I wrote about this the other day but do not think I explained it too clearly...I shall try again...
So my problem is this...when I am trying to allocate memory to a pointer, it fails.
This is my MatrixClass definition..
class MatrixClass
{
public:
MatrixClass(int m, int n);
MatrixClass(void);
virtual ~MatrixClass(void);
double getRead(int num1, int num2) const;
double& getReadWrite(int num3, int num4);
void set(int i,int j,double value);//set value at i,j to value
MatrixClass(const MatrixClass &rhs);
void assign(int M,int N);
MatrixClass sum1(const MatrixClass& rhs) const;
MatrixClass operator+(const MatrixClass& rhs);//overloading the + operator
inline MatrixClass operator-();
private:
double* dataptr;
int M;
int N;
};
I am trying to do this..
MatrixClass BB;
BB = A + B;
So here is my overloaded + function..
MatrixClass MatrixClass::operator +(const MatrixClass &rhs)
{
MatrixClass temp;
//temp.M = this->M + rhs.M;
//temp.N = this->N + rhs.N;
for(int i = 0;i < M;i++)
{
for(int j = 0; j<N;j++)
{
temp.dataptr[i * N + j] = this->getReadWrite(i,j) + rhs.dataptr[i*N+j];
}
}
return temp;
}//end operator +
Once temp returns...it calls the copy constructor...passing temp as 'rhs' and 'this' would refer to 'BB'? (Am I right in thinking this?)
MatrixClass::MatrixClass(const MatrixClass &rhs)//copy constructor
{
this->M = rhs.M;
this->N = rhs.N;
dataptr = 0;
if(rhs.dataptr != 0)
{
dataptr = new double[M * N];//allocate memory for the new object being assigned to...
the line here where I try to allocate memory gives me an error.....Am I right in thinking that this would be assigning memory to dataptr of 'BB'?? Values are assigned to 'M' and 'N' fine....
int num = sizeof(double);
memcpy(this->dataptr,rhs.dataptr,M*N*sizeof(double));
}
else
{
this->dataptr = 0;
}
}//end copy constructor
Also the error that i get is this... 'Unhandled exception at 0x75a0b727 in assignment.exe: Microsoft C++ exception: std::bad_alloc at memory location 0x002af924..'
Hope someone can help me...I am at a massive loss with this...thanks!