boost/math/interpolators/cardinal_quintic_b_spline.hpp

   1 // Copyright Nick Thompson, 2019
   2 // Use, modification and distribution are subject to the
   3 // Boost Software License, Version 1.0.
   4 // (See accompanying file LICENSE_1_0.txt
   5 // or copy at http://www.boost.org/LICENSE_1_0.txt)
   6
   7 #ifndef BOOST_MATH_INTERPOLATORS_CARDINAL_QUINTIC_B_SPLINE_HPP
   8 #define BOOST_MATH_INTERPOLATORS_CARDINAL_QUINTIC_B_SPLINE_HPP
   9 #include <memory>
  10 #include <limits>
  11 #include <boost/math/interpolators/detail/cardinal_quintic_b_spline_detail.hpp>
  12
  13
  14 namespace boost{ namespace math{ namespace interpolators {
  15
  16 template <class Real>
  17 class cardinal_quintic_b_spline
  18 {
  19 public:
  20     // If you don't know the value of the derivative at the endpoints, leave them as nans and the routine will estimate them.
  21     // y[0] = y(a), y[n - 1] = y(b), step_size = (b - a)/(n -1).
  22     cardinal_quintic_b_spline(const Real* const y,
  23                                 size_t n,
  24                                 Real t0 /* initial time, left endpoint */,
  25                                 Real h  /*spacing, stepsize*/,
  26                                 std::pair<Real, Real> left_endpoint_derivatives = {std::numeric_limits<Real>::quiet_NaN(), std::numeric_limits<Real>::quiet_NaN()},
  27                                 std::pair<Real, Real> right_endpoint_derivatives = {std::numeric_limits<Real>::quiet_NaN(), std::numeric_limits<Real>::quiet_NaN()})
  28      : impl_(std::make_shared<detail::cardinal_quintic_b_spline_detail<Real>>(y, n, t0, h, left_endpoint_derivatives, right_endpoint_derivatives))
  29     {}
  30
  31     // Oh the bizarre error messages if we template this on a RandomAccessContainer:
  32     cardinal_quintic_b_spline(std::vector<Real> const & y,
  33                                 Real t0 /* initial time, left endpoint */,
  34                                 Real h  /*spacing, stepsize*/,
  35                                 std::pair<Real, Real> left_endpoint_derivatives = {std::numeric_limits<Real>::quiet_NaN(), std::numeric_limits<Real>::quiet_NaN()},
  36                                 std::pair<Real, Real> right_endpoint_derivatives = {std::numeric_limits<Real>::quiet_NaN(), std::numeric_limits<Real>::quiet_NaN()})
  37      : impl_(std::make_shared<detail::cardinal_quintic_b_spline_detail<Real>>(y.data(), y.size(), t0, h, left_endpoint_derivatives, right_endpoint_derivatives))
  38     {}
  39
  40
  41     Real operator()(Real t) const {
  42         return impl_->operator()(t);
  43     }
  44
  45     Real prime(Real t) const {
  46        return impl_->prime(t);
  47     }
  48
  49     Real double_prime(Real t) const {
  50         return impl_->double_prime(t);
  51     }
  52
  53     Real t_max() const {
  54         return impl_->t_max();
  55     }
  56
  57 private:
  58     std::shared_ptr<detail::cardinal_quintic_b_spline_detail<Real>> impl_;
  59 };
  60
  61 }}}
  62 #endif