Hi, I'm in the middle of porting LSQR (iterative solver for unsymmetric systems) to Commons-Math. I need to be able to define a "transposable" real linear operator. In other words, on top of RealVector RealLinearOperator.operate(RealVector), I also need a method which would read RealVector RealLinearOperator.operateTranspose(RealVector).
My problem is: how to do that? 1. Extend RealLinearOperator? That would allow for compile time checks. The problem is I've already defined InvertibleRealLinearOperator. So how about operators which are both invertible and transposable? 2. Create an interface, say Transposable? But then, no compile time check can be performed in LSQR.RealVector solve(RealLinearOperator a, RealVector b) (defined in AbstractIterativeLinearSolver). The only thing I can do is test whether the specified operator implements the interface Transposable. 3. Add the method operateTranspose to RealLinearOperator, and allow for UnsupportedOperationException. I could then add a method boolean isTransposable() to RealLinearOperator. Again, no compile-time check is possible. Do you have any thoughts? Sébastien --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@commons.apache.org For additional commands, e-mail: dev-h...@commons.apache.org
