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pythonmatplotlibmathsignals

How to plot multiple periods using pyplot?

everyone!

I'm learning about signals now, but I'm having a tough time trying to plot more than one period using pyplot. I don't know if the problem is with the mathematical part or with the code itself. I think this is a silly question, but any help would be great!

import numpy as np
import matplotlib.pyplot as plt


def function(t):
    return t**2


# Fundamental Period and Frequency:
T = 2*np.pi
w = 2*np.pi/T

# Defining the limits and the x values(in our case, time):
inferior_limit, superior_limit = -np.pi, np.pi
time_values = np.linspace(inferior_limit, superior_limit, 1000)

# Desired function plot:
plt.style.use('bmh')
plt.plot(time_values, function(time_values), color='k')
plt.show()

This is what is begin plot: enter image description here

And this is what I would like to plot: enter image description here

Solution

  • The main problem here is that t² is not a periodic function. The graph of the function you want is (((t + π) % (2π)) - π)² (graph).

    You can implement that in the function function as:

    def function(t):
    return (((t + np.pi) % (2*np.pi)) - np.pi)**2

    Just changing that should give the output: signal