internal/ceres/suitesparse.h - ceres-solver - Git at Google

 // Ceres Solver - A fast non-linear least squares minimizer
 // Copyright 2023 Google Inc. All rights reserved.
 // http://ceres-solver.org/
 //
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are met:
 //
 // * Redistributions of source code must retain the above copyright notice,
 //   this list of conditions and the following disclaimer.
 // * Redistributions in binary form must reproduce the above copyright notice,
 //   this list of conditions and the following disclaimer in the documentation
 //   and/or other materials provided with the distribution.
 // * Neither the name of Google Inc. nor the names of its contributors may be
 //   used to endorse or promote products derived from this software without
 //   specific prior written permission.
 //
 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 // AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 // IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 // ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 // LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 // CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 // SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 // INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 // CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 // ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 // POSSIBILITY OF SUCH DAMAGE.
 //
 // Author: sameeragarwal@google.com (Sameer Agarwal)
 //
 // A simple C++ interface to the SuiteSparse and CHOLMOD libraries.

 #ifndef CERES_INTERNAL_SUITESPARSE_H_
 #define CERES_INTERNAL_SUITESPARSE_H_

 // This include must come before any #ifndef check on Ceres compile options.
 #include "ceres/internal/config.h"

 #ifndef CERES_NO_SUITESPARSE

 #include <cstring>
 #include <memory>
 #include <string>
 #include <vector>

 #include "SuiteSparseQR.hpp"
 #include "ceres/block_structure.h"
 #include "ceres/internal/disable_warnings.h"
 #include "ceres/linear_solver.h"
 #include "ceres/sparse_cholesky.h"
 #include "cholmod.h"

 namespace ceres::internal {

 class CompressedRowSparseMatrix;
 class TripletSparseMatrix;

 // The raw CHOLMOD and SuiteSparseQR libraries have a slightly
 // cumbersome c like calling format. This object abstracts it away and
 // provides the user with a simpler interface. The methods here cannot
 // be static as a cholmod_common object serves as a global variable
 // for all cholmod function calls.
 class CERES_NO_EXPORT SuiteSparse {
  public:
   SuiteSparse();
   ~SuiteSparse();

   // Functions for building cholmod_sparse objects from sparse
   // matrices stored in triplet form. The matrix A is not
   // modified. Called owns the result.
   cholmod_sparse* CreateSparseMatrix(TripletSparseMatrix* A);

   // This function works like CreateSparseMatrix, except that the
   // return value corresponds to A' rather than A.
   cholmod_sparse* CreateSparseMatrixTranspose(TripletSparseMatrix* A);

   // Create a cholmod_sparse wrapper around the contents of A. This is
   // a shallow object, which refers to the contents of A and does not
   // use the SuiteSparse machinery to allocate memory.
   cholmod_sparse CreateSparseMatrixTransposeView(CompressedRowSparseMatrix* A);

   // Create a cholmod_dense vector around the contents of the array x.
   // This is a shallow object, which refers to the contents of x and
   // does not use the SuiteSparse machinery to allocate memory.
   cholmod_dense CreateDenseVectorView(const double* x, int size);

   // Given a vector x, build a cholmod_dense vector of size out_size
   // with the first in_size entries copied from x. If x is nullptr, then
   // an all zeros vector is returned. Caller owns the result.
   cholmod_dense* CreateDenseVector(const double* x, int in_size, int out_size);

   // The matrix A is scaled using the matrix whose diagonal is the
   // vector scale. mode describes how scaling is applied. Possible
   // values are CHOLMOD_ROW for row scaling - diag(scale) * A,
   // CHOLMOD_COL for column scaling - A * diag(scale) and CHOLMOD_SYM
   // for symmetric scaling which scales both the rows and the columns
   // - diag(scale) * A * diag(scale).
   void Scale(cholmod_dense* scale, int mode, cholmod_sparse* A) {
     cholmod_scale(scale, mode, A, &cc_);
   }

   // Create and return a matrix m = A * A'. Caller owns the
   // result. The matrix A is not modified.
   cholmod_sparse* AATranspose(cholmod_sparse* A) {
     cholmod_sparse* m = cholmod_aat(A, nullptr, A->nrow, 1, &cc_);
     m->stype = 1;  // Pay attention to the upper triangular part.
     return m;
   }

   // y = alpha * A * x + beta * y. Only y is modified.
   void SparseDenseMultiply(cholmod_sparse* A,
                            double alpha,
                            double beta,
                            cholmod_dense* x,
                            cholmod_dense* y) {
     double alpha_[2] = {alpha, 0};
     double beta_[2] = {beta, 0};
     cholmod_sdmult(A, 0, alpha_, beta_, x, y, &cc_);
   }

   // Compute a symbolic factorization for A or AA' (if A is
   // unsymmetric). If ordering_type is NATURAL, then no fill reducing
   // ordering is computed, otherwise depending on the value of
   // ordering_type AMD or Nested Dissection is used to compute a fill
   // reducing ordering before the symbolic factorization is computed.
   //
   // A is not modified, only the pattern of non-zeros of A is used,
   // the actual numerical values in A are of no consequence.
   //
   // message contains an explanation of the failures if any.
   //
   // Caller owns the result.
   cholmod_factor* AnalyzeCholesky(cholmod_sparse* A,
                                   OrderingType ordering_type,
                                   std::string* message);

   // Block oriented version of AnalyzeCholesky.
   cholmod_factor* BlockAnalyzeCholesky(cholmod_sparse* A,
                                        OrderingType ordering_type,
                                        const std::vector<Block>& row_blocks,
                                        const std::vector<Block>& col_blocks,
                                        std::string* message);

   // If A is symmetric, then compute the symbolic Cholesky
   // factorization of A(ordering, ordering). If A is unsymmetric, then
   // compute the symbolic factorization of
   // A(ordering,:) A(ordering,:)'.
   //
   // A is not modified, only the pattern of non-zeros of A is used,
   // the actual numerical values in A are of no consequence.
   //
   // message contains an explanation of the failures if any.
   //
   // Caller owns the result.
   cholmod_factor* AnalyzeCholeskyWithGivenOrdering(
       cholmod_sparse* A,
       const std::vector<int>& ordering,
       std::string* message);

   // Use the symbolic factorization in L, to find the numerical
   // factorization for the matrix A or AA^T. Return true if
   // successful, false otherwise. L contains the numeric factorization
   // on return.
   //
   // message contains an explanation of the failures if any.
   LinearSolverTerminationType Cholesky(cholmod_sparse* A,
                                        cholmod_factor* L,
                                        std::string* message);

   // Given a Cholesky factorization of a matrix A = LL^T, solve the
   // linear system Ax = b, and return the result. If the Solve fails
   // nullptr is returned. Caller owns the result.
   //
   // message contains an explanation of the failures if any.
   cholmod_dense* Solve(cholmod_factor* L,
                        cholmod_dense* b,
                        std::string* message);

   // Find a fill reducing ordering. ordering is expected to be large
   // enough to hold the ordering. ordering_type must be AMD or NESDIS.
   bool Ordering(cholmod_sparse* matrix,
                 OrderingType ordering_type,
                 int* ordering);

   // Find the block oriented fill reducing ordering of a matrix A,
   // whose row and column blocks are given by row_blocks, and
   // col_blocks respectively. The matrix may or may not be
   // symmetric. The entries of col_blocks do not need to sum to the
   // number of columns in A. If this is the case, only the first
   // sum(col_blocks) are used to compute the ordering.
   //
   // By virtue of the modeling layer in Ceres being block oriented,
   // all the matrices used by Ceres are also block oriented. When
   // doing sparse direct factorization of these matrices the
   // fill-reducing ordering algorithms can either be run on the block
   // or the scalar form of these matrices. But since the underlying
   // matrices are block oriented, it is worth running the fill
   // reducing ordering on just the block structure of these matrices
   // and then lifting these block orderings to a full scalar
   // ordering. This preserves the block structure of the permuted
   // matrix, and exposes more of the super-nodal structure of the
   // matrix to the numerical factorization routines.
   bool BlockOrdering(const cholmod_sparse* A,
                      OrderingType ordering_type,
                      const std::vector<Block>& row_blocks,
                      const std::vector<Block>& col_blocks,
                      std::vector<int>* ordering);

   // Nested dissection is only available if SuiteSparse is compiled
   // with Metis support.
   static bool IsNestedDissectionAvailable();

   // Find a fill reducing approximate minimum degree
   // ordering. constraints is an array which associates with each
   // column of the matrix an elimination group. i.e., all columns in
   // group 0 are eliminated first, all columns in group 1 are
   // eliminated next etc. This function finds a fill reducing ordering
   // that obeys these constraints.
   //
   // Calling ApproximateMinimumDegreeOrdering is equivalent to calling
   // ConstrainedApproximateMinimumDegreeOrdering with a constraint
   // array that puts all columns in the same elimination group.
   bool ConstrainedApproximateMinimumDegreeOrdering(cholmod_sparse* matrix,
                                                    int* constraints,
                                                    int* ordering);

   void Free(cholmod_sparse* m) { cholmod_free_sparse(&m, &cc_); }
   void Free(cholmod_dense* m) { cholmod_free_dense(&m, &cc_); }
   void Free(cholmod_factor* m) { cholmod_free_factor(&m, &cc_); }

   void Print(cholmod_sparse* m, const std::string& name) {
     cholmod_print_sparse(m, const_cast<char*>(name.c_str()), &cc_);
   }

   void Print(cholmod_dense* m, const std::string& name) {
     cholmod_print_dense(m, const_cast<char*>(name.c_str()), &cc_);
   }

   void Print(cholmod_triplet* m, const std::string& name) {
     cholmod_print_triplet(m, const_cast<char*>(name.c_str()), &cc_);
   }

   cholmod_common* mutable_cc() { return &cc_; }

  private:
   cholmod_common cc_;
 };

 class CERES_NO_EXPORT SuiteSparseCholesky final : public SparseCholesky {
  public:
   static std::unique_ptr<SparseCholesky> Create(OrderingType ordering_type);

   // SparseCholesky interface.
   ~SuiteSparseCholesky() override;
   CompressedRowSparseMatrix::StorageType StorageType() const final;
   LinearSolverTerminationType Factorize(CompressedRowSparseMatrix* lhs,
                                         std::string* message) final;
   LinearSolverTerminationType Solve(const double* rhs,
                                     double* solution,
                                     std::string* message) final;

  private:
   explicit SuiteSparseCholesky(const OrderingType ordering_type);

   const OrderingType ordering_type_;
   SuiteSparse ss_;
   cholmod_factor* factor_ = nullptr;
 };

 class CERES_NO_EXPORT FloatSuiteSparseCholesky final : public SparseCholesky {
  public:
   static std::unique_ptr<SparseCholesky> Create(OrderingType ordering_type);

   // SparseCholesky interface.
   ~FloatSuiteSparseCholesky() override;
   CompressedRowSparseMatrix::StorageType StorageType() const final;
   LinearSolverTerminationType Factorize(CompressedRowSparseMatrix* lhs,
                                         std::string* message) final;
   LinearSolverTerminationType Solve(const double* rhs,
                                     double* solution,
                                     std::string* message) final;

  private:
   explicit FloatSuiteSparseCholesky(const OrderingType ordering_type);

   const OrderingType ordering_type_;
   SuiteSparse ss_;
   cholmod_factor* factor_ = nullptr;
   Eigen::VectorXf float_lhs_values_;
   Eigen::VectorXf float_rhs_;
 };

 }  // namespace ceres::internal

 #include "ceres/internal/reenable_warnings.h"

 #else  // CERES_NO_SUITESPARSE

 using cholmod_factor = void;

 #include "ceres/internal/disable_warnings.h"

 namespace ceres {
 namespace internal {

 class CERES_NO_EXPORT SuiteSparse {
  public:
   // Nested dissection is only available if SuiteSparse is compiled
   // with Metis support.
   static bool IsNestedDissectionAvailable() { return false; }
   void Free(void* /*arg*/) {}
 };

 }  // namespace internal
 }  // namespace ceres

 #include "ceres/internal/reenable_warnings.h"

 #endif  // CERES_NO_SUITESPARSE

 #endif  // CERES_INTERNAL_SUITESPARSE_H_
	// Ceres Solver - A fast non-linear least squares minimizer
	// Copyright 2023 Google Inc. All rights reserved.
	// http://ceres-solver.org/
	//
	// Redistribution and use in source and binary forms, with or without
	// modification, are permitted provided that the following conditions are met:
	//
	// * Redistributions of source code must retain the above copyright notice,
	// this list of conditions and the following disclaimer.
	// * Redistributions in binary form must reproduce the above copyright notice,
	// this list of conditions and the following disclaimer in the documentation
	// and/or other materials provided with the distribution.
	// * Neither the name of Google Inc. nor the names of its contributors may be
	// used to endorse or promote products derived from this software without
	// specific prior written permission.
	//
	// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
	// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
	// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
	// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
	// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
	// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
	// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
	// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
	// POSSIBILITY OF SUCH DAMAGE.
	//
	// Author: sameeragarwal@google.com (Sameer Agarwal)
	//
	// A simple C++ interface to the SuiteSparse and CHOLMOD libraries.

	#ifndef CERES_INTERNAL_SUITESPARSE_H_
	#define CERES_INTERNAL_SUITESPARSE_H_

	// This include must come before any #ifndef check on Ceres compile options.
	#include "ceres/internal/config.h"

	#ifndef CERES_NO_SUITESPARSE

	#include <cstring>
	#include <memory>
	#include <string>
	#include <vector>

	#include "SuiteSparseQR.hpp"
	#include "ceres/block_structure.h"
	#include "ceres/internal/disable_warnings.h"
	#include "ceres/linear_solver.h"
	#include "ceres/sparse_cholesky.h"
	#include "cholmod.h"

	namespace ceres::internal {

	class CompressedRowSparseMatrix;
	class TripletSparseMatrix;

	// The raw CHOLMOD and SuiteSparseQR libraries have a slightly
	// cumbersome c like calling format. This object abstracts it away and
	// provides the user with a simpler interface. The methods here cannot
	// be static as a cholmod_common object serves as a global variable
	// for all cholmod function calls.
	class CERES_NO_EXPORT SuiteSparse {
	public:
	SuiteSparse();
	~SuiteSparse();

	// Functions for building cholmod_sparse objects from sparse
	// matrices stored in triplet form. The matrix A is not
	// modified. Called owns the result.
	cholmod_sparse* CreateSparseMatrix(TripletSparseMatrix* A);

	// This function works like CreateSparseMatrix, except that the
	// return value corresponds to A' rather than A.
	cholmod_sparse* CreateSparseMatrixTranspose(TripletSparseMatrix* A);

	// Create a cholmod_sparse wrapper around the contents of A. This is
	// a shallow object, which refers to the contents of A and does not
	// use the SuiteSparse machinery to allocate memory.
	cholmod_sparse CreateSparseMatrixTransposeView(CompressedRowSparseMatrix* A);

	// Create a cholmod_dense vector around the contents of the array x.
	// This is a shallow object, which refers to the contents of x and
	// does not use the SuiteSparse machinery to allocate memory.
	cholmod_dense CreateDenseVectorView(const double* x, int size);

	// Given a vector x, build a cholmod_dense vector of size out_size
	// with the first in_size entries copied from x. If x is nullptr, then
	// an all zeros vector is returned. Caller owns the result.
	cholmod_dense* CreateDenseVector(const double* x, int in_size, int out_size);

	// The matrix A is scaled using the matrix whose diagonal is the
	// vector scale. mode describes how scaling is applied. Possible
	// values are CHOLMOD_ROW for row scaling - diag(scale) * A,
	// CHOLMOD_COL for column scaling - A * diag(scale) and CHOLMOD_SYM
	// for symmetric scaling which scales both the rows and the columns
	// - diag(scale) * A * diag(scale).
	void Scale(cholmod_dense* scale, int mode, cholmod_sparse* A) {
	cholmod_scale(scale, mode, A, &cc_);
	}

	// Create and return a matrix m = A * A'. Caller owns the
	// result. The matrix A is not modified.
	cholmod_sparse* AATranspose(cholmod_sparse* A) {
	cholmod_sparse* m = cholmod_aat(A, nullptr, A->nrow, 1, &cc_);
	m->stype = 1; // Pay attention to the upper triangular part.
	return m;
	}

	// y = alpha * A * x + beta * y. Only y is modified.
	void SparseDenseMultiply(cholmod_sparse* A,
	double alpha,
	double beta,
	cholmod_dense* x,
	cholmod_dense* y) {
	double alpha_[2] = {alpha, 0};
	double beta_[2] = {beta, 0};
	cholmod_sdmult(A, 0, alpha_, beta_, x, y, &cc_);
	}

	// Compute a symbolic factorization for A or AA' (if A is
	// unsymmetric). If ordering_type is NATURAL, then no fill reducing
	// ordering is computed, otherwise depending on the value of
	// ordering_type AMD or Nested Dissection is used to compute a fill
	// reducing ordering before the symbolic factorization is computed.
	//
	// A is not modified, only the pattern of non-zeros of A is used,
	// the actual numerical values in A are of no consequence.
	//
	// message contains an explanation of the failures if any.
	//
	// Caller owns the result.
	cholmod_factor* AnalyzeCholesky(cholmod_sparse* A,
	OrderingType ordering_type,
	std::string* message);

	// Block oriented version of AnalyzeCholesky.
	cholmod_factor* BlockAnalyzeCholesky(cholmod_sparse* A,
	OrderingType ordering_type,
	const std::vector<Block>& row_blocks,
	const std::vector<Block>& col_blocks,
	std::string* message);

	// If A is symmetric, then compute the symbolic Cholesky
	// factorization of A(ordering, ordering). If A is unsymmetric, then
	// compute the symbolic factorization of
	// A(ordering,:) A(ordering,:)'.
	//
	// A is not modified, only the pattern of non-zeros of A is used,
	// the actual numerical values in A are of no consequence.
	//
	// message contains an explanation of the failures if any.
	//
	// Caller owns the result.
	cholmod_factor* AnalyzeCholeskyWithGivenOrdering(
	cholmod_sparse* A,
	const std::vector<int>& ordering,
	std::string* message);

	// Use the symbolic factorization in L, to find the numerical
	// factorization for the matrix A or AA^T. Return true if
	// successful, false otherwise. L contains the numeric factorization
	// on return.
	//
	// message contains an explanation of the failures if any.
	LinearSolverTerminationType Cholesky(cholmod_sparse* A,
	cholmod_factor* L,
	std::string* message);

	// Given a Cholesky factorization of a matrix A = LL^T, solve the
	// linear system Ax = b, and return the result. If the Solve fails
	// nullptr is returned. Caller owns the result.
	//
	// message contains an explanation of the failures if any.
	cholmod_dense* Solve(cholmod_factor* L,
	cholmod_dense* b,
	std::string* message);

	// Find a fill reducing ordering. ordering is expected to be large
	// enough to hold the ordering. ordering_type must be AMD or NESDIS.
	bool Ordering(cholmod_sparse* matrix,
	OrderingType ordering_type,
	int* ordering);

	// Find the block oriented fill reducing ordering of a matrix A,
	// whose row and column blocks are given by row_blocks, and
	// col_blocks respectively. The matrix may or may not be
	// symmetric. The entries of col_blocks do not need to sum to the
	// number of columns in A. If this is the case, only the first
	// sum(col_blocks) are used to compute the ordering.
	//
	// By virtue of the modeling layer in Ceres being block oriented,
	// all the matrices used by Ceres are also block oriented. When
	// doing sparse direct factorization of these matrices the
	// fill-reducing ordering algorithms can either be run on the block
	// or the scalar form of these matrices. But since the underlying
	// matrices are block oriented, it is worth running the fill
	// reducing ordering on just the block structure of these matrices
	// and then lifting these block orderings to a full scalar
	// ordering. This preserves the block structure of the permuted
	// matrix, and exposes more of the super-nodal structure of the
	// matrix to the numerical factorization routines.
	bool BlockOrdering(const cholmod_sparse* A,
	OrderingType ordering_type,
	const std::vector<Block>& row_blocks,
	const std::vector<Block>& col_blocks,
	std::vector<int>* ordering);

	// Nested dissection is only available if SuiteSparse is compiled
	// with Metis support.
	static bool IsNestedDissectionAvailable();

	// Find a fill reducing approximate minimum degree
	// ordering. constraints is an array which associates with each
	// column of the matrix an elimination group. i.e., all columns in
	// group 0 are eliminated first, all columns in group 1 are
	// eliminated next etc. This function finds a fill reducing ordering
	// that obeys these constraints.
	//
	// Calling ApproximateMinimumDegreeOrdering is equivalent to calling
	// ConstrainedApproximateMinimumDegreeOrdering with a constraint
	// array that puts all columns in the same elimination group.
	bool ConstrainedApproximateMinimumDegreeOrdering(cholmod_sparse* matrix,
	int* constraints,
	int* ordering);

	void Free(cholmod_sparse* m) { cholmod_free_sparse(&m, &cc_); }
	void Free(cholmod_dense* m) { cholmod_free_dense(&m, &cc_); }
	void Free(cholmod_factor* m) { cholmod_free_factor(&m, &cc_); }

	void Print(cholmod_sparse* m, const std::string& name) {
	cholmod_print_sparse(m, const_cast<char*>(name.c_str()), &cc_);
	}

	void Print(cholmod_dense* m, const std::string& name) {
	cholmod_print_dense(m, const_cast<char*>(name.c_str()), &cc_);
	}

	void Print(cholmod_triplet* m, const std::string& name) {
	cholmod_print_triplet(m, const_cast<char*>(name.c_str()), &cc_);
	}

	cholmod_common* mutable_cc() { return &cc_; }

	private:
	cholmod_common cc_;
	};

	class CERES_NO_EXPORT SuiteSparseCholesky final : public SparseCholesky {
	public:
	static std::unique_ptr<SparseCholesky> Create(OrderingType ordering_type);

	// SparseCholesky interface.
	~SuiteSparseCholesky() override;
	CompressedRowSparseMatrix::StorageType StorageType() const final;
	LinearSolverTerminationType Factorize(CompressedRowSparseMatrix* lhs,
	std::string* message) final;
	LinearSolverTerminationType Solve(const double* rhs,
	double* solution,
	std::string* message) final;

	private:
	explicit SuiteSparseCholesky(const OrderingType ordering_type);

	const OrderingType ordering_type_;
	SuiteSparse ss_;
	cholmod_factor* factor_ = nullptr;
	};

	class CERES_NO_EXPORT FloatSuiteSparseCholesky final : public SparseCholesky {
	public:
	static std::unique_ptr<SparseCholesky> Create(OrderingType ordering_type);

	// SparseCholesky interface.
	~FloatSuiteSparseCholesky() override;
	CompressedRowSparseMatrix::StorageType StorageType() const final;
	LinearSolverTerminationType Factorize(CompressedRowSparseMatrix* lhs,
	std::string* message) final;
	LinearSolverTerminationType Solve(const double* rhs,
	double* solution,
	std::string* message) final;

	private:
	explicit FloatSuiteSparseCholesky(const OrderingType ordering_type);

	const OrderingType ordering_type_;
	SuiteSparse ss_;
	cholmod_factor* factor_ = nullptr;
	Eigen::VectorXf float_lhs_values_;
	Eigen::VectorXf float_rhs_;
	};

	} // namespace ceres::internal

	#include "ceres/internal/reenable_warnings.h"

	#else // CERES_NO_SUITESPARSE

	using cholmod_factor = void;

	#include "ceres/internal/disable_warnings.h"

	namespace ceres {
	namespace internal {

	class CERES_NO_EXPORT SuiteSparse {
	public:
	// Nested dissection is only available if SuiteSparse is compiled
	// with Metis support.
	static bool IsNestedDissectionAvailable() { return false; }
	void Free(void* /arg/) {}
	};

	} // namespace internal
	} // namespace ceres

	#include "ceres/internal/reenable_warnings.h"

	#endif // CERES_NO_SUITESPARSE

	#endif // CERES_INTERNAL_SUITESPARSE_H_