orthog.h

 
//
// orthog.h -- orthogonalize the basis set
//
// Copyright (C) 1996 Limit Point Systems, Inc.
//
// Author: Curtis Janssen <cljanss@ca.sandia.gov>
// Maintainer: LPS
//
// This file is part of the SC Toolkit.
//
// The SC Toolkit is free software; you can redistribute it and/or modify
// it under the terms of the GNU Library General Public License as published by
// the Free Software Foundation; either version 2, or (at your option)
// any later version.
//
// The SC Toolkit is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Library General Public License for more details.
//
// You should have received a copy of the GNU Library General Public License
// along with the SC Toolkit; see the file COPYING.LIB.  If not, write to
// the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
//
// The U.S. Government is granted a limited license as per AL 91-7.
//
 
#ifndef _chemistry_qc_basis_orthog_h
#define _chemistry_qc_basis_orthog_h
 
#include <util/state/state.h>
#include <math/scmat/matrix.h>
 
namespace sc {
 
class OverlapOrthog: virtual public SavableState {
  public:
 
    enum OrthogMethod { Symmetric=1, Canonical=2, GramSchmidt=3 };
    static OrthogMethod default_orthog_method() { return Symmetric; }
    static double default_lindep_tol() { return 1e-8; }
 
  private:
    int debug_;
 
    RefSCDimension dim_;
    RefSCDimension orthog_dim_;
 
    // The tolerance for linearly independent basis functions.
    // The intepretation depends on the orthogonalization method.
    double lindep_tol_;
    // The number of linearly dependent functions
    int nlindep_;
    // The orthogonalization method
    OrthogMethod orthog_method_;
    // The orthogonalization matrices
    RefSCMatrix orthog_trans_;
    RefSCMatrix orthog_trans_inverse_;
    // The maximum and minimum residuals from the orthogonalization
    // procedure.  The interpretation depends on the method used.
    // For symmetry and canonical, these are the min and max overlap
    // eigenvalues.  These are the residuals for the basis functions
    // that actually end up being used.
    double min_orthog_res_;
    double max_orthog_res_;
 
    void compute_overlap_eig(RefSCMatrix& overlap_eigvec,
                             RefDiagSCMatrix& overlap_isqrt_eigval,
                             RefDiagSCMatrix& overlap_sqrt_eigval);
    void compute_symmetric_orthog();
    void compute_canonical_orthog();
    void compute_gs_orthog();
    void compute_orthog_trans();
 
    // WARNING: after a SavableState save/restore, these two members will
    // be null.  There is really no need to store these anyway--should be
    // removed.
    RefSymmSCMatrix overlap_;
    Ref<SCMatrixKit> result_kit_; // this kit is used for the result matrices
 
  public:
    OverlapOrthog(OrthogMethod method,
                  const RefSymmSCMatrix &overlap,
                  const Ref<SCMatrixKit> &result_kit,
                  double lindep_tolerance,
                  int debug = 0);
 
    OverlapOrthog(StateIn&);
 
    virtual ~OverlapOrthog();
 
    void save_data_state(StateOut&);
 
    void reinit(OrthogMethod method,
                const RefSymmSCMatrix &overlap,
                const Ref<SCMatrixKit> &result_kit,
                double lindep_tolerance,
                int debug = 0);
 
    double min_orthog_res() const { return min_orthog_res_; }
    double max_orthog_res() const { return max_orthog_res_; }
 
    Ref<OverlapOrthog> copy() const;
 
    OrthogMethod orthog_method() const { return orthog_method_; }
 
    double lindep_tol() const { return lindep_tol_; }
 
    RefSCMatrix basis_to_orthog_basis();
 
    RefSCMatrix basis_to_orthog_basis_inverse();
 
    RefSymmSCMatrix overlap_inverse();
 
    RefSCDimension dim();
    RefSCDimension orthog_dim();
 
    int nlindep();
};
 
}
 
#endif