Template class and class properties, which are also templates

Question

I am having trouble compiling the following header. This is my first experience with templates, and I assume that something is wrong with me. Compilers indicate errors in vector<vector<T>> data_;and the operator overload function. I would like the vector to data_have the same type as the object OptBaseMatrix, but I'm not sure how to do this ... I really don't know how to solve this problem. Help!

#ifndef OPTBASEMATRIX_H
#define OPTBASEMATRIX_H

#include <vector>

template<typename T>
class OptBaseMatrix 
{ 
public:
 vector<vector<T>> data_; 

 OptBaseMatrix(int rows, int cols);
 ~OptBaseMatrix();

 void readMatrix();
 void printMatrix();
 int getRows();
 int getCols();

    OptBaseMatrix<T> operator+(const OptBaseMatrix<T>& matrix1, const OptBaseMatrix<T>& matrix2);

private:
 int rows_; 
 int cols_; 
};

#endif // OPTBASEMATRIX_H

The UPDATE . Here is a snippet from the debug log:

Error   1   error C2143: syntax error : missing ';' before '<'  optbasematrix.h 17  TD2
Error   2   error C4430: missing type specifier - int assumed. Note: C++ does not support default-int   optbasematrix.h 17  TD2

I tried changing the vector> data_; by vector> data_; and still get the same error: / I read somewhere that my template class header (.h) and implementation (.cpp) should be in the same file ... is this possibly related?

2: ! "using namespace std;". !

Answer 1

>.

 vector<vector<T> > data_;

>> -/ .

, operator+ :

// Member function
Matrix<T> operator+(const Matrix<T>& other) const;

// Free function (`friend` makes the function free
// even though it declared within the scope of the class definition)
friend Matrix<T> operator+(const Matrix<T>& lhs, const Matrix<T>& rhs);

Answer 2

Try:

vector<vector<T> > data_;