Question

Purpose:

Learn to use arrays.

Instructions:

This is a project you will work on with a group of 3 (or 4) students.

Groups of 3 will already have a left and right partner.

Your assignment is to learn how to create code for others to use and how to use other people's code in your own project. Working with others is often a challenge especially when you haven't worked with them previously. If you know one of your partners from outside the class, you'll need to choose a different partner.

You will create a function that calculates the "Sample Standard Deviation" on an array of N ints where the value of N is 25 - strlen(your middle name). If you don't have a middle name, strlen will return 0.

You will need to create an array of random int values you will place into an array in code. DO NOT enter the values through std::cin.

You will give your function to your right partner and your data to your left partner.

Likewise, you will receive data from your right partner and a function from your left partner.

Your function should be placed in .cpp file by itself and include a .h (header) file with the function declaration.

You should now have 2 sets of data and 2 functions.

Run all 4 combinations in one program and test that the Sample Standard Deviation functions both produce the same results for the same data set. This means you will have 2 tests, one for each set of data.

You should compare your results with your partners. They should produce the same results. If not, work out why.

Proper submission is extremely important, so be sure to look over the guidelines.

For help with formulas, here is a site that might help you:

https://www.mathsisfun.com/data/standard-deviation-formulas.html

Answer 1

declarations.h

double getStandardDeviation(int array[], int size); void getRandomNumbersArray(int array[], int size); void printArray(int array[], int size);

SampleStd.cpp

#include<iostream> #include<cstdlib> #include<ctime> #include<string.h> #include<cmath> #include"declarations.h" using namespace std; // main function int main() { srand(time(NULL)); // seeding the random number generator char middleName[50]; cout << "Enter your middle name: "; // inputting the middle name fgets(middleName, 50, stdin); int size = 25 - strlen(middleName); // deciding the size of array int array[size]; getRandomNumbersArray(array, size); // calling the function to populate the array cout << "\nArray generated is." << endl; printArray(array, size); cout << endl; double std = getStandardDeviation(array, size); // calculating the std cout << endl; cout << "Sample Standard Deviation is: " << std << endl; } // function to calculate and return the standard deviation double getStandardDeviation(int array[], int size) { double mean = 0; int sum = 0; double squared_diff = 0; for(int i = 0; i < size; i++) sum += array[i]; mean = sum / size; for(int i = 0; i < size; i++) { squared_diff += pow((array[i] - mean), 2); } squared_diff /= size - 1; return sqrt(squared_diff); } // function to populate the arrray with random numbers void getRandomNumbersArray(int array[], int size) { for(int i = 0; i < size; i++) { // generating a random number in range -10 to 100 array[i] = -10 + (rand() * (int)(100 - -10) / RAND_MAX); } } // printing the array void printArray(int array[], int size) { for(int i = 0; i < size; i++) cout << array[i] << " "; }

NOTE: Create a header file named declarations.h and another file SampleStd.cpp and copy - paste its respective codes into it and save. Now, run the main file SampleStd.cpp

OUTPUT

E:\Program Files Cplusplus workspace SampleStd.exe nter your middle name: william rray generated is 4 74 48 44 8 94 13 17 29 73 57 52 53 1 81 38 75 ample Standard Deviation is: 27.4829 Process exited after 10.49 seconds with return value 0 ress any key to continue -. .