C++

Forum

 
Mean median and mode problem

shannonhos (5)
Write your question here.
I can't figure out how to get the mode
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
 

// This program calculates stats of movie goers in a month
//It calculates mean, median and mode
#include <iostream>
#include <iomanip>

using namespace std;

double calculateMean(int *, int);
double calculateMedian(int *, int);
int calculateMode(int *, int);

int main()
{
	int *nums;		
	int num_students;	
	char repeat = ' ';	

	do
	{

	cout << "Enter in how many students were surveyed: ";
	cin >> num_students;

	while (num_students < 0)
	{
		cout << "Invalid number of students. Enter a positive integer.\n";
		cout << "Enter in how many students were surveyed: ";
		cin >> num_students;
	}
	nums = new int[num_students];


	for (int count = 0; count < num_students; count++)
	{
		cout << "Number of movies viewed by Person #" << (count + 1) << ": ";
		cin >> nums[count];

		while (nums[count] < 0)
		{
			cout << "Please enter in a positive number: ";
			cout << "\nNumber of movies viewed by Person #" << (count + 1) << ": ";
			cin >> nums[count];
		}

	}

	cout << fixed << showpoint << setprecision(1);

	cout << "\nThe mean is: ";
	cout << calculateMean(nums, num_students) << endl;

	cout << "\nThe median is: ";
	cout << calculateMedian(nums, num_students) << endl;

	cout << "\nThe mode is: ";
	cout << calculateMode(nums, num_students) << endl;
	
	delete[] nums;
	nums = 0;		

	cout << "Do you want to try again? ";
	cin >> repeat;

	
	} while (repeat == 'Y' || repeat == 'y');
	cout << "Program ending.\n";
	
	return 0;
}

double calculateMean(int *nums, int num_students)
{
	double total = 0;
	double average;

	for (int count = 0; count < num_students; count++)
	{
		total += nums[count];
	}
	average = total / num_students;
return average;
}

double calculateMedian(int *nums,  int num_students)
{
	double median = 0.0;
	cout << fixed << showpoint << setprecision(1);

	
	if (num_students % 2 == 0)
	{
		median = (nums[num_students / 2] + nums[(num_students / 2) + 1]) / 2.0;
	
	}
	else
		median = nums[num_students / 2];

	return median;
}

int calculateMode(int *nums, int num_students)
{
	int mode = 0;
	int val = 0;
	int index;
	
	for (index = 0; index < num_students; index++)
	{
		if (*(nums + index) == *(nums + (index + 1)))
		{
			mode++;
			val = *(nums + index);
		}
	}
		if (val > 0)
			return val;
		else
			return -1;

	}

  Put the code you need help with here.
keskiverto (10402)
According to:
http://www.purplemath.com/modules/meanmode.htm

Your median needs a bit more too.

For mode, you have to think pairs; a value and how many times it occurs. You should have one pair for each unique value. A set like {2,5,3,3,7,2,5} is multi-modal, because 2, 3, and 5 each occur twice, and therefore the set has not one, but three modes.
Topic archived. No new replies allowed.