def show_activation(activation, y_lim=5):
x_array = np.arange(-10.0, 10.0, 0.01)
x = tf.Variable(x_array)
y = activation(x)
with tf.Session() as sess:
sess.run(tf.global_variables_initializer())
y_ = sess.run(y)
ax = plt.gca()
ax.spines['right'].set_color('none')
ax.spines['top'].set_color('none')
ax.spines['bottom'].set_position(('data', 0))
ax.spines['left'].set_position(('data', 0))
ax.xaxis.set_ticks_position('bottom')
ax.yaxis.set_ticks_position('left')
lines = plt.plot(x_array, y_)
plt.setp(lines, color='b', linewidth=2.0)
plt.ylim(y_lim * -1 - 0.1, y_lim + 0.1)
plt.xlim(-10, 10)
plt.show()