extrema_fig_1d.ipynb

Kernel: Unknown Kernel

# Plot local minimum and maximum in 1d

# https://nbviewer.jupyter.org/github/entiretydotai/Meetup-Content/blob/master/Neural_Network/7_Optimizers.ipynb


import numpy as np
import scipy.sparse
import matplotlib.pyplot as plt
import os
from matplotlib import colors as mcolors

try:
    import probml_utils as pml
except ModuleNotFoundError:
    %pip install -qq git+https://github.com/probml/probml-utils.git
    import probml_utils as pml


def f(x):
    return x * np.sin(-np.pi * x)


a = np.arange(-1, 3, 0.01)
plt.annotate("local minimum", xy=(0.7, -0.55), xytext=(0.1, -2.0), arrowprops=dict(facecolor="black"))

plt.annotate("Global minimum", xy=(2.5, -2.5), xytext=(0.1, -2.5), arrowprops=dict(facecolor="black"))

plt.plot(a, f(a))
pml.savefig("extrema_fig_1d.pdf")
plt.show()