Python: How to find the slope of a graph drawn using matplotlib?

Question

Here is my code:

import matplotlib.pyplot as plt
plt.loglog(length,time,'--')

where length and time are lists.

How do I find the slope of this graph?

Answer 1

If you have matplotlib then you must also have numpy installed since it is a dependency. Therefore, you could use numpy.polyfit to find the slope:

import matplotlib.pyplot as plt
import numpy as np

length = np.random.random(10)
length.sort()
time = np.random.random(10)
time.sort()
slope, intercept = np.polyfit(np.log(length), np.log(time), 1)
print(slope)
plt.loglog(length, time, '--')
plt.show()