CSSE 120 -- Intro. to Software Development

Homework 25

Take a look at the Python vs C comparison document. You may find this helpful as you try to do things in C that you already know how to do in Python. Feel free to suggest things that we might add to this document.
There is no Angel quiz for the next session.
Using Eclipse, checkout the HousePrices project from your individual SVN repository into your Eclipse C workspace. This will require connecting to the repository using the SVN Repository Exploring perspective. Within that project, open the file main.c, which contains a template for the rest of this assignment. Add your name and the date you start solving the problems to the initial comments and commit your work to your repository.
Problem we wish to solve:
Point your browser to http://www.trulia.com/home_prices/Indiana/.

Click on the Vigo County link on the Indiana map, then on the link for "Homes for sale in Vigo County". Make sure the "Homes for sale" checkbox is checked on the page that appears in your browser window.

You should see a a list of homes for sale that you can sort by address, price, type, beds, baths or broker. Sort by beds. You should see several pages of listings (with up to 15 listings on each page).

For this exercise we are interested in using arrays to help us study the prices of 4 bedroom houses. In particular, we would like to know the
1. average (mean) price,
2. median price,
3. 5 highest prices, and
4. 5 lowest prices
of 4 bedroom homes in Vigo county. We will guide you in helping us to do this study by giving you a template to follow.
Fill in the code for function swap(). swap() takes the addresses of two variables that are of type double and swap their values. Test the swap function by allowing the main() function to invoke the testSwap() function. testSwap() simply shows whether the swap function works.
After testing and debugging this function, commit your work to your Subversion repository. Do this by right-clicking on your HousePrices project in Eclipse and choosing Team → Commit.... Be sure to enter in a sensible log message as the course staff may review the messages.
Fill in the code for function sort(). sort() takes an array and its size, and sorts it in increasing order. Test the sort function by invoking it in the main() function and using the printArray() function to see that the houses array is sorted. After testing and debugging this function, commit your work to your Subversion repository.
Fill in the code for function findMean. findMean() takes an array and its size, and returns the mean of the values in the array. Test the findMean function by invoking it in the main() function and printing its value. Your results should be formatted as shown below.
```
The mean value of the array is x.
```
After testing and debugging this function, commit your work to your Subversion repository using a sensible log message.
Fill in the code for function findMedian. findMedian() takes an array and its size, and returns the median of the values in the array. Test the findMedian function by invoking it in the main() function and printing its value. Your results should be formatted as shown below
```
The median value of the array is x.
```
After testing and debugging this function, commit your work to your Subversion repository using a sensible log message.
Fill in the code for function printNHighestPrices(). printNHighestPrices() takes an array, its size, and an int n as parameters and print a message with the n highest values in the array. Test the printNHighestPrices function by invoking it in the main() function. Your results should be formatted as shown below
```
The n highest values in order are x1, x2, ..., xn. 
```
After testing and debugging this function, commit your work to your Subversion repository using a sensible log message.
Repeat question 9 for function printNLowestPrices().

In function main() delete the statement used to initialize the houses array and fill the array with the prices from the website referenced in question 4. Rather than typing all those values, you can just copy and paste the following prices for 4 bedroom homes that were current on Oct. 29:

double houses[71] = {129500.0, 129900.0, 138900.0, 159900.0, 
    44900.0, 490000.0, 89500.0, 34000.0, 82000.0, 219900.0,
    47500.0, 144900.0, 159999.0, 99900.0, 166900.0, 229900.0,
    240000.0, 89900.0, 299900.0, 49900.0, 585000.0, 275000.0,
    209900.0, 259900.0, 269900.0, 389900.0, 86500.0, 99900.0,
    79900.0, 175000.0, 54900.0, 139900.0, 129900.0, 34900.0,
    119900.0, 257700.0, 149900.0, 139900.0, 149900.0, 174900.0,
    145900.0, 189900.0, 212900.0, 48900.0, 75900.0, 330000.0,
    17500.0, 235000.0, 449900.0, 179900.0, 119900.0, 147000.0,
    155000.0, 239000.0, 219900.0, 309000.0, 131900.0, 345000.0,
    165000.0, 299900.0, 45000.0, 230000.0, 99500.0, 83500.0,
    156900.0, 289900.0, 45900.0, 185500.0, 19000.0, 124000.0,
    159900.0};

Change the value of numberOfHomes in the line above the array initialization to 71. Using the functions you have implemented and tested above, have your program provide the information requested in question 4. Your output should be formatted as follows (substituting the actual values, of course):

The mean price of 4 bedroom houses in Vigo County is $12345.67.
The median price of 4 bedroom houses in Vigo County is $12345.67.
The 5 most expensive 4 bedroom houses in Vigo County cost $12345.67, $12345.67, $12345.67, $12345.67, and $12345.67.
The 5 least expensive 4 bedroom houses in Vigo County cost $12345.67, $12345.67, $12345.67, $12345.67, and $12345.67.

Submit your code by committing the final version to your Subversion repository.