dust3d/third_party/libigl/include/igl/active_set.h

112 lines
3.8 KiB
C++

// This file is part of libigl, a simple c++ geometry processing library.
//
// Copyright (C) 2013 Alec Jacobson <alecjacobson@gmail.com>
//
// This Source Code Form is subject to the terms of the Mozilla Public License
// v. 2.0. If a copy of the MPL was not distributed with this file, You can
// obtain one at http://mozilla.org/MPL/2.0/.
#ifndef IGL_ACTIVE_SET_H
#define IGL_ACTIVE_SET_H
#include "igl_inline.h"
#include "SolverStatus.h"
#include <Eigen/Core>
#include <Eigen/Sparse>
namespace igl
{
struct active_set_params;
// Known Bugs: rows of [Aeq;Aieq] **must** be linearly independent. Should be
// using QR decomposition otherwise:
// http://www.okstate.edu/sas/v8/sashtml/ormp/chap5/sect32.htm
//
// ACTIVE_SET Minimize quadratic energy
//
// 0.5*Z'*A*Z + Z'*B + C with constraints
//
// that Z(known) = Y, optionally also subject to the constraints Aeq*Z = Beq,
// and further optionally subject to the linear inequality constraints that
// Aieq*Z <= Bieq and constant inequality constraints lx <= x <= ux
//
// Inputs:
// A n by n matrix of quadratic coefficients
// B n by 1 column of linear coefficients
// known list of indices to known rows in Z
// Y list of fixed values corresponding to known rows in Z
// Aeq meq by n list of linear equality constraint coefficients
// Beq meq by 1 list of linear equality constraint constant values
// Aieq mieq by n list of linear inequality constraint coefficients
// Bieq mieq by 1 list of linear inequality constraint constant values
// lx n by 1 list of lower bounds [] implies -Inf
// ux n by 1 list of upper bounds [] implies Inf
// params struct of additional parameters (see below)
// Z if not empty, is taken to be an n by 1 list of initial guess values
// (see output)
// Outputs:
// Z n by 1 list of solution values
// Returns true on success, false on error
//
// Benchmark: For a harmonic solve on a mesh with 325K facets, matlab 2.2
// secs, igl/min_quad_with_fixed.h 7.1 secs
//
template <
typename AT,
typename DerivedB,
typename Derivedknown,
typename DerivedY,
typename AeqT,
typename DerivedBeq,
typename AieqT,
typename DerivedBieq,
typename Derivedlx,
typename Derivedux,
typename DerivedZ
>
IGL_INLINE igl::SolverStatus active_set(
const Eigen::SparseMatrix<AT>& A,
const Eigen::PlainObjectBase<DerivedB> & B,
const Eigen::PlainObjectBase<Derivedknown> & known,
const Eigen::PlainObjectBase<DerivedY> & Y,
const Eigen::SparseMatrix<AeqT>& Aeq,
const Eigen::PlainObjectBase<DerivedBeq> & Beq,
const Eigen::SparseMatrix<AieqT>& Aieq,
const Eigen::PlainObjectBase<DerivedBieq> & Bieq,
const Eigen::PlainObjectBase<Derivedlx> & lx,
const Eigen::PlainObjectBase<Derivedux> & ux,
const igl::active_set_params & params,
Eigen::PlainObjectBase<DerivedZ> & Z
);
};
#include "EPS.h"
struct igl::active_set_params
{
// Input parameters for active_set:
// Auu_pd whether Auu is positive definite {false}
// max_iter Maximum number of iterations (0 = Infinity, {100})
// inactive_threshold Threshold on Lagrange multiplier values to determine
// whether to keep constraints active {EPS}
// constraint_threshold Threshold on whether constraints are violated (0
// is perfect) {EPS}
// solution_diff_threshold Threshold on the squared norm of the difference
// between two consecutive solutions {EPS}
bool Auu_pd;
int max_iter;
double inactive_threshold;
double constraint_threshold;
double solution_diff_threshold;
active_set_params():
Auu_pd(false),
max_iter(100),
inactive_threshold(igl::DOUBLE_EPS),
constraint_threshold(igl::DOUBLE_EPS),
solution_diff_threshold(igl::DOUBLE_EPS)
{};
};
#ifndef IGL_STATIC_LIBRARY
# include "active_set.cpp"
#endif
#endif