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LSSTDataManagementBasePackage
Scaling1d.h
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22 #ifndef LSST_AFW_MATH_POLYNOMIALS_Scaling1d_h_INCLUDED
23 #define LSST_AFW_MATH_POLYNOMIALS_Scaling1d_h_INCLUDED
24 
25 
26 namespace lsst { namespace geom { namespace polynomials {
27 
46 class Scaling1d {
47 public:
48 
50  Scaling1d(double scale, double shift) noexcept:
51  _scale(scale),
52  _shift(shift)
53  {}
54 
56  Scaling1d(Scaling1d const &) noexcept = default;
57 
59  Scaling1d(Scaling1d &&) noexcept = default;
60 
62  Scaling1d & operator=(Scaling1d const &) noexcept = default;
63 
65  Scaling1d & operator=(Scaling1d &&) noexcept = default;
66 
72  double applyForward(double x) const noexcept {
73  return (x + getShift())*getScale();
74  }
75 
79  double applyInverse(double y) const noexcept {
80  return y/_scale - _shift;
81  }
82 
84  double getScale() const noexcept { return _scale; }
85 
87  double getShift() const noexcept { return _shift; }
88 
96  Scaling1d inverted() const noexcept {
97  return Scaling1d(1.0/_scale, -_shift*_scale);
98  }
99 
107  Scaling1d then(Scaling1d const & second) const noexcept {
108  return Scaling1d(getScale()*second.getScale(),
109  getShift() + second.getShift()/getScale());
110  }
111 
112 private:
113  double _scale;
114  double _shift;
115 };
116 
120 inline Scaling1d makeUnitRangeScaling1d(double min, double max) noexcept {
121  return Scaling1d(2.0/(max - min), -0.5*(min + max));
122 }
123 
124 }}} // namespace lsst::geom::polynomials
125 
126 #endif // !LSST_AFW_MATH_POLYNOMIALS_Scaling1d_h_INCLUDED
y
int y
Definition: SpanSet.cc:49
lsst::geom::polynomials::Scaling1d::getShift
double getShift() const noexcept
Return the additive shift.
Definition: Scaling1d.h:87
lsst::geom::polynomials::Scaling1d::applyForward
double applyForward(double x) const noexcept
Apply the transform in the forward direction.
Definition: Scaling1d.h:72
lsst::afw::table._match.second
second
Definition: _match.py:78
lsst::geom::polynomials::Scaling1d
A 1-d affine transform that can be used to map one interval to another.
Definition: Scaling1d.h:46
lsst::geom::polynomials::Scaling1d::then
Scaling1d then(Scaling1d const &second) const noexcept
Compose two transforms.
Definition: Scaling1d.h:107
lsst::geom::polynomials::Scaling1d::Scaling1d
Scaling1d(Scaling1d const &) noexcept=default
Default copy constructor.
lsst::geom::polynomials::Scaling1d::Scaling1d
Scaling1d(double scale, double shift) noexcept
Construct from the given multiplicative scale and additive shift.
Definition: Scaling1d.h:50
lsst::geom::polynomials::Scaling1d::applyInverse
double applyInverse(double y) const noexcept
Apply the inverse of the forward transform;.
Definition: Scaling1d.h:79
lsst::geom::polynomials::makeUnitRangeScaling1d
Scaling1d makeUnitRangeScaling1d(double min, double max) noexcept
Return a Scaling1d that maps the interval [min, max] to [-1, 1].
Definition: Scaling1d.h:120
x
double x
Definition: ChebyshevBoundedField.cc:277
max
int max
Definition: BoundedField.cc:104
lsst
A base class for image defects.
Definition: imageAlgorithm.dox:1
lsst::geom::polynomials::Scaling1d::inverted
Scaling1d inverted() const noexcept
Invert the transform.
Definition: Scaling1d.h:96
lsst::geom
Definition: geomOperators.dox:4
min
int min
Definition: BoundedField.cc:103
lsst::afw.display.ds9.scale
def scale(algorithm, min, max=None, frame=None)
Definition: ds9.py:109
lsst::geom::polynomials::Scaling1d::getScale
double getScale() const noexcept
Return the multiplicative scaling.
Definition: Scaling1d.h:84
lsst::geom::polynomials::Scaling1d::Scaling1d
Scaling1d(Scaling1d &&) noexcept=default
Default move constructor.