Java Statistics

Topic

Primitive Arrays

Description

Write a program that will compute a number of statistics for a set of data provided by the user. The data will be made up of decimal numbers. After inputting the data, the program will compute and display the following statistics relating to the data.

• Min Value
• Max Value
• Mean Value
• Median Value

Implementation

Do the above assignment by creating two classes: Statistics and TestStatistics.

The class Statistics will be used as a blue print for a Statistics object.

It will keep a set of data and will provide methods for computing statistics relating to the data. The data will be provided to the Statistics object in an array during object construction.

The class TestStatistics will be used to hold the method main. The method main will be used to input the data, create the Statistics object, compute statistics by calling Statistics object methods and display the values received.

Class Statistics

The class Statistics will provide the following:

• A private array variable data for holding user data.
• A private array variable sdata for holding a sorted copy of the above data.
• A constructor to initialize the array data.
• A method getOrigData for returning a copy of the array data.
• A method getSortedData for returning a copy of the original array but now sorted.
• A method findMin for computing min
• A method findMax for computing max
• A method findMean for computing mean (or average)
• A method findMedian for computing median

Class TestStatistics

The class TestStatistics will provide the method main which will do the following:

• Prompt the user for the number of total items in the data.
• Create an array of that size.
• Input data items from the user and store them in the array.
• Create an object of the class Statistics and pass it the data array.
• Call a Statistics object method to obtain the original data array.
• Call a Statistics object method to obtain the data array but now sorted in ascending order.
• Call Statistics object methods for calculating the min, max, mean and median values.
• Display the original data, data sorted in ascending order, min, max, mean and median values.

Testing

Test Run:

Input

(User input is shown in bold).

Enter the Number Of Data Values: 12
Enter Data Value: 7.2
Enter Data Value: 7.6
Enter Data Value: 5.1
Enter Data Value: 4.2
Enter Data Value: 2.8
Enter Data Value: 0.9
Enter Data Value: 0.8
Enter Data Value: 0.0
Enter Data Value: 0.4
Enter Data Value: 1.6
Enter Data Value: 3.2
Enter Data Value: 6.4

Output

Original Data:
7.2 7.6 5.1 4.2 2.8 0.9 0.8 0.0 0.4 1.6 3.2 6.4
Sorted Data:
0.0 0.4 0.8 0.9 1.6 2.8 3.2 4.2 5.1 6.4 7.2 7.6
Min Value: 0.0
Max Value: 7.6
Mean: 3.35
Median: 3.0