24 lines
426 B
Python
24 lines
426 B
Python
"""
|
|
sigmoid
|
|
~~~~~~~
|
|
|
|
Plots a graph of the sigmoid function."""
|
|
|
|
import numpy
|
|
import matplotlib.pyplot as plt
|
|
|
|
z = numpy.arange(-5, 5, .1)
|
|
sigma_fn = numpy.vectorize(lambda z: 1/(1+numpy.exp(-z)))
|
|
sigma = sigma_fn(z)
|
|
|
|
fig = plt.figure()
|
|
ax = fig.add_subplot(111)
|
|
ax.plot(z, sigma)
|
|
ax.set_ylim([-0.5, 1.5])
|
|
ax.set_xlim([-5,5])
|
|
ax.grid(True)
|
|
ax.set_xlabel('z')
|
|
ax.set_title('sigmoid function')
|
|
|
|
plt.show()
|