LSST Applications g04c3c9f7ca+2075667efa,g1e125bf412+5f448d5fcf,g2079a07aa2+3e9fd84d81,g2305ad1205+b635cf1488,g2bbee38e9b+6c6beb4891,g337abbeb29+6c6beb4891,g33d1c0ed96+6c6beb4891,g3a166c0a6a+6c6beb4891,g50ff169b8f+96c6868917,g52b1c1532d+585e252eca,g591dd9f2cf+42f171e1e6,g5c3423f6d4+d536b04327,g607f77f49a+d536b04327,g6f43f06aed+ca1339dc19,g858d7b2824+d536b04327,g8ee334c5b4+d7f9608c2f,g9963eaa53e+b3dc1655d3,g998f4353bf+d536b04327,g99cad8db69+8ef2408349,g9ddcbc5298+9a081db1e4,ga1e77700b3+2cbb763275,gadfd92a7e4+aec2f3b930,gae0086650b+585e252eca,gb0e22166c9+0e73c8378f,gb3b7280ab2+cb5fdb229e,gbb8dafda3b+a327199e22,gc120e1dc64+88074880ea,gc28159a63d+6c6beb4891,gcdd4ae20e8+bd241b2308,gcde1bda545+903e937d91,gcf0d15dbbd+bd241b2308,gdaeeff99f8+f9a426f77a,gddc38dedce+585e252eca,ge79ae78c31+6c6beb4891,gfbcc870c63+b310236976,w.2024.23
LSST Data Management Base Package
Loading...
Searching...
No Matches
Public Member Functions | List of all members
lsst::jointcal::TanRaDecToPixel Class Reference

This one is the Tangent Plane (called gnomonic) projection (from celestial sphere to tangent plane) More...

#include <AstrometryTransform.h>

Inheritance diagram for lsst::jointcal::TanRaDecToPixel:
lsst::jointcal::AstrometryTransform

Public Member Functions

 TanRaDecToPixel (AstrometryTransformLinear tan2Pix, Point const &tangentPoint)
 assume degrees everywhere.
 
 TanRaDecToPixel ()
 
AstrometryTransformLinear getLinPart () const
 The Linear part (corresponding to CD's and CRPIX's)
 
void setTangentPoint (Point const &tangentPoint)
 Resets the projection (or tangent) point.
 
Point getTangentPoint () const
 tangent point coordinates (degrees)
 
void apply (double xIn, double yIn, double &xOut, double &yOut) const
 
void transformPosAndErrors (const FatPoint &in, FatPoint &out) const
 transform with analytical derivatives
 
TanPixelToRaDec inverted () const
 exact typed inverse:
 
std::unique_ptr< AstrometryTransformroughInverse (const Frame &region) const
 Overload the "generic routine" (available for all AstrometryTransform types.
 
std::unique_ptr< AstrometryTransforminverseTransform (double precision, const Frame &region) const
 Inverse transform: returns a TanPixelToRaDec.
 
void print (std::ostream &out) const
 prints the transform coefficients to stream.
 
std::unique_ptr< AstrometryTransformclone () const
 returns a copy (allocated by new) of the transformation.
 
double fit (StarMatchList const &starMatchList)
 fits a transform to a std::list of Point pairs (p1,p2, the Point fields in StarMatch).
 
virtual void apply (double xIn, double yIn, double &xOut, double &yOut) const=0
 
void apply (Point const &in, Point &out) const
 applies the tranfo to in and writes into out. Is indeed virtual.
 
Point apply (Point const &in) const
 All these apply(..) shadow the virtual one in derived classes, unless one writes "using AstrometryTransform::apply".
 
Frame apply (Frame const &inputframe, bool inscribed) const
 Transform a bounding box, taking either the inscribed or circumscribed box.
 
std::string __str__ () const
 
void transformStar (FatPoint &in) const
 
virtual double getJacobian (Point const &point) const
 returns the local jacobian.
 
virtual double getJacobian (double x, double y) const
 returns the local jacobian.
 
virtual std::unique_ptr< AstrometryTransformcomposeAndReduce (AstrometryTransform const &right) const
 Return a reduced composition of newTransform = this(right()), or nullptr if it cannot be reduced.
 
virtual void computeDerivative (Point const &where, AstrometryTransformLinear &derivative, double step=0.01) const
 Computes the local Derivative of a transform, w.r.t.
 
virtual AstrometryTransformLinear linearApproximation (Point const &where, double step=0.01) const
 linear (local) approximation.
 
virtual void transformErrors (Point const &where, const double *vIn, double *vOut) const
 transform errors (represented as double[3] in order V(xx),V(yy),Cov(xy))
 
void getParams (double *params) const
 params should be at least Npar() long
 
void offsetParams (Eigen::VectorXd const &delta)
 
virtual double paramRef (Eigen::Index i) const
 
virtual double & paramRef (Eigen::Index i)
 
virtual void paramDerivatives (Point const &where, double *dx, double *dy) const
 Derivative w.r.t parameters.
 
virtual std::size_t getNpar () const
 returns the number of parameters (to compute chi2's)
 
virtual std::shared_ptr< ast::MappingtoAstMap (jointcal::Frame const &domain) const
 Create an equivalent AST mapping for this transformation, including an analytic inverse if possible.
 
void write (const std::string &fileName) const
 
virtual void write (std::ostream &stream) const
 

Detailed Description

This one is the Tangent Plane (called gnomonic) projection (from celestial sphere to tangent plane)

this transform does not implement corrections, since they are defined the other way around (from pixels to sky), and not invertible analytically. The inversion of tangent point WCS (TanPixelToRaDec) is obtained via inverseTransform().

Definition at line 707 of file AstrometryTransform.h.

Constructor & Destructor Documentation

◆ TanRaDecToPixel() [1/2]

lsst::jointcal::TanRaDecToPixel::TanRaDecToPixel ( AstrometryTransformLinear tan2Pix,
Point const & tangentPoint )

assume degrees everywhere.

Definition at line 1660 of file AstrometryTransform.cc.

1661 : linTan2Pix(std::move(tan2Pix)) {
1662 setTangentPoint(tangentPoint);
1663}
void setTangentPoint(Point const &tangentPoint)
Resets the projection (or tangent) point.
T move(T... args)

◆ TanRaDecToPixel() [2/2]

lsst::jointcal::TanRaDecToPixel::TanRaDecToPixel ( )

Definition at line 1674 of file AstrometryTransform.cc.

1674 : linTan2Pix() {
1675 ra0 = dec0 = 0;
1676 cos0 = 1;
1677 sin0 = 0;
1678}

Member Function Documentation

◆ __str__()

std::string lsst::jointcal::AstrometryTransform::__str__ ( ) const
inlineinherited

Definition at line 94 of file AstrometryTransform.h.

94 {
96 print(s);
97 return s.str();
98 }
virtual void print(std::ostream &out) const =0
prints the transform coefficients to stream.

◆ apply() [1/5]

void lsst::jointcal::TanRaDecToPixel::apply ( double xIn,
double yIn,
double & xOut,
double & yOut ) const
virtual

Implements lsst::jointcal::AstrometryTransform.

Definition at line 1737 of file AstrometryTransform.cc.

1737 {
1738 double ra = deg2rad(xIn);
1739 double dec = deg2rad(yIn);
1740 if (ra - ra0 > M_PI) ra -= (2. * M_PI);
1741 if (ra - ra0 < -M_PI) ra += (2. * M_PI);
1742 // Code inspired from worldpos.c in wcssubs (ancestor of the wcslib)
1743 // The same code is copied in ::transformPosAndErrors()
1744 double coss = std::cos(dec);
1745 double sins = std::sin(dec);
1746 double l = std::sin(ra - ra0) * coss;
1747 double m = sins * sin0 + coss * cos0 * std::cos(ra - ra0);
1748 l = l / m;
1749 m = (sins * cos0 - coss * sin0 * std::cos(ra - ra0)) / m;
1750 // l and m are now coordinates in the tangent plane, in radians.
1751 l = rad2deg(l);
1752 m = rad2deg(m);
1753 linTan2Pix.apply(l, m, xOut, yOut);
1754}
#define M_PI
Definition ListMatch.cc:31
double dec
Definition Match.cc:41
int m
Definition SpanSet.cc:48
void apply(double xIn, double yIn, double &xOut, double &yOut) const override
T cos(T... args)
T sin(T... args)

◆ apply() [2/5]

virtual void lsst::jointcal::AstrometryTransform::apply ( double xIn,
double yIn,
double & xOut,
double & yOut ) const
virtual

◆ apply() [3/5]

Frame lsst::jointcal::AstrometryTransform::apply ( Frame const & inputframe,
bool inscribed ) const

Transform a bounding box, taking either the inscribed or circumscribed box.

Parameters
[in]inputframeThe frame to be transformed.
[in]inscribedReturn the inscribed (true) or circumscribed (false) box.
Returns
The transformed frame.

Definition at line 89 of file AstrometryTransform.cc.

77 {
78 // 2 opposite corners
79 double xtmin1, xtmax1, ytmin1, ytmax1;
80 apply(inputframe.xMin, inputframe.yMin, xtmin1, ytmin1);
81 apply(inputframe.xMax, inputframe.yMax, xtmax1, ytmax1);
82 Frame fr1(std::min(xtmin1, xtmax1), std::min(ytmin1, ytmax1), std::max(xtmin1, xtmax1),
83 std::max(ytmin1, ytmax1));
84 // 2 other corners
85 double xtmin2, xtmax2, ytmin2, ytmax2;
86 apply(inputframe.xMin, inputframe.yMax, xtmin2, ytmax2);
87 apply(inputframe.xMax, inputframe.yMin, xtmax2, ytmin2);
88 Frame fr2(std::min(xtmin2, xtmax2), std::min(ytmin2, ytmax2), std::max(xtmin2, xtmax2),
89 std::max(ytmin2, ytmax2));
90
91 if (inscribed) return fr1 * fr2;
92 return fr1 + fr2;
93}
void apply(double xIn, double yIn, double &xOut, double &yOut) const
T max(T... args)
T min(T... args)

◆ apply() [4/5]

Point lsst::jointcal::AstrometryTransform::apply ( Point const & in) const
inline

All these apply(..) shadow the virtual one in derived classes, unless one writes "using AstrometryTransform::apply".

Definition at line 75 of file AstrometryTransform.h.

75 {
76 double xout, yout;
77 apply(in.x, in.y, xout, yout);
78 return Point(xout, yout);
79 }

◆ apply() [5/5]

void lsst::jointcal::AstrometryTransform::apply ( Point const & in,
Point & out ) const
inline

applies the tranfo to in and writes into out. Is indeed virtual.

Definition at line 71 of file AstrometryTransform.h.

71{ apply(in.x, in.y, out.x, out.y); }

◆ clone()

std::unique_ptr< AstrometryTransform > lsst::jointcal::TanRaDecToPixel::clone ( ) const
virtual

returns a copy (allocated by new) of the transformation.

Implements lsst::jointcal::AstrometryTransform.

Definition at line 1776 of file AstrometryTransform.cc.

◆ composeAndReduce()

std::unique_ptr< AstrometryTransform > lsst::jointcal::AstrometryTransform::composeAndReduce ( AstrometryTransform const & right) const
virtualinherited

Return a reduced composition of newTransform = this(right()), or nullptr if it cannot be reduced.

"Reduced" in this context means that they are capable of being merged into a single transform, for example, for two polynomials:

\[ f(x) = 1 + x^2, g(x) = -1 + 3x \]

we would have h = f.composeAndReduce(g) == 2 - 6x + 9x^2.

To be overloaded by derived classes if they can properly reduce the composition.

Parameters
rightThe transform to apply first.
Returns
The new reduced and composed AstrometryTransform, or nullptr if no such reduction is possible.

Reimplemented in lsst::jointcal::AstrometryTransformPolynomial, lsst::jointcal::TanPixelToRaDec, and lsst::jointcal::AstrometryTransformIdentity.

Definition at line 95 of file AstrometryTransform.cc.

96 { // by default no way to compose
98}

◆ computeDerivative()

void lsst::jointcal::AstrometryTransform::computeDerivative ( Point const & where,
AstrometryTransformLinear & derivative,
double step = 0.01 ) const
virtualinherited

Computes the local Derivative of a transform, w.r.t.

the Derivative is represented by a AstrometryTransformLinear, in which (hopefully), the offset terms are zero.

position.

Step is used for numerical derivation.

Derivative should transform a vector of offsets into a vector of offsets.

Reimplemented in lsst::jointcal::AstrometryTransformIdentity, lsst::jointcal::AstrometryTransformPolynomial, and lsst::jointcal::AstrometryTransformLinear.

Definition at line 119 of file AstrometryTransform.cc.

120 {
121 double x = where.x;
122 double y = where.y;
123 double xp0, yp0;
124 apply(x, y, xp0, yp0);
125
126 double xp, yp;
127 apply(x + step, y, xp, yp);
128 derivative.a11() = (xp - xp0) / step;
129 derivative.a21() = (yp - yp0) / step;
130 apply(x, y + step, xp, yp);
131 derivative.a12() = (xp - xp0) / step;
132 derivative.a22() = (yp - yp0) / step;
133 derivative.dx() = 0;
134 derivative.dy() = 0;
135}
int const step
int y
Definition SpanSet.cc:48
virtual void apply(double xIn, double yIn, double &xOut, double &yOut) const =0

◆ fit()

double lsst::jointcal::TanRaDecToPixel::fit ( StarMatchList const & starMatchList)
virtual

fits a transform to a std::list of Point pairs (p1,p2, the Point fields in StarMatch).

After the fit this(p1) yields approximately p2. The returned value is the sum of squared residuals. If you want to fit a partial transform (e.g. such that this(T1(p1)) = T2(p2), use StarMatchList::applyTransform beforehand.

Implements lsst::jointcal::AstrometryTransform.

Definition at line 1780 of file AstrometryTransform.cc.

1780 {
1781 throw LSST_EXCEPT(pex::exceptions::InvalidParameterError,
1782 "TanRaDecToPixel::fit is NOT implemented (although it is doable)) ");
1783 return -1;
1784}
#define LSST_EXCEPT(type,...)
Create an exception with a given type.
Definition Exception.h:48

◆ getJacobian() [1/2]

double lsst::jointcal::AstrometryTransform::getJacobian ( double x,
double y ) const
virtualinherited

returns the local jacobian.

Definition at line 100 of file AstrometryTransform.cc.

100 {
101 double x2, y2;
102 double eps = x * 0.01;
103 if (eps == 0) eps = 0.01;
104 apply(x, y, x2, y2);
105 double dxdx, dydx;
106 apply(x + eps, y, dxdx, dydx);
107 dxdx -= x2;
108 dydx -= y2;
109 double dxdy, dydy;
110 apply(x, y + eps, dxdy, dydy);
111 dxdy -= x2;
112 dydy -= y2;
113 return ((dxdx * dydy - dxdy * dydx) / (eps * eps));
114}

◆ getJacobian() [2/2]

virtual double lsst::jointcal::AstrometryTransform::getJacobian ( Point const & point) const
inlinevirtualinherited

returns the local jacobian.

Definition at line 110 of file AstrometryTransform.h.

110{ return getJacobian(point.x, point.y); }
virtual double getJacobian(Point const &point) const
returns the local jacobian.

◆ getLinPart()

AstrometryTransformLinear lsst::jointcal::TanRaDecToPixel::getLinPart ( ) const

The Linear part (corresponding to CD's and CRPIX's)

Definition at line 1682 of file AstrometryTransform.cc.

1682{ return linTan2Pix; }

◆ getNpar()

virtual std::size_t lsst::jointcal::AstrometryTransform::getNpar ( ) const
inlinevirtualinherited

◆ getParams()

void lsst::jointcal::AstrometryTransform::getParams ( double * params) const
inherited

params should be at least Npar() long

Definition at line 217 of file AstrometryTransform.cc.

217 {
218 std::size_t npar = getNpar();
219 for (std::size_t i = 0; i < npar; ++i) params[i] = paramRef(i);
220}
virtual std::size_t getNpar() const
returns the number of parameters (to compute chi2's)
virtual double paramRef(Eigen::Index i) const

◆ getTangentPoint()

Point lsst::jointcal::TanRaDecToPixel::getTangentPoint ( ) const

tangent point coordinates (degrees)

Definition at line 1680 of file AstrometryTransform.cc.

1680{ return Point(rad2deg(ra0), rad2deg(dec0)); }

◆ inverseTransform()

std::unique_ptr< AstrometryTransform > lsst::jointcal::TanRaDecToPixel::inverseTransform ( double precision,
const Frame & region ) const
virtual

Inverse transform: returns a TanPixelToRaDec.

Reimplemented from lsst::jointcal::AstrometryTransform.

Definition at line 1771 of file AstrometryTransform.cc.

1771 {
1773 new TanPixelToRaDec(getLinPart().inverted(), getTangentPoint()));
1774}
Point getTangentPoint() const
tangent point coordinates (degrees)
TanPixelToRaDec inverted() const
exact typed inverse:
AstrometryTransformLinear getLinPart() const
The Linear part (corresponding to CD's and CRPIX's)

◆ inverted()

TanPixelToRaDec lsst::jointcal::TanRaDecToPixel::inverted ( ) const

exact typed inverse:

Definition at line 1756 of file AstrometryTransform.cc.

1756 {
1757 return TanPixelToRaDec(getLinPart().inverted(), getTangentPoint());
1758}

◆ linearApproximation()

AstrometryTransformLinear lsst::jointcal::AstrometryTransform::linearApproximation ( Point const & where,
double step = 0.01 ) const
virtualinherited

linear (local) approximation.

Reimplemented in lsst::jointcal::AstrometryTransformIdentity, and lsst::jointcal::AstrometryTransformLinear.

Definition at line 137 of file AstrometryTransform.cc.

138 {
139 Point outwhere = apply(where);
140 AstrometryTransformLinear der;
141 computeDerivative(where, der, step);
142 return AstrometryTransformLinearShift(outwhere.x, outwhere.y) * der *
143 AstrometryTransformLinearShift(-where.x, -where.y);
144}
virtual void computeDerivative(Point const &where, AstrometryTransformLinear &derivative, double step=0.01) const
Computes the local Derivative of a transform, w.r.t.

◆ offsetParams()

void lsst::jointcal::AstrometryTransform::offsetParams ( Eigen::VectorXd const & delta)
inherited

Definition at line 222 of file AstrometryTransform.cc.

222 {
223 std::size_t npar = getNpar();
224 for (std::size_t i = 0; i < npar; ++i) paramRef(i) += delta[i];
225}

◆ paramDerivatives()

void lsst::jointcal::AstrometryTransform::paramDerivatives ( Point const & where,
double * dx,
double * dy ) const
virtualinherited

Derivative w.r.t parameters.

Derivatives should be al least 2*NPar long. first Npar, for x, last Npar for y.

Reimplemented in lsst::jointcal::AstrometryTransformPolynomial.

Definition at line 237 of file AstrometryTransform.cc.

237 {
238 throw LSST_EXCEPT(pex::exceptions::InvalidParameterError,
239 "AstrometryTransform::paramDerivatives() should never be called ");
240}

◆ paramRef() [1/2]

double & lsst::jointcal::AstrometryTransform::paramRef ( Eigen::Index i)
virtualinherited

Reimplemented in lsst::jointcal::AstrometryTransformPolynomial.

Definition at line 232 of file AstrometryTransform.cc.

232 {
233 throw LSST_EXCEPT(pex::exceptions::InvalidParameterError,
234 "AstrometryTransform::paramRef should never be called ");
235}

◆ paramRef() [2/2]

double lsst::jointcal::AstrometryTransform::paramRef ( Eigen::Index i) const
virtualinherited

Reimplemented in lsst::jointcal::AstrometryTransformPolynomial.

Definition at line 227 of file AstrometryTransform.cc.

227 {
228 throw LSST_EXCEPT(pex::exceptions::InvalidParameterError,
229 std::string("AstrometryTransform::paramRef should never be called "));
230}

◆ print()

void lsst::jointcal::TanRaDecToPixel::print ( std::ostream & out) const
virtual

prints the transform coefficients to stream.

Implements lsst::jointcal::AstrometryTransform.

Definition at line 1760 of file AstrometryTransform.cc.

1760 {
1761 Point tp = getTangentPoint();
1762 stream << "tan2pix " << linTan2Pix << std::endl;
1763 stream << "tangent point " << tp.x << ' ' << tp.y << endl;
1764}
T endl(T... args)

◆ roughInverse()

std::unique_ptr< AstrometryTransform > lsst::jointcal::TanRaDecToPixel::roughInverse ( const Frame & region) const
virtual

Overload the "generic routine" (available for all AstrometryTransform types.

Reimplemented from lsst::jointcal::AstrometryTransform.

Definition at line 1766 of file AstrometryTransform.cc.

1766 {
1768 new TanPixelToRaDec(getLinPart().inverted(), getTangentPoint()));
1769}

◆ setTangentPoint()

void lsst::jointcal::TanRaDecToPixel::setTangentPoint ( Point const & tangentPoint)

Resets the projection (or tangent) point.

Definition at line 1665 of file AstrometryTransform.cc.

1665 {
1666 /* the radian to degrees conversion after projection
1667 is handled in apply */
1668 ra0 = deg2rad(tangentPoint.x);
1669 dec0 = deg2rad(tangentPoint.y);
1670 cos0 = std::cos(dec0);
1671 sin0 = std::sin(dec0);
1672}

◆ toAstMap()

virtual std::shared_ptr< ast::Mapping > lsst::jointcal::AstrometryTransform::toAstMap ( jointcal::Frame const & domain) const
inlinevirtualinherited

Create an equivalent AST mapping for this transformation, including an analytic inverse if possible.

Parameters
domainThe domain of the transform, to help find an inverse.
Returns
An AST Mapping that represents this transformation.

Reimplemented in lsst::jointcal::AstrometryTransformIdentity, and lsst::jointcal::AstrometryTransformPolynomial.

Definition at line 189 of file AstrometryTransform.h.

189 {
190 throw std::logic_error("toAstMap is not implemented for this class.");
191 }

◆ transformErrors()

void lsst::jointcal::AstrometryTransform::transformErrors ( Point const & where,
const double * vIn,
double * vOut ) const
virtualinherited

transform errors (represented as double[3] in order V(xx),V(yy),Cov(xy))

Definition at line 163 of file AstrometryTransform.cc.

163 {
164 AstrometryTransformLinear der;
165 computeDerivative(where, der, 0.01);
166 double a11 = der.A11();
167 double a22 = der.A22();
168 double a21 = der.A21();
169 double a12 = der.A12();
170
171 /* (a11 a12) (vxx vxy)
172 M = ( ) and V = ( )
173 (a21 a22) (xvy vyy)
174
175 Vxx = Vin[0], vyy = Vin[1], Vxy = Vin[2];
176 we want to compute M*V*tp(M)
177 A lin alg light package would be perfect...
178 */
179 int xx = 0;
180 int yy = 1;
181 int xy = 2;
182 // M*V :
183
184 double b11 = a11 * vIn[xx] + a12 * vIn[xy];
185 double b22 = a21 * vIn[xy] + a22 * vIn[yy];
186 double b12 = a11 * vIn[xy] + a12 * vIn[yy];
187 double b21 = a21 * vIn[xx] + a22 * vIn[xy];
188
189 // (M*V) * tp(M)
190
191 vOut[xx] = b11 * a11 + b12 * a12;
192 vOut[xy] = b11 * a21 + b12 * a22;
193 vOut[yy] = b21 * a21 + b22 * a22;
194}

◆ transformPosAndErrors()

void lsst::jointcal::TanRaDecToPixel::transformPosAndErrors ( const FatPoint & in,
FatPoint & out ) const
virtual

transform with analytical derivatives

Reimplemented from lsst::jointcal::AstrometryTransform.

Definition at line 1685 of file AstrometryTransform.cc.

1685 {
1686 /* this routine is very similar to apply, but also propagates errors.
1687 The deg2rad and rad2deg are ignored for errors because they act as
1688 2 global scalings that cancel each other.
1689 Derivatives were computed using maple:
1690
1691 l1 := sin(a - a0)*cos(d);
1692 m1 := sin(d)*sin(d0)+cos(d)*cos(d0)*cos(a-a0);
1693 l2 := sin(d)*cos(d0)-cos(d)*sin(d0)*cos(a-a0);
1694 simplify(diff(l1/m1,a));
1695 simplify(diff(l1/m1,d));
1696 simplify(diff(l2/m1,a));
1697 simplify(diff(l2/m1,d));
1698
1699 Checked against AstrometryTransform::transformPosAndErrors (dec 09)
1700 */
1701 double ra = deg2rad(in.x);
1702 double dec = deg2rad(in.y);
1703 if (ra - ra0 > M_PI) ra -= (2. * M_PI);
1704 if (ra - ra0 < -M_PI) ra += (2. * M_PI);
1705 // Code inspired from worldpos.c in wcssubs (ancestor of the wcslib)
1706 // The same code is copied in ::apply()
1707
1708 double coss = std::cos(dec);
1709 double sins = std::sin(dec);
1710 double sinda = std::sin(ra - ra0);
1711 double cosda = std::cos(ra - ra0);
1712 double l = sinda * coss;
1713 double m = sins * sin0 + coss * cos0 * cosda;
1714 l = l / m;
1715 m = (sins * cos0 - coss * sin0 * cosda) / m;
1716
1717 // derivatives
1718 double deno =
1719 sq(sin0) - sq(coss) + sq(coss * cos0) * (1 + sq(cosda)) + 2 * sins * sin0 * coss * cos0 * cosda;
1720 double a11 = coss * (cosda * sins * sin0 + coss * cos0) / deno;
1721 double a12 = -sinda * sin0 / deno;
1722 double a21 = coss * sinda * sins / deno;
1723 double a22 = cosda / deno;
1724
1725 FatPoint tmp;
1726 tmp.vx = a11 * (a11 * in.vx + 2 * a12 * in.vxy) + a12 * a12 * in.vy;
1727 tmp.vy = a21 * a21 * in.vx + a22 * a22 * in.vy + 2. * a21 * a22 * in.vxy;
1728 tmp.vxy = a21 * a11 * in.vx + a22 * a12 * in.vy + (a21 * a12 + a11 * a22) * in.vxy;
1729
1730 // l and m are now coordinates in the tangent plane, in radians.
1731 tmp.x = rad2deg(l);
1732 tmp.y = rad2deg(m);
1733
1734 linTan2Pix.transformPosAndErrors(tmp, out);
1735}
virtual void transformPosAndErrors(const FatPoint &in, FatPoint &out) const override
a mix of apply and Derivative

◆ transformStar()

void lsst::jointcal::AstrometryTransform::transformStar ( FatPoint & in) const
inlineinherited

Definition at line 107 of file AstrometryTransform.h.

107{ transformPosAndErrors(in, in); }
virtual void transformPosAndErrors(const FatPoint &in, FatPoint &out) const

◆ write() [1/2]

void lsst::jointcal::AstrometryTransform::write ( const std::string & fileName) const
inherited

Definition at line 247 of file AstrometryTransform.cc.

247 {
248 ofstream s(fileName.c_str());
249 write(s);
250 bool ok = !s.fail();
251 s.close();
252 if (!ok)
253 throw LSST_EXCEPT(pex::exceptions::InvalidParameterError,
254 "AstrometryTransform::write, something went wrong for file " + fileName);
255}
T c_str(T... args)
void write(const std::string &fileName) const

◆ write() [2/2]

void lsst::jointcal::AstrometryTransform::write ( std::ostream & stream) const
virtualinherited

Reimplemented in lsst::jointcal::AstrometryTransformIdentity, and lsst::jointcal::AstrometryTransformPolynomial.

Definition at line 257 of file AstrometryTransform.cc.

257 {
258 throw LSST_EXCEPT(
259 pex::exceptions::InvalidParameterError,
260 "AstrometryTransform::write(ostream), should never be called. MEans that it is missing in some "
261 "derived class ");
262}

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