 0.075, -1.05, 1.05])
ax.spines['bottom'].set_linewidth(0)
ax.spines['right'].set_color('none')
ax.spines['bottom'].set_position('center')
ax.spines['top'].set_color('none')
ax.spines['left'].set_linewidth(0)
ax.spines['left'].set_smart_bounds(True)
ax.spines['bottom'].set_smart_bounds(True)
ax.xaxis.set_ticks_position('bottom')
ax.yaxis.set_ticks_position('left')
ax.tick_params(axis='both', direction='in', width=3, length=10, pad=8)

verty = np.arange(ysin.min() - 0.05, ysin.max() + 0.05, 0.05)
vertline = np.zeros(len(verty)) + np.random.randn(len(verty)) * .05
ax.plot(distortPlot(vertline), verty, lw=linwidth, color='black')

ax.annotate('NICE CURVE', xy=(xsin[50], ysin[50]),  xycoords='data',
            xytext=(50, 30), textcoords='offset points',
            arrowprops=dict(arrowstyle="->",
                            lw=3,
                            connectionstyle="arc,angleA=180,armA=70,rad=20"),
            )

plt.rc('font', **font)
plt.show()