Is it possible to predefine a subrange or project with a specific range so that when called I only had to pass in the matrix?  I'm currently dealing with several 9x9 matrices that I need to access the 3x3 submatrix (topleft, topmiddle, topright, etc.).  Is there a way to typedef or templatize a subrange or project so that I just need to pass the 9x9 matrix and get the topleft matrix?

 

Example:

 

typedef subrange(input_matrix, 0, 3, 0, 3) topleft;  //This is what I want to somehow define.

 

matrix<double> A(9,9);

topleft(A) = zero_matrix<double>(3,3);

 

Ryan