API that handles boost ublas sparse OR dense matrices

I am a bit perplexed by the Boost ublas documentation. It does not seem clear to me that the sparse and dense matrix classes share a common parent class---which I believe is by design. But then how can I design an API that can accept either sparse开发者_StackOverflow or dense matrix, assuming that it need only operate on entries of the matrix using the operator() accessor, say. For example, something like this:

float doMatrixMath(matrix_base<float> m) 
{
  return m(1,1)+m(2,2);
}

Perhaps my thinking about this is wrong-headed. Any guidance regarding how to think about the object modeling of ublas classes would be appreciated!

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Templates unfortunately. You can use a very generic type, or dig in and find something more concrete, but the general idea is:

template< typename MatrixType >
float doMatrixMath(MatrixType m) 
{
  return m(1,1)+m(2,2);
}

Of course this can be enhanced with a more concrete type and return value detection...