90 lines
		
	
	
		
			2.6 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
			
		
		
	
	
			90 lines
		
	
	
		
			2.6 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
| // This file is part of Eigen, a lightweight C++ template library
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| // for linear algebra.
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| //
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| // Copyright (C) 2010-2011 Gael Guennebaud <gael.guennebaud@inria.fr>
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| //
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| // This Source Code Form is subject to the terms of the Mozilla
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| // Public License v. 2.0. If a copy of the MPL was not distributed
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| // with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
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| 
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| #include "common.h"
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| #include <Eigen/LU>
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| 
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| // computes an LU factorization of a general M-by-N matrix A using partial pivoting with row interchanges
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| EIGEN_LAPACK_FUNC(getrf,(int *m, int *n, RealScalar *pa, int *lda, int *ipiv, int *info))
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| {
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|   *info = 0;
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|         if(*m<0)                  *info = -1;
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|   else  if(*n<0)                  *info = -2;
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|   else  if(*lda<std::max(1,*m))   *info = -4;
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|   if(*info!=0)
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|   {
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|     int e = -*info;
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|     return xerbla_(SCALAR_SUFFIX_UP"GETRF", &e, 6);
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|   }
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| 
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|   if(*m==0 || *n==0)
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|     return 0;
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| 
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|   Scalar* a = reinterpret_cast<Scalar*>(pa);
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|   int nb_transpositions;
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|   int ret = int(Eigen::internal::partial_lu_impl<Scalar,ColMajor,int>
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|                      ::blocked_lu(*m, *n, a, *lda, ipiv, nb_transpositions));
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| 
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|   for(int i=0; i<std::min(*m,*n); ++i)
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|     ipiv[i]++;
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| 
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|   if(ret>=0)
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|     *info = ret+1;
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| 
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|   return 0;
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| }
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| 
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| //GETRS solves a system of linear equations
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| //    A * X = B  or  A' * X = B
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| //  with a general N-by-N matrix A using the LU factorization computed  by GETRF
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| EIGEN_LAPACK_FUNC(getrs,(char *trans, int *n, int *nrhs, RealScalar *pa, int *lda, int *ipiv, RealScalar *pb, int *ldb, int *info))
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| {
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|   *info = 0;
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|         if(OP(*trans)==INVALID)  *info = -1;
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|   else  if(*n<0)                 *info = -2;
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|   else  if(*nrhs<0)              *info = -3;
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|   else  if(*lda<std::max(1,*n))  *info = -5;
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|   else  if(*ldb<std::max(1,*n))  *info = -8;
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|   if(*info!=0)
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|   {
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|     int e = -*info;
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|     return xerbla_(SCALAR_SUFFIX_UP"GETRS", &e, 6);
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|   }
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| 
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|   Scalar* a = reinterpret_cast<Scalar*>(pa);
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|   Scalar* b = reinterpret_cast<Scalar*>(pb);
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|   MatrixType lu(a,*n,*n,*lda);
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|   MatrixType B(b,*n,*nrhs,*ldb);
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| 
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|   for(int i=0; i<*n; ++i)
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|     ipiv[i]--;
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|   if(OP(*trans)==NOTR)
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|   {
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|     B = PivotsType(ipiv,*n) * B;
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|     lu.triangularView<UnitLower>().solveInPlace(B);
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|     lu.triangularView<Upper>().solveInPlace(B);
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|   }
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|   else if(OP(*trans)==TR)
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|   {
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|     lu.triangularView<Upper>().transpose().solveInPlace(B);
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|     lu.triangularView<UnitLower>().transpose().solveInPlace(B);
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|     B = PivotsType(ipiv,*n).transpose() * B;
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|   }
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|   else if(OP(*trans)==ADJ)
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|   {
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|     lu.triangularView<Upper>().adjoint().solveInPlace(B);
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|     lu.triangularView<UnitLower>().adjoint().solveInPlace(B);
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|     B = PivotsType(ipiv,*n).transpose() * B;
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|   }
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|   for(int i=0; i<*n; ++i)
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|     ipiv[i]++;
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| 
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|   return 0;
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| }
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