"""
ECE 09351 - Digital Signal Processing
Lab 1 Question 1

Translated from MATLAB by Aidan Sharpe
Last Modified: January 16, 2025
"""


import numpy as np
import matplotlib.pyplot as plt



def main():
    f_s = 100                   # Sample frequency [Hz]
    T_s = 1/f_s                 # Sample period [s]

    n = np.arange(10)           # Samples starting at zero, up to, but not including 10
    t = n*T_s                   # Convert from sample domain to time domain

    x_20 = np.cos(2*np.pi*20*t) # Cosine signal x[n] with f = 20[Hz]
    x_80 = np.cos(2*np.pi*80*t) # Cosine signal x[n] with f = 80[Hz]

    plt.subplot(211)            # Begin top subplot
    plt.stem(n, x_20)           # Plot samples of x (x_20) over sample indicies (n)
    plt.subplot(212)            # Begin bottom subplot
    plt.stem(n, x_80)           # Plot samples of x (x_80) over sample indicies (n)

    plt.show()                  # Show the plot



if __name__ == "__main__":
    main()