node_spline.cc
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29 
31 
33 
34 namespace towr {
35 
37  const VecTimes& polynomial_durations)
38  : Spline(polynomial_durations, node_variables->GetDim()),
39  NodesObserver(node_variables)
40 {
41  UpdateNodes();
42  jac_wrt_nodes_structure_ = Jacobian(node_variables->GetDim(), node_variables->GetRows());
43 }
44 
45 void
47 {
48  for (int i=0; i<cubic_polys_.size(); ++i) {
49  auto nodes = node_values_->GetBoundaryNodes(i);
50  cubic_polys_.at(i).SetNodes(nodes.front(), nodes.back());
51  }
52 
54 }
55 
56 int
58 {
59  return node_values_->GetRows();
60 }
61 
63 NodeSpline::GetJacobianWrtNodes (double t_global, Dx dxdt) const
64 {
65  int id; double t_local;
66  std::tie(id, t_local) = GetLocalTime(t_global, GetPolyDurations());
67 
68  return GetJacobianWrtNodes(id, t_local, dxdt);
69 }
70 
72 NodeSpline::GetJacobianWrtNodes (int id, double t_local, Dx dxdt) const
73 {
75  FillJacobianWrtNodes(id, t_local, dxdt, jac, false);
76 
77  // needed to avoid Eigen::assert failure "wrong storage order" triggered
78  // in dynamic_constraint.cc
79  jac.makeCompressed();
80 
81  return jac;
82 }
83 
84 void
85 NodeSpline::FillJacobianWrtNodes (int poly_id, double t_local, Dx dxdt,
86  Jacobian& jac, bool fill_with_zeros) const
87 {
88  for (int idx=0; idx<jac.cols(); ++idx) {
89  for (auto nvi : node_values_->GetNodeValuesInfo(idx)) {
90  for (auto side : {NodesVariables::Side::Start, NodesVariables::Side::End}) { // every jacobian is affected by two nodes
91  int node = node_values_->GetNodeId(poly_id, side);
92 
93  if (node == nvi.id_) {
94  double val = 0.0;
95 
96  if (side == NodesVariables::Side::Start)
97  val = cubic_polys_.at(poly_id).GetDerivativeWrtStartNode(dxdt, nvi.deriv_, t_local);
98  else if (side == NodesVariables::Side::End)
99  val = cubic_polys_.at(poly_id).GetDerivativeWrtEndNode(dxdt, nvi.deriv_, t_local);
100  else
101  assert(false); // this shouldn't happen
102 
103  // if only want structure
104  if (fill_with_zeros)
105  val = 0.0;
106 
107  jac.coeffRef(nvi.dim_, idx) += val;
108  }
109  }
110  }
111  }
112 }
113 
114 } /* namespace towr */
Base class to receive up-to-date values of the NodeVariables.
std::pair< int, double > GetLocalTime(double t_global, const VecTimes &d) const
How much time of the current segment has passed at t_global.
Definition: spline.cc:69
Jacobian GetJacobianWrtNodes(double t, Dx dxdt) const
How the spline changes when the node values change.
Definition: node_spline.cc:63
Jacobian jac_wrt_nodes_structure_
Definition: node_spline.h:108
A spline built from a sequence of cubic polynomials.
Definition: spline.h:45
NodeSubjectPtr node_values_
std::vector< double > VecTimes
Definition: spline.h:47
void UpdateNodes()
Called by subject to update the polynomials with new node values.
Definition: node_spline.cc:46
VecPoly cubic_polys_
the sequence of polynomials making up the spline.
Definition: spline.h:89
Position and velocity of nodes used to generate a Hermite spline.
static int GetNodeId(int poly_id, Side side)
The node ID that belongs to a specific side of a specific polynomial.
void UpdatePolynomialCoeff()
Updates the cubic-Hermite polynomial coefficients using the currently set nodes values and durations...
Definition: spline.cc:96
VecTimes GetPolyDurations() const
Definition: spline.cc:109
Eigen::SparseMatrix< double, Eigen::RowMajor > Jacobian
Definition: node_spline.h:52
NodeSpline(NodeSubjectPtr const node_variables, const VecTimes &polynomial_durations)
Constructs a spline with constant durations.
Definition: node_spline.cc:36
virtual std::vector< NodeValueInfo > GetNodeValuesInfo(int opt_idx) const =0
Node values affected by one specific optimization variable.
const std::vector< Node > GetBoundaryNodes(int poly_id) const
void FillJacobianWrtNodes(int poly_id, double t_local, Dx dxdt, Jacobian &jac, bool fill_with_zeros) const
Fills specific elements of the Jacobian with respect to nodes.
Definition: node_spline.cc:85
int GetNodeVariablesCount() const
Definition: node_spline.cc:57
int GetRows() const
Dx
< the values or derivative. For motions e.g. position, velocity, ...
Definition: state.h:41


towr
Author(s): Alexander W. Winkler
autogenerated on Fri Apr 2 2021 02:14:16