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sillyModifiedGramSchmidt.hpp
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00004 //    Thyra: Interfaces and Support for Abstract Numerical Algorithms
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00041 
00042 #ifndef THYRA_SILLY_MODIFIED_GRAM_SHMIDT_HPP
00043 #define THYRA_SILLY_MODIFIED_GRAM_SHMIDT_HPP
00044 
00045 #include "Thyra_MultiVectorBase.hpp"
00046 #include "Thyra_MultiVectorStdOps.hpp"
00047 #include "Thyra_VectorStdOps.hpp"
00048 #include "Thyra_DetachedMultiVectorView.hpp"
00049 
00050 namespace Thyra {
00051 
00062 template<class Scalar>
00063 void sillyModifiedGramSchmidt(
00064   const Ptr<MultiVectorBase<Scalar> > &V,
00065   const Ptr<RCP<MultiVectorBase<Scalar> > > &R_out
00066   )
00067 {
00068   typedef Teuchos::ScalarTraits<Scalar> ST; using Teuchos::as;
00069   const int n = V->domain()->dim();
00070   *R_out = createMembers(V->domain(), V->domain());
00071   DetachedMultiVectorView<Scalar> R(*(*R_out));
00072   for (int k = 0; k < n; ++k) {
00073     R(k,k) = norm(*V->col(k));
00074     Vt_S(V->col(k).ptr(), ST::one()/R(k,k));
00075     for (int j = k+1; j < n; ++j) {
00076       R(k,j) = scalarProd(*V->col(k), *V->col(j));
00077       Vp_StV(V->col(j).ptr(), -R(k,j), *V->col(k));
00078     }
00079   }
00080 } // end sillyModifiedGramSchmidt
00081 
00082 } // namespace Thyra
00083 
00084 #endif // THYRA_SILLY_MODIFIED_GRAM_SHMIDT_HPP
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