Question

This is an exercise to design and write a Python program in good programming style for a simulation of stock price over a period of 100 days. In this exercise, you are asked to simulate the stock price starting at $100.00 for 100 days with a daily fluctuation based on the Normal Distribution with mean = 0.0 & sigma = 0.0125. The program will show the daily stock price, the 7-day minimum, the 7-day maximum, the 7-day average, and the 50-day average. The program should also give an indication of "***" when the stock price drops beyond the 50-day average!

Some More Notes & Hints for Assignment #1

1. Make use of the random module to simulate the fluctuation of stock price.

Here is the function and codes for simulating the changes in the stock prices:

import random

random.seed(37) # I like to set the random seed at 37!

def fluctuation():

    return (random.normalvariate(0.0, 0.0125))

…

StockPrice = 100.0 # StockPrice starts at $100.00

…

for i in range(100):

    StockPrice *= (1 + fluctuation()) # Calculate the next StockPrice

    Print(StockPrice)

2. Use a list StockHistory to keep track of the stock prices. Starting with an empty list, append to the end of the list the stock price of the day. Keep appending the stock price to the list until the length of the list is greater than 50. You can then delete the first item from the list and keep the list just to contain the last 50 records of the stock prices. And thus, you can calculate the 50-Day Average for the stock.

StockHistory = [] # Start with an empty list

…

StockHistory.append(StockPrice) # To append StockPrice to the end of the list

…

If (len(StockHistory) > 50): # If the list contains more than 50 records,

    StockHistory.pop(0)      # delete the first record which is indexed by zero

…

# Calculate the 50-Day Average here

3. Here is the suggested flow of the program:

• Construct the Program Header with program name, author’s name, program description, … etc
• Import the module(s) needed
• Define the function(s) needed
• Set the random seed by simply adding “random.seed(37)” into the program
• Setup the global variable(s) with their initial value(s)
• Print the “Table Header”
• For the next 100 days do the followings:
  • Calculate the StockPrice according to the random fluctuation
  • Print the Number of Days and the current StockPrice
  • Append the StockPrice to the StockHistory list
  • The list should contain up to 50 records, delete the first record if necessary
  • Print out the 7-Day Min, Max, and Average if you have 7 or more records
  • Print out the 50-Day Average if you have reached and maintained at 50 records
  • Print out the indication of “***” if the StockPrice drops below the 50-Day Average

Sample Run:

Day Price   7DayMin 7DayMax 7DayAve 50DayAve

===========================================================

   1 100.430    N/A     N/A     N/A    N/A: 1 record only!

   2 102.035    N/A     N/A     N/A    N/A: 2 record only!

   3 103.544    N/A     N/A     N/A    N/A: 3 record only!

   4 104.005    N/A     N/A     N/A    N/A: 4 record only!

   5 104.075    N/A     N/A     N/A    N/A: 5 record only!

   6 105.098    N/A     N/A     N/A    N/A: 6 record only!

   7 104.307 100.430 105.098 103.356 N/A: 7 record only!

   8 105.257 102.035 105.257 104.046 N/A: 8 record only!

   9 103.909 103.544 105.257 104.314 N/A: 9 record only!

10 102.860 102.860 105.257 104.216 N/A: 10 record only!

11 104.508 102.860 105.257 104.288 N/A: 11 record only!

12 105.239 102.860 105.257 104.454 N/A: 12 record only!

13 103.018 102.860 105.257 104.157 N/A: 13 record only!

14 101.931 101.931 105.257 103.817 N/A: 14 record only!

15 102.110 101.931 105.239 103.368 N/A: 15 record only!

16 101.724 101.724 105.239 103.056 N/A: 16 record only!

17 104.617 101.724 105.239 103.307 N/A: 17 record only!

18 105.754 101.724 105.754 103.485 N/A: 18 record only!

19 107.406 101.724 107.406 103.794 N/A: 19 record only!

20 107.700 101.724 107.700 104.463 N/A: 20 record only!

21 108.102 101.724 108.102 105.345 N/A: 21 record only!

22 109.072 101.724 109.072 106.339 N/A: 22 record only!

23 107.316 104.617 109.072 107.138 N/A: 23 record only!

24 105.429 105.429 109.072 107.254 N/A: 24 record only!

25 105.558 105.429 109.072 107.226 N/A: 25 record only!

26 105.927 105.429 109.072 107.015 N/A: 26 record only!

27 106.443 105.429 109.072 106.835 N/A: 27 record only!

28 106.460 105.429 109.072 106.601 N/A: 28 record only!

29 106.592 105.429 107.316 106.246 N/A: 29 record only!

30 106.976 105.429 106.976 106.198 N/A: 30 record only!

31 106.377 105.558 106.976 106.333 N/A: 31 record only!

32 107.154 105.927 107.154 106.561 N/A: 32 record only!

33 107.715 106.377 107.715 106.817 N/A: 33 record only!

34 107.870 106.377 107.870 107.021 N/A: 34 record only!

35 108.851 106.377 108.851 107.362 N/A: 35 record only!

36 108.319 106.377 108.851 107.609 N/A: 36 record only!

37 110.846 106.377 110.846 108.162 N/A: 37 record only!

38 110.038 107.154 110.846 108.685 N/A: 38 record only!

39 112.567 107.715 112.567 109.458 N/A: 39 record only!

40 111.409 107.870 112.567 109.986 N/A: 40 record only!

41 111.210 108.319 112.567 110.463 N/A: 41 record only!

42 112.808 108.319 112.808 111.028 N/A: 42 record only!

43 114.457 110.038 114.457 111.905 N/A: 43 record only!

44 112.541 110.038 114.457 112.147 N/A: 44 record only!

45 113.414 111.210 114.457 112.630 N/A: 45 record only!

46 110.535 110.535 114.457 112.339 N/A: 46 record only!

47 113.114 110.535 114.457 112.583 N/A: 47 record only!

48 110.396 110.396 114.457 112.467 N/A: 48 record only!

49 109.363 109.363 114.457 111.974 N/A: 49 record only!

50 108.904 108.904 113.414 111.181 107.106

51 107.142 107.142 113.414 110.410 107.240 ***

52 107.967 107.142 113.114 109.632 107.359

53 109.558 107.142 113.114 109.492 107.479

54 107.356 107.142 110.396 108.669 107.546 ***

55 108.697 107.142 109.558 108.427 107.638

56 106.906 106.906 109.558 108.076 107.675 ***

57 108.727 106.906 109.558 108.050 107.763

58 108.526 106.906 109.558 108.248 107.828

59 106.926 106.906 109.558 108.099 107.889 ***

60 106.773 106.773 108.727 107.702 107.967 ***

61 107.399 106.773 108.727 107.708 108.025 ***

62 106.325 106.325 108.727 107.369 108.046 ***

63 105.409 105.409 108.727 107.155 108.094 ***

64 103.058 103.058 108.526 106.345 108.117 ***

65 104.850 103.058 107.399 105.820 108.172 ***

66 105.534 103.058 107.399 105.621 108.248 ***

67 105.582 103.058 107.399 105.451 108.267 ***

68 105.656 103.058 106.325 105.202 108.265 ***

69 105.801 103.058 105.801 105.127 108.233 ***

70 105.770 103.058 105.801 105.179 108.195 ***

71 106.881 104.850 106.881 105.725 108.170 ***

72 108.815 105.534 108.815 106.291 108.165

73 109.718 105.582 109.718 106.889 108.213

74 109.935 105.656 109.935 107.511 108.303

75 111.708 105.770 111.708 108.376 108.426

76 110.394 105.770 111.708 109.032 108.515

77 110.657 106.881 111.708 109.730 108.600

78 108.628 108.628 111.708 109.979 108.643 ***

79 108.190 108.190 111.708 109.890 108.675 ***

80 107.816 107.816 111.708 109.618 108.692 ***

81 108.890 107.816 111.708 109.469 108.742

82 107.755 107.755 110.657 108.904 108.754 ***

83 107.756 107.755 110.657 108.528 108.755 ***

84 107.046 107.046 108.890 108.012 108.739 ***

85 109.494 107.046 109.494 108.135 108.751

86 108.003 107.046 109.494 108.109 108.745 ***

87 107.984 107.046 109.494 108.133 108.688 ***

88 107.121 107.046 109.494 107.880 108.629 ***

89 108.025 107.046 109.494 107.918 108.539 ***

90 107.489 107.046 109.494 107.880 108.460 ***

91 107.331 107.121 109.494 107.921 108.383 ***

92 110.167 107.121 110.167 108.017 108.330

93 108.463 107.121 110.167 108.083 108.210

94 106.691 106.691 110.167 107.898 108.093 ***

95 103.771 103.771 110.167 107.420 107.900 ***

96 104.179 103.771 110.167 106.870 107.773 ***

97 106.573 103.771 110.167 106.739 107.642 ***

98 108.709 103.771 110.167 106.936 107.608

99 106.547 103.771 108.709 106.419 107.552 ***

100 104.034 103.771 108.709 105.786 107.455 ***

Answer 1

Functions and global variables are defined as per the question and you can test run the below code to obtain the answer.  

import random
random.seed(37) # I like to set the random seed at 37!
mean = 0.0
sigma = 0.0125

def fluctuation():
    return (random.normalvariate(mean, sigma))

def get_day_average(arr,day):
    if len(arr)<day:
        return "N/A: {0} record only!".format(len(arr))
    else:
        total=0
        for i in range(day):
            total += arr[len(arr)-(i+1)]
        return total/day

def get_day_min(arr,day):
    if len(arr)<day:
        return "N/A"
    else:
        return min(arr[-day:])

def get_day_max(arr,day):
    if len(arr)<day:
        return "N/A"
    else:
        return max(arr[-day:])

def print_header(): 
    print("Day      Price     7DayMin 7DayMax        7DayAve         50DayAve")
    print("======================================================================")

StockPrice = 100.0 # StockPrice starts at $100.00
StockHistory = [] # Start with an empty list

print_header()
for day in range(1,101):
    StockPrice *= (1 + fluctuation()) # Calculate the next StockPrice
    
    
    if not type(get_day_average(StockHistory,50)) == str and StockPrice < get_day_average(StockHistory,50):
        indicator="***"
    else:
        indicator = ""

    print(day,StockPrice,get_day_min(StockHistory,7),get_day_max(StockHistory,7),get_day_average(StockHistory,7),get_day_average(StockHistory,50),indicator)

    
    StockHistory.append(StockPrice) # To append StockPrice to the end of the list
    if (len(StockHistory) > 50): # If the list contains more than 50 records,
        StockHistory.pop(0)      # delete the first record which is indexed by zero