The goal of this lab is to gain more comfort with C++ functions
and arrays. We will practice using arrays to process a list of numbers
in various ways. A skeleton version the program will appear in your
cs35/lab/1 directory when you run update35. The
program handin35 will only submit files in this directory. In
later labs you can work with a partner, but for this lab you should
work on your own.
For this lab you will prompt the user to enter a series of integers in a given range. Then you will perform some statistical analyses on the data and report the results. The most common statistical measure is the mean, which is simply the average. Another useful measure is the standard deviation, which provides an indication of how much the individual values in the data differ from the mean. A small standard deviation indicates that the data is tightly clustered. A large standard deviation indicates that the data is widespread. Finally, a histogram is a graphical way of summarizing the data by dividing it into separate ranges and then indicating how many data values fall into each range. Here is a sample run of a program that performs these three statistical analyses:
This program calculates statistics on a set of given data. It calculates the mean, standard deviation, and prints a histogram of the values. Enter integers in the range 0-100 to be stored, -1 to end. > 90 > 89 > 97 > 95 > 123 Invalid value, try again. > 84 > 71 > 78 > 88 > 82 > 100 > 55 > -1 Read in 11 valid values. Mean: 84.455 Standard deviation: 12.324 Histogram: 0 - 9: 10 - 19: 20 - 29: 30 - 39: 40 - 49: 50 - 59: * 60 - 69: 70 - 79: ** 80 - 89: **** 90 - 99: *** 100 - 100: *
int getIntegerArray(int data, int capacity, int min, int max, int sentinel);This function will read integers into the data array, which can hold at most capacity values. The values must be between min and max. The user will enter the sentinel value to quit. This function will return the number of valid values read in.
float mean(int data, int n);that returns the average of the values stored in the data array whose effective size is n.
float standardDeviation(int data, int n)that retuns the standard deviation of the values stored in the data array whose effective size is n. In order to calculate the standard deviation, perform the following steps:
void histogram(int data, int n, int min, int max, int binSize);Notice that the return type of this function is void. This indicates that a function does not return any value. In this case the function prints information on the screen rather than returning a value. The parameters of this function include the data array, its effective size n, the smallest and largest possible values stored in the array, and the size of each bin. The number of asterisks in a particular row indicates the number of values in the data that fall into each designated range. You will need to use printf rather than cout to format the output appropriately. In the sample run shown above, the bin size was 10. However, you should not assume that the bin size will always be 10. Shown below is the same set of data used in the sample run, but with a binSize of 7.
Histogram: 0 - 6: 7 - 13: 14 - 20: 21 - 27: 28 - 34: 35 - 41: 42 - 48: 49 - 55: * 56 - 62: 63 - 69: 70 - 76: * 77 - 83: ** 84 - 90: **** 91 - 97: ** 98 - 100: *Notice that the last bin will often be a different size than the all the other bins.