matrix

[ssaa391]

creat class have
*if two columns can be different sizes.
*the object can be resize.
*the object check if the user refers to an element that is out of range
*provide different matrix-oriented operation

class myarray{
  private:
	 int p[3][3];
	int p2[100];
  public:
	 void diffrentsize(){
	int x;
	int y;
	int z;
	int w;
	cout<<"enter 4 size of array"<<endl;
  cin>>x;
  cin>>y;
  cin>>z;
  cin>>w;
  int *p4[4];
  p4[0]=new int[x];
  p4[1]=new int[y];
  p4[2]=new int[z];
  p4[3]=new int[w];
	  }
	  void setarray(vector<int> p[3][3],vector<int> p2[100]){
		  p[3][3]=p[3][3];
		  p2[100]=p2[100];
	  }
	  int getp(){
		  return p[3][3];
	  }
	  	  void size()
	  {
	int *arr;
	int size;
   int* resize_arr = new int[size + 1];
   for(int i = 0; i < size; i++)
        resize_arr[i] = arr[i];

   size++;
   arr = resize_arr;
   delete[] resize_arr;
	  }
         void check(vector<int> p2 ) {
          if(p2.length()>100){
          cout<<"the length of array is bigger than size of array"<<endl;
          }
		  else 
		  {cout<<"the length of array is fit the size of array"<<endl;}
		  }
  void det(vector<int> p[3][3]){
  cout<<endl<<"TO FIND DETERMINANT"<<endl;
	int n = 0,val;
	cout<<"enter no. of columns/rows of square matrix"<<endl;
	cin>>n;
	int **p3;
	p3 = new int*[n]; //make an array of ints, p points to them
	for (int i = 0; i< n; i++) 
	{
		p3[i] = new int[n]; //each pointer now points to 'n' amount of ints

	}
	int a  = 0;
	for (int i = 0; i < n; i++)
	{
		for (int j = 0; j < n; j++)
		{
			p3[i][j] = a++; //assign some values
		}
	}
	cout<<"enter the values of matrix row-wise"<<endl;
	for (int i = 0; i < n; i++)
	{
		for (int j = 0; j < n; j++)
		{
			cin>>p3[i][j];
			if (n==1)
				val=p3[i][j];
		}
	}
        //using the formulae
	if (n==2)
	{val=p3[0][0]*p3[1][1]-p3[0][1]*p3[1][0];}
	if (n==3)
		{val=(p3[0][0]*((p3[1][1]*p3[2][2])-(p3[1][2]*p3[2][1])))-
		    (p3[0][1]*((p3[1][0]*p3[2][2])-(p3[1][2]*p3[2][0])))+
			(p3[0][2]*((p3[1][0]*p3[2][1])-(p3[1][1]*p3[2][0])));}
        for (int i = 0; i < 3; i++)
	{
		delete((int*)p[i]);//free up the array of pointers, must delete each one otherwise memory will leak

	}
	delete [] p;
	cout<<"determinant value is:";
	cout<<val<<endl;
	
}
void transpose(vector<int> p[3][3]){
	int n = 0,m=0;
	cout<<"TO FIND TRANSPOSE"<<endl;
	cout<<"enter no. of rows and columns of matrix"<<endl;
	cin>>m>>n;
	int **p3;
	p3 = new int*[m];
	for (int i = 0; i< m; i++)
	{
		p3[i] = new int[n];
	}
	int a  = 0;
	for (int i = 0; i < m; i++)
	{
		for (int j = 0; j < n; j++)
		{
			p3[i][j] = a++;
		}
	}
	cout<<"enter the numbers of matrix row-wise"<<endl;
	for (int i = 0; i < m; i++) //input values
	{
		for (int j = 0; j < n; j++)
		{
			cin>>p3[i][j];
		}
	}
	cout<<"matrix you have entered is"<<endl;
	for (int i = 0; i < m; i++) //output matrix entered
	{
		for (int j = 0; j < n; j++)
		{
			cout << p3[i][j] << "\t";
		}
		cout << "\n";
	}
	int **q;
	q = new int*[m];
	cout<<endl;
	for (int i = 0; i< m; i++) //create the matrix(to be transpose)
	{
		q[i] = new int[n];
	}
	a  = 0;
	for (int i = 0; i < m; i++)
	{
		for (int j = 0; j < n; j++)
		{
			q[i][j] = a++;
		}
	}
	for (int i = 0; i < n; i++)//assigning corresponding values to make a transpose
	{
		for (int j = 0; j < m; j++)
		{
			q[i][j] = p3[j][i];
		}
	}
	cout<<"transpose is"<<endl;
	for (int i = 0; i < n; i++) //output transpose
	{
		for (int j = 0; j < m; j++)
		{
			cout << q[i][j] << "\t";
		}
		cout << "\n";
	}
	for (int i = 0; i < m; i++)
	{
		delete((int*)q[i]);
	}
	delete [] q;
	
}
void add(vector<int> p[3][3]){
	int n = 0,m=0;
	cout<<"TO FIND THE SUM"<<endl;
	cout<<"enter no. of rows and columns of matrix"<<endl;
	cin>>m>>n;
	int **t,**q;
	t = new int*[m];
	for (int i = 0; i< m; i++)
	{
		t[i] = new int[n];
	}
	int a  = 0;
	for (int i = 0; i < m; i++)
	{
		for (int j = 0; j < n; j++)
		{
			t[i][j] = 0;
		}
	}
	char chk='y'; //any number of matrices can be added
	while (chk=='y'||chk=='Y'){
		q = new int*[m];
		for (int i = 0; i< m; i++)
		{
			q[i] = new int[n];
		}
		a  = 0;
		for (int i = 0; i < m; i++)
		{
			for (int j = 0; j < n; j++)
			{
				q[i][j] = a++;
			}
		}
		cout<<"enter the numbers of matrix to be added"<<endl;
		for (int i = 0; i < m; i++)
		{
			for (int j = 0; j < n; j++)
			{
				cin>>q[i][j];
			}
		}
		cout<<"matrix you have entered"<<endl;
		for (int i = 0; i < m; i++)
		{
			for (int j = 0; j < n; j++)
			{
				cout << q[i][j] << "\t";
			}
			cout << "\n";
		}
		for (int i = 0; i < m; i++) //addition
		{
			for (int j = 0; j < n; j++)
			{
				t[i][j] = t[i][j]+q[i][j];
			}
		}
		for (int i = 0; i < m; i++)
		{
			delete((int*)q[i]);
		}
		delete [] q;
		cout<<"wish to add another matrix to this? y/n"<<endl;
		cin>>chk;
	}
	cout<<"sum is "<<endl;
	for (int i = 0; i < m; i++) //output sum
	{
		for (int j = 0; j < n; j++)
		{
			cout << t[i][j] << "\t";
		}
		cout << "\n";
	}
	for (int i = 0; i < m; i++)
	{
		delete((int*)t[i]);
	}
	delete [] t;
	
}
void subtract(vector <int> p[3][3]){
	cout<<"TO SUBTRACT"<<endl;
	int n = 0,m=0;
	cout<<"enter no. of rows and columns of matrix"<<endl;
	cin>>m>>n;
	int **t,**q;
	char chk;
	t = new int*[m];
	for (int i = 0; i< m; i++)
	{
		t[i] = new int[n];
	}
	int a  = 0;
	for (int i = 0; i < m; i++)
	{
		for (int j = 0; j < n; j++)
		{
			t[i][j] = 0;
		}
	}
	cout<<"enter the numbers of matrix"<<endl;
	for (int i = 0; i < m; i++)
	{
		for (int j = 0; j < n; j++)
		{
			cin>>t[i][j];
		}
	}
	cout<<"matrix you have entered"<<endl;
	for (int i = 0; i < m; i++)
	{
		for (int j = 0; j < n; j++)
		{
			cout << t[i][j] << "\t";
		}
		cout << "\n";
	}
	chk='y';
	while (chk=='y'||chk=='Y'){
		q = new int*[n];
		for (int i = 0; i< m; i++)
		{
			q[i] = new int[n];
		}
		a  = 0;
		for (int i = 0; i < m; i++)
		{
			for (int j = 0; j < n; j++)
			{
				q[i][j] = a++;
			}
		}
		cout<<"enter the numbers of matrix to be subtracted"<<endl;
		for (int i = 0; i < m; i++)
		{
			for (int j = 0; j < n; j++)
			{
				cin>>q[i][j];
			}
		}
		cout<<"matrix you have entered"<<endl;
		for (int i = 0; i < m; i++)
		{
			for (int j = 0; j < n; j++)
			{
				cout << q[i][j] << "\t";
			}
			cout << "\n";
		}
		for (int i = 0; i < m; i++)
		{
			for (int j = 0; j < n; j++)
			{
				t[i][j] = t[i][j]-q[i][j];
			}
		}
		for (int i = 0; i < m; i++)
		{
			delete((int*)q[i]);
		}
		delete [] q;
		cout<<"wish to subtract another matrix from the result? y/n"<<endl;
		cin>>chk;
	}
	cout<<"difference is "<<endl;
	for (int i = 0; i < m; i++)
	{
		for (int j = 0; j < n; j++)
		{
			cout << t[i][j] << "\t";
		}
		cout << "\n";
	}
	for (int i = 0; i < n; i++)
	{
		delete((int*)t[i]);
	}
	delete [] t;
	
}
void multiply(vector<int> p[3][3]){
	int n = 0,m=0,l=0;
	cout<<"TO FIND THE PRODUCT"<<endl;
	cout<<"enter no. of rows and columns of matrix"<<endl;
	cin>>m>>n;
	int **t,**q;
	t = new int*[m];
	for (int i = 0; i< m; i++)
	{
		t[i] = new int[n];
	}
	int a  = 0;
	for (int i = 0; i < m; i++)
	{
		for (int j = 0; j < n; j++)
		{
			t[i][j] = 0;
		}
	}
	cout<<"enter the numbers of matrix "<<endl;
	for (int i = 0; i < m; i++)
	{
		for (int j = 0; j < n; j++)
		{
			cin>>t[i][j];
		}
	}
	cout<<"matrix you have entered"<<endl;
	for (int i = 0; i < m; i++)
	{
		for (int j = 0; j < n; j++)
		{
			cout << t[i][j] << "\t";
		}
		cout << "\n";
	}
	cout<<"enter no. of columns of 2nd matrix"<<endl;//no.of rows of 2nd column=no.of columns of 1st matrix(rule)
	cin>>l;
	q = new int*[n];
	for (int i = 0; i< n; i++)
	{
		q[i] = new int[l];
	}
	a  = 0;
	for (int i = 0; i < n; i++)
	{
		for (int j = 0; j < l; j++)
		{
			q[i][j] = a++;
		}
	}
	cout<<"enter the numbers of matrix to be multiplied"<<endl;
	for (int i = 0; i < n; i++)
	{
		for (int j = 0; j < l; j++)
		{
			cin>>q[i][j];
		}
	}
	cout<<"matrix you have entered"<<endl;
	for (int i = 0; i < n; i++)
	{
		for (int j = 0; j < l; j++)
		{
			cout << q[i][j] << "\t";
		}
		cout << "\n";
	}
	cout<<"product is"<<endl;
	int k=0;
	for (int i=0;i<m;i++)
	{
		for (int j=0;j<l;j++)
		{
			for (int r=1;r<=n;r++)
			{
				k=k+(t[i][r-1]*q[r-1][j]);
			}
			cout<<k<<"\t";
			k=0;
		}
		cout<<endl;
	}
	
}

void post(vector <int>p[3][3]){
	int po[3][3];
	int x=1;
	for (int i=0;i<3;i++){
	for(int j=0;j<3;j++){
		cin>>po[i][j];
		if(po[i][j]*-1==-po[i][j]||po[i][j]*-1==po[i][j]){
			x*=po[i][j];}
	}
	}
	cout<<"the check if matrix is positive-definite "<<endl;
	if (x=='-'){
		cout<<"negitive"<<endl;}
	else {cout<<"positive"<<endl;}
}
};

[therockon7throw]

O man! who has taught you C++, who has taught you to code in that way ? It is terrible, and awful.

[jmadsen]

Ok, therockon7throw was right. That is ugly. That looks like FORTRAN. Word to the wise, you won't get many responses with code looking like that. Explain what you are trying to do better than just giving a bunch of code with minimal comments.

Listen -- AVOID hardcoded numbers! This is a computer program not pencil and paper. Especially since you want to resize things. And learn what a vector is. It is a dynamically allocating array. You don't want to have a function parameter that takes a vector argument like std::vector<int> p[3][3]. Hell, I am not even sure if that is valid bc I cant begin to understand what you are trying to accomplish there.

So for what you first wrote:
creat class have
*if two columns can be different sizes.

*the object can be resize.

poor english but I am guessing this means you want a vector. Use the push_back() function to add on to the end, or clear() and resize() if you want to start from scratch.


*the object check if the user refers to an element that is out of range

You want a try catch exception for this.
in other words:

#include <stdexcept>
#include <iostream>
#include <exception>
#include <vector>

int main(int argc, char* argv[]) 
{
   std::vector myVector;
   myVector.resize(5,0); // initialize vector to ndim = 5, value = 0
   myVector.push_back(1); // resize the vector to ndim = 6 with myVector[5] = 1

   int someNumber = 8;
   try {
      myVector.at(someNumber);
   } catch (std::out_of_range const &ex) {
      std::cout << "Exception: " << ex.what() << " -- "<< someNumber 
      << " is out of the allowed range" << std::endl;
   }

}

*provide different matrix-oriented operation

with vectors you can access this sort of information with size()
in other words:

unsigned int ndim = 10; // 10x10 square matrix

// notice no hard coded numbers except for ndim which wouldn't
// really exist because you should be passing "second" to the function 
// and returning transpose

std::vector<double> first;
std::vector<std::vector<double> > second;
first.resize(ndim,0);   // initialize all ten rows to zero
second.resize(ndim,first); // initialize ten columns of zero from first

int num = 1;
// second is 10x10 square matrix, transpose will also be 10x10
// try using this function, add in code to print out second and transpose
std::vector<std::vector<double> > transpose = second;
// transpose the matrix, notice no h
for(unsigned int i = 0; i < second.size(); ++i) {
   for(unsigned int j = 0; j < second[i].size(); ++j) {
      second[i][j] = num;
      transpose[j][i] = second[i][j];
      ++num;
   }
}