'''
    DS2000
    Spring 2023 
    Sample code from class - 
    1. writing our own functions
    2. calling functions
'''

import random
import matplotlib.pyplot as plt

def max_list(lst):
    ''' Function: max_list
        Parameters: list of non-negative numbers
        Returns: a number
        Does: finds and returns the max value in the list
    '''
    # this would cause an error, no "mylst" in max_list
    # print(mylst)
    curr_max = -1
    for num in lst:
        if num > curr_max:
            curr_max = num
    return curr_max

    # The line below will never happen :(
    # "return" both returns the result and ends the function
    print("Function is over")
    
def plot_list(lst):
    ''' Function: plot list
        Parameters: list of numbers
        Returns: nothing!
        Does: Plot the values in the list
    '''
    plt.plot(lst)
    plt.xlabel("position")
    plt.ylabel("random value")
    plt.title("Randomly generated numbers")
   
def main():
    # Gather data - generate a list of random numbers
    mylst = [random.randint(0, 50) for i in range(50)]
    # this would cause an error, no "lst" in main
    # print(lst)
    
    # Computation - find the max by calling the max function
    max_value = max_list(mylst)
    
    # Communication - print out the original list and the max we found
    # and call the plot function to plot the list
    print(mylst)
    print("Max value is:", max_value)
    plot_list(mylst)
    
main()