spline.cc
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29 
30 #include <towr/variables/spline.h>
31 
32 #include <numeric> // std::accumulate
33 
34 namespace towr {
35 
36 Spline::Spline(const VecTimes& poly_durations, int n_dim)
37 {
38  uint n_polys = poly_durations.size();
39 
40  cubic_polys_.assign(n_polys, CubicHermitePolynomial(n_dim));
41  for (int i=0; i<cubic_polys_.size(); ++i) {
42  cubic_polys_.at(i).SetDuration(poly_durations.at(i));
43  }
44 
46 }
47 
48 int
49 Spline::GetSegmentID(double t_global, const VecTimes& durations)
50 {
51  double eps = 1e-10; // double precision
52  assert(t_global >= 0.0);
53 
54  double t = 0;
55  int i=0;
56  for (double d: durations) {
57  t += d;
58 
59  if (t >= t_global-eps) // at junctions, returns previous spline (=)
60  return i;
61 
62  i++;
63  }
64 
65  assert(false); // this should never be reached
66 }
67 
68 std::pair<int,double>
69 Spline::GetLocalTime (double t_global, const VecTimes& durations) const
70 {
71  int id = GetSegmentID(t_global, durations);
72 
73  double t_local = t_global;
74  for (int i=0; i<id; i++)
75  t_local -= durations.at(i);
76 
77  return std::make_pair(id, t_local);
78 }
79 
80 const State
81 Spline::GetPoint(double t_global) const
82 {
83  int id; double t_local;
84  std::tie(id, t_local) = GetLocalTime(t_global, GetPolyDurations());
85 
86  return GetPoint(id, t_local);
87 }
88 
89 const State
90 Spline::GetPoint(int poly_id, double t_local) const
91 {
92  return cubic_polys_.at(poly_id).GetPoint(t_local);
93 }
94 
95 void
97 {
98  for (auto& p : cubic_polys_)
99  p.UpdateCoeff();
100 }
101 
102 int
104 {
105  return cubic_polys_.size();
106 }
107 
110 {
111  VecTimes poly_durations;
112  for (const auto& p : cubic_polys_)
113  poly_durations.push_back(p.GetDuration());
114 
115  return poly_durations;
116 }
117 
118 double
120 {
121  auto v = GetPolyDurations();
122  return std::accumulate(v.begin(), v.end(), 0.0);
123 }
124 
125 } /* namespace towr */
126 
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
Stores at state comprised of values and higher-order derivatives.
Definition: state.h:49
std::vector< double > VecTimes
Definition: spline.h:47
VecPoly cubic_polys_
the sequence of polynomials making up the spline.
Definition: spline.h:89
double GetTotalTime() const
Definition: spline.cc:119
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
static int GetSegmentID(double t_global, const VecTimes &durations)
Definition: spline.cc:49
const State GetPoint(double t) const
Definition: spline.cc:81
int GetPolynomialCount() const
Definition: spline.cc:103
Represents a Cubic-Hermite-Polynomial.
Definition: polynomial.h:109
Spline(const VecTimes &poly_durations, int n_dim)
Definition: spline.cc:36


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