======Part 3======

=====Entries=====

===November 7th, 2011====
Worked through some Array programs that we made in Structured Orientation and Problem Solving.
====November 15th, 2011====
started
// Purpose:   A simple program demonstrating the use of pointers.

#include <iostream>
using namespace std;

int main()
{
	// declare an integer and a float variable
	int IntNum; 
	float FloatNum;
	
	// declare integer and float pointers
	int *pIntNum;
	float *pFloatNum;
	
	// initialize the integer and float variables
	IntNum = 10;
	FloatNum = 12.34;
	
	// store addresses in pointers
	pIntNum = &IntNum;
	pFloatNum = &FloatNum;


====November 16th, 2011====
	// print out the original values
        cout << "Before increment: " << endl;
	cout << "\t IntNum is: " << IntNum << endl;
	cout << "\t FloatNum is: " << FloatNum << endl;
	
	// note that we need to dereference a pointer in order
	// to extract the value it contains.
	cout << "\t pIntNum contains: " << *pIntNum << endl;
	cout << "\t pFloatNum contains: " << *pFloatNum << endl;

	// increment values of the integer and float variables 
	(*pIntNum)++;  // dereference and then increment
	(*pFloatNum)++;

	// print out the values after increment
        cout << "After increment: " << endl;
	cout << "\t IntNum is: " << IntNum << endl;
	cout << "\t FloatNum is: " << FloatNum << endl;

	cout << "\t pIntNum contains: " << *pIntNum << endl;
	cout << "\t pFloatNum contains: " << *pFloatNum << endl;

	return 0;
}


====November 29, 2011====
Worked on Opus, studied the point program a little bit (used example from a website that guided me through the process)
=====cprog Topics=====

====Function Overloading====
You overload a function name f by declaring more than one function with the name f in the same scope.

<code c>
#include <iostream>
using namespace std;

void print(int i) {
  cout << " Here is int " << i << endl;
}
void print(double  f) {
  cout << " Here is float " << f << endl;
}

void print(char* c) {
  cout << " Here is char* " << c << endl;
}

int main() {
  print(10);
  print(10.10);
  print("ten");
}
</code>

====Command-line arguments====
In C++ it is possible to accept command line arguments. Command-line arguments are given after the name of a program in command-line operating systems like DOS or Linux, and are passed in to the program from the operating system.

<code>
int main ( int argc, char *argv[] )
</code>

====“this” pointer====
The type of the this pointer for a member function of a class type X, is X* const. If the member function is declared with the const qualifier, the type of the this pointer for that member function for class X, is const X* const

<code c>
struct A {
  int a;
  int f() const { return a++; }
};
</code>

====Inheritance====
Inheritance is a mechanism of reusing and extending existing classes without modifying them, thus producing hierarchical relationships between them.


====Polymorphism====
Polymorphism is the ability for objects of different classes related by inheritance to respond differently to the same member function call


====Operator overloading====
Operator overloading is a special kind of Polymorphism which is defined by the programmer or the program itself. 


====Exception Handing====
Exceptions provide a way to react to exceptional circumstances (like runtime errors) in our program by transferring control to special functions called handlers.

<code c>
// exceptions
#include <iostream>
using namespace std;

int main () {
  try
  {
    throw 20;
  }
  catch (int e)
  {
    cout << "An exception occurred. Exception Nr. " << e << endl;
  }
  return 0;
}
</code>

====Abstract Base Class====
An abstract class is a class that is designed to be specifically used as a base class

<cli>
class AB {
public:
  virtual void f() = 0;
};
</cli>


====Standard Template Library====
Standard Template Library; it provides many of the basic algorithms and data structures of computer science

<code c>
vector<int> v(3);            // Declare a vector of 3 elements.
      v[0] = 7;
      v[1] = v[0] + 3;
      v[2] = v[0] + v[1];          // v[0] == 7, v[1] == 10, v[2] == 17 
</code>


====Templates====
Function templates are special functions that can operate with generic types

<code c>
template <class myType>
myType GetMax (myType a, myType b) {
 return (a>b?a:b);
}
</code>






=====cprog Objective=====
====Objective====
know the difference between structures and classes

===Analysis===
Reflect upon your results of the measurement to ascertain your achievement of the particular course objective.

The class is the template or plate of a program or code, while the structure is sort of like the meat and potatoes of a programs, they're both important to a program, but both very unique to one another.
=====Experiments=====
====Experiment 1====

===Question===
What will happen if you do not declare a variable in a pointer program?

===Resources===
Using google I collected a guide to making a pointer program with undefined variables.

===Hypothesis===
The program will not run because the variables are undefined and the program will not know what to do.

===Experiment===
Using the program,

<code>

#include <iostream>
using namespace std;

int main()
{
	// declare an integer and a float variable
	int IntNum; 
	float FloatNum;
	
	// declare integer and float pointers
	int *pIntNum;
	float *pFloatNum;
	
	// initialize the integer and float variables
	IntNum = 10;
	FloatNum = 12.34;
	
	// store addresses in pointers
	pIntNum = &IntNum;
	pFloatNum = &FloatNum;

	// print out the original values
        cout << "Before increment: " << endl;
	cout << "\t IntNum is: " << IntNum << endl;
	cout << "\t FloatNum is: " << FloatNum << endl;
	
	// note that we need to dereference a pointer in order
	// to extract the value it contains.
	cout << "\t pIntNum contains: " << *pIntNum << endl;
	cout << "\t pFloatNum contains: " << *pFloatNum << endl;

	// increment values of the integer and float variables 
	(*pIntNum)++;  // dereference and then increment
	(*pFloatNum)++;

	// print out the values after increment
        cout << "After increment: " << endl;
	cout << "\t IntNum is: " << IntNum << endl;
	cout << "\t FloatNum is: " << FloatNum << endl;

	cout << "\t pIntNum contains: " << *pIntNum << endl;
	cout << "\t pFloatNum contains: " << *pFloatNum << endl;

	return 0;
}
</code>

===Data===
The program was put into Putty and compiled. The program did not run, it gave the following results, 
./pointer.c: In function 'main':
./pointer.c:26: error: 'cout' undeclared (first use in this function)
./pointer.c:26: error: (Each undeclared identifier is reported only once
./pointer.c:26: error: for each function it appears in.)
./pointer.c:26: error: 'endl' undeclared (first use in this function)

===Analysis===
Based on the data collected:

  * was your hypothesis correct? Yes
  * is there more going on than you originally thought? (shortcomings in hypothesis)There are multiple variables in this program which need to be defined for the program to run, however I do believe that even if one or two variable were defined, it would still not run because there's over 8 variables alone.
  * what shortcomings might there be in your experiment? Coding may be incorrect
  * what shortcomings might there be in your data? Unsure.

===Conclusions===
Variables need to be defined in any program you write in order to operate properly