How to return class from that class' member function?

[forlorn]

Hi,
i'm trying to write a simple matrix class. I want to a add a function that transpozes the matrix and returns the transpozed one.

CMatrix CMatrix::Transpose()
{
CMatrix mat;
int temp;

temp = m_ROW;
m_ROW = m_COL;
m_COL = temp;

(A) mat = new CMatrix( m_ROW, m_COL );

// etc.

return mat;
}

Compiler tells me that "operator =" function is unavailable.( For line labeled with (A) )

Do i have to define functions for all operators?

And also what is a "copy constructor"? VC++ complains about lacking one of them.

By the way, if you happen to know about a simple matrix class, would you please tell me where to find it.

Thanks a lot.

 

[programsecrets]

A question to lead you to the answer:

When you allocate an object, do you assign it to an object... or to a pointer? Once you've answered that, then also think about what data type you want to return from the member function.

 

[tchouch]

Right:
CMatrix CMatrix::Transpose()
{
CMatrix *mat;
int temp;

temp = m_ROW;
m_ROW = m_COL;
m_COL = temp;

(A) mat = new CMatrix( m_ROW, m_COL );

// etc.

return *mat;
}
or so:
CMatrix *CMatrix::Transpose()
{
CMatrix *mat;
int temp;

temp = m_ROW;
m_ROW = m_COL;
m_COL = temp;

(A) mat = new CMatrix( m_ROW, m_COL );

// etc.

return mat;
}
Do not forget to use delete after new!
To define operator "=", You can define copy constructor
CMatrix::CMatrix(CMatrix matr)
{
...
}

 

[forlorn]

Thanks to both of you. I think jumping directly into C++ from Java without fully understanding pointers was a mistake. But it's getting better by your help.
Thanks again.