Matrix template functions are listed here.
 ptrreader<M> | Create an instance of mtx_ptrreader | 
 flatreader<M> | Create an instance of mtx_flatreader | 
 ptrwriter<M> | Create an instance of mtx_ptrwriter | 
 flatwriter<M> | Create an instance of mtx_flatwriter | 
 copy_offset<M, N> | Copy one matrix to another, with offsets, truncating if required | 
 mtx_copy<M, N> | Copy one matrix to another, resizing if required | 
 mtx_flatten<M, V> | Copy the members of a matrix to a flattened vector | 
 mtx_copy_transpose<M, N> | Copy one matrix to another, with the contents transposed | 
 mtx_transpose<M> | Transpose the rows and columns of a matrix |