lsst::geom::polynomials::Function1d< Basis_ > Class Template Reference

A 1-d function defined by a series expansion and its coefficients. More...

#include <Function1d.h>

Public Types
using	iterator = double *
using	const_iterator = double const *
using	Basis = Basis_
	The basis type used by this function.

Public Member Functions
	Function1d (Basis const &basis)
	Construct with zero-valued coefficients.
	Function1d (Basis const &basis, Eigen::VectorXd const &coefficients)
	Construct with coefficients from an Eigen object.
template<typename Iterator>
	Function1d (Basis const &basis, Iterator first, Iterator last)
	Construct by copying coefficients from an STL iterator range.
	Function1d (Function1d const &)=default
	Default copy constructor.
	Function1d (Function1d &&)=default
	Default move constructor.
Function1d &	operator= (Function1d const &)=default
	Default copy assignment.
Function1d &	operator= (Function1d &&)=default
	Default move assignment.
iterator	begin ()
	Iterators over coefficients.
iterator	end ()
const_iterator	cbegin () const
const_iterator	cend () const
const_iterator	begin () const
const_iterator	end () const
Basis const &	getBasis () const
	Return the associated Basis1d object.
std::size_t	size () const
	Return the number of coefficients.
double	operator() (double x, SumMode mode=SumMode::FAST) const
	Evaluate the function at the given point.
double &	operator[] (std::size_t n)
	Return the coefficient associated with the nth basis function.
double const &	operator[] (std::size_t n) const
auto	getCoefficients ()
	Return the coefficient vector as an Eigen matrix-like object.
auto	getCoefficients () const
Function1d< typename Basis::Scaled >	scaled (Scaling1d const &scaling) const
	Return a new function that applies the given scaling to all points before evaluation.

Detailed Description

template<typename Basis_>
class lsst::geom::polynomials::Function1d< Basis_ >

A 1-d function defined by a series expansion and its coefficients.

A Function1d combines a Basis1d that defines basis functions \(B_n(x)\) with a vector of associated coefficients \(a_n\). Evaluating the function computes

\[ \sum_{n=0}^{n \le N} a_n B_n(x) \]

Definition at line 42 of file Function1d.h.

Member Typedef Documentation

Basis

template<typename Basis_>

using lsst::geom::polynomials::Function1d< Basis_ >::Basis = Basis_

The basis type used by this function.

Definition at line 49 of file Function1d.h.

const_iterator

template<typename Basis_>

using lsst::geom::polynomials::Function1d< Basis_ >::const_iterator = double const *

Definition at line 46 of file Function1d.h.

iterator

template<typename Basis_>

using lsst::geom::polynomials::Function1d< Basis_ >::iterator = double *

Definition at line 45 of file Function1d.h.

Constructor & Destructor Documentation

Function1d() [1/5]

template<typename Basis_>

lsst::geom::polynomials::Function1d< Basis_ >::Function1d ( Basis const & basis )

inlineexplicit

Construct with zero-valued coefficients.

Definition at line 52 of file Function1d.h.

                                             :
        _basis(basis),
        _coefficients(Eigen::VectorXd::Zero(basis.size()))
    {}

Function1d() [2/5]

template<typename Basis_>

lsst::geom::polynomials::Function1d< Basis_ >::Function1d ( Basis const & basis, Eigen::VectorXd const & coefficients )

inline

Construct with coefficients from an Eigen object.

Definition at line 58 of file Function1d.h.

                                                                        :
        _basis(basis),
        _coefficients(coefficients)
    {
        assert(basis.size() == static_cast<std::size_t>(_coefficients.size()));
    }

Function1d() [3/5]

template<typename Basis_>

template<typename Iterator>

lsst::geom::polynomials::Function1d< Basis_ >::Function1d ( Basis const & basis, Iterator first, Iterator last )

inline

Construct by copying coefficients from an STL iterator range.

Definition at line 67 of file Function1d.h.

                                                                   :
        _basis(basis),
        _coefficients(basis.size())
    {
        assert(std::distance(first, last) == static_cast<std::ptrdiff_t>(basis.size()));
        std::copy(first, last, &_coefficients[0]);
    }

Function1d() [4/5]

template<typename Basis_>

lsst::geom::polynomials::Function1d< Basis_ >::Function1d ( Function1d< Basis_ > const & )

default

Default copy constructor.

Function1d() [5/5]

template<typename Basis_>

lsst::geom::polynomials::Function1d< Basis_ >::Function1d ( Function1d< Basis_ > && )

default

Default move constructor.

Member Function Documentation

begin() [1/2]

template<typename Basis_>

iterator lsst::geom::polynomials::Function1d< Basis_ >::begin ( )

inline

Iterators over coefficients.

Definition at line 89 of file Function1d.h.

{ return _coefficients.data(); }

begin() [2/2]

template<typename Basis_>

const_iterator lsst::geom::polynomials::Function1d< Basis_ >::begin ( ) const

inline

Definition at line 93 of file Function1d.h.

{ return _coefficients.data(); }

cbegin()

template<typename Basis_>

const_iterator lsst::geom::polynomials::Function1d< Basis_ >::cbegin ( ) const

inline

Definition at line 91 of file Function1d.h.

{ return _coefficients.data(); }

cend()

template<typename Basis_>

const_iterator lsst::geom::polynomials::Function1d< Basis_ >::cend ( ) const

inline

Definition at line 92 of file Function1d.h.

{ return begin() + size(); }

end() [1/2]

template<typename Basis_>

iterator lsst::geom::polynomials::Function1d< Basis_ >::end ( )

inline

Definition at line 90 of file Function1d.h.

{ return begin() + size(); }

end() [2/2]

template<typename Basis_>

const_iterator lsst::geom::polynomials::Function1d< Basis_ >::end ( ) const

inline

Definition at line 94 of file Function1d.h.

{ return begin() + size(); }

getBasis()

template<typename Basis_>

Basis const & lsst::geom::polynomials::Function1d< Basis_ >::getBasis ( ) const

inline

Return the associated Basis1d object.

Definition at line 98 of file Function1d.h.

{ return _basis; }

getCoefficients() [1/2]

template<typename Basis_>

auto lsst::geom::polynomials::Function1d< Basis_ >::getCoefficients ( )

inline

Return the coefficient vector as an Eigen matrix-like object.

The exact type of the returned object is unspecified, but it is guaranteed to be a view.

Definition at line 125 of file Function1d.h.

                           {
        // Return a block view to ensure the caller only modify the values, not the size.
        return _coefficients.head(size());
    }

getCoefficients() [2/2]

template<typename Basis_>

auto lsst::geom::polynomials::Function1d< Basis_ >::getCoefficients ( ) const

inline

Definition at line 129 of file Function1d.h.

{ return _coefficients.head(size()); }

operator()()

template<typename Basis_>

double lsst::geom::polynomials::Function1d< Basis_ >::operator() ( double x, SumMode mode = SumMode::FAST ) const

inline

Evaluate the function at the given point.

Definition at line 104 of file Function1d.h.

                                                                {
        return _basis.sumWith(x, _coefficients, mode);
    }

operator=() [1/2]

template<typename Basis_>

Function1d & lsst::geom::polynomials::Function1d< Basis_ >::operator= ( Function1d< Basis_ > && )

default

Default move assignment.

operator=() [2/2]

template<typename Basis_>

Function1d & lsst::geom::polynomials::Function1d< Basis_ >::operator= ( Function1d< Basis_ > const & )

default

Default copy assignment.

operator[]() [1/2]

template<typename Basis_>

double & lsst::geom::polynomials::Function1d< Basis_ >::operator[] ( std::size_t n )

inline

Return the coefficient associated with the nth basis function.

Caller is responsible for ensuring that the given index is valid.

Definition at line 114 of file Function1d.h.

{ return  begin()[n]; }

operator[]() [2/2]

template<typename Basis_>

double const & lsst::geom::polynomials::Function1d< Basis_ >::operator[] ( std::size_t n ) const

inline

Definition at line 115 of file Function1d.h.

{ return begin()[n]; }

scaled()

template<typename Basis_>

Function1d< typename Basis::Scaled > lsst::geom::polynomials::Function1d< Basis_ >::scaled ( Scaling1d const & scaling ) const

inline

Return a new function that applies the given scaling to all points before evaluation.

Definition at line 133 of file Function1d.h.

                                                                             {
        return Function1d<typename Basis::Scaled>(getBasis().scaled(scaling), _coefficients);
    }

size()

template<typename Basis_>

std::size_t lsst::geom::polynomials::Function1d< Basis_ >::size ( ) const

inline

Return the number of coefficients.

Definition at line 101 of file Function1d.h.

{ return _basis.size(); }

---

The documentation for this class was generated from the following file:

• /j/snowflake/release/lsstsw/stack/lsst-scipipe-11.0.0/Linux/geom/g90f42f885a+34c0557caf/include/lsst/geom/polynomials/Function1d.h