CS 2510 Assignment 3 Dr. Woelfl

The purpose of this assignment is to write a C++ program which will produce a text graph of data given in polar form. This program will use the Point class developed in lab 4.

Using the program written in class and working in teams of 2 or 3, make the following revisions:

• Add member variable c which is the character to be used for a point in the character plot.

• Add member function polarToRect() which will compute the rectangular x and y values given the polar form.

• Add a function that prompts for, opens a file, reads in Point data from a file, and closes the file. The function prototype is (notice number of points is pass by reference):

void dataIn(Point*, int& number_points);

• Add function scale that will shift the origin so that all x and y values are positive and normalize the values between zero and one. The prototype is (notice number of points is pass by value):

void scale(Point*, int number_of_points);

Example values for scaling are shown in the table:

Original x y values	Shifted Origin	Scaled
-5 5	0 15	0.00 0.75
5 10	10 20	0.50 1.00
0 -10	5 0	0.25 0.00

• Adjust the aspect-ratio for y which will yield a properly proportioned plot (this is just a scaling factor for y values). Start with a value of about 0.5 and adjust it up or down to yield a square plot for the printer you are using (create a test file with a “square”).

• Open two output files, one that will have the character plot of the data and second that will have the x and y values of the data before any scaling (ignore the character and use markers only) as two columns. Import the second data file into Excel and plot the data. Import the data into Microsoft Excel using menu items:

Data, Get External Data, Import Text File, for delimiters, check space and check treat consecutive delimiters as one

If the file was formatted properly, your data will appear in two columns of the spreadsheet. Simply highlight all the data and choose a chart of type x-y (Scatter) no lines, only markers. The first column, which should be x values, will be used for the x axis. Label and format the graph for black and white copying (no colors!).

Create a test input data file having data in polar form: magnitude, angle in degrees, and character and use it to develop your program. Actual files for the assignment will be on the website soon. A copy of your source code and two plots are due on Friday of week seven.