This repository has been archived on 2021-05-17. You can view files and clone it, but cannot push or open issues or pull requests.
scientificComputing/regression/lecture/lin_regress.py

64 lines
1.8 KiB
Python

import numpy as np
import matplotlib.pyplot as plt
from plotstyle import *
def create_data():
m = 0.75
n= -40
x = np.arange(10.,110., 2.5)
y = m * x + n;
rng = np.random.RandomState(37281)
noise = rng.randn(len(x))*15
y += noise
return x, y, m, n
def plot_data(ax, x, y):
ax.scatter(x, y, marker='o', color=colors['blue'], s=40)
show_spines(ax, 'lb')
ax.set_xlabel('Input x')
ax.set_ylabel('Output y')
ax.set_xlim(0, 120)
ax.set_ylim(-80, 80)
ax.set_xticks(np.arange(0,121, 40))
ax.set_yticks(np.arange(-80,81, 40))
def plot_data_slopes(ax, x, y, m, n):
ax.scatter(x, y, marker='o', color=colors['blue'], s=40)
xx = np.asarray([2, 118])
for i in np.linspace(0.3*m, 2.0*m, 5):
ax.plot(xx, i*xx+n, color=colors['red'], lw=2)
show_spines(ax, 'lb')
ax.set_xlabel('Input x')
#ax.set_ylabel('Output y')
ax.set_xlim(0, 120)
ax.set_ylim(-80, 80)
ax.set_xticks(np.arange(0,121, 40))
ax.set_yticks(np.arange(-80,81, 40))
def plot_data_intercepts(ax, x, y, m, n):
ax.scatter(x, y, marker='o', color=colors['blue'], s=40)
xx = np.asarray([2, 118])
for i in np.linspace(n-1*n, n+1*n, 5):
ax.plot(xx, m*xx + i, color=colors['red'], lw=2)
show_spines(ax, 'lb')
ax.set_xlabel('Input x')
#ax.set_ylabel('Output y')
ax.set_xlim(0, 120)
ax.set_ylim(-80, 80)
ax.set_xticks(np.arange(0,121, 40))
ax.set_yticks(np.arange(-80,81, 40))
if __name__ == "__main__":
x, y, m, n = create_data()
fig, axs = plt.subplots(1, 3)
fig.subplots_adjust(wspace=0.5, **adjust_fs(fig, left=6.0, right=1.5))
plot_data(axs[0], x, y)
plot_data_slopes(axs[1], x, y, m, n)
plot_data_intercepts(axs[2], x, y, m, n)
fig.savefig("lin_regress.pdf")
plt.close()