LSST Applications g1653933729+a8ce1bb630,g171997e3ee+76e92115be,g1a997c3884+a8ce1bb630,g28da252d5a+4013ff5194,g2bbee38e9b+d6d0f9f6ae,g2bc492864f+d6d0f9f6ae,g2cdde0e794+ccb74358b7,g3156d2b45e+07302053f8,g347aa1857d+d6d0f9f6ae,g35bb328faa+a8ce1bb630,g3a166c0a6a+d6d0f9f6ae,g3e281a1b8c+130fae20e3,g4005a62e65+17cd334064,g414038480c+c9f68e2a12,g41af890bb2+3e1f62f438,g4e1a3235cc+9db7d56ad0,g7b55021d1b+7b623691d5,g80478fca09+334cc8d2bd,g82479be7b0+b568f6b267,g858d7b2824+37b39d8760,g9125e01d80+a8ce1bb630,ga5288a1d22+11cb34fefe,gae0086650b+a8ce1bb630,gb4ec7eb0ab+37b39d8760,gb58c049af0+d64f4d3760,gc081298178+284e133171,gc28159a63d+d6d0f9f6ae,gcf0d15dbbd+00fe2e0b07,gd6b7c0dfd1+8b62435e69,gda3e153d99+37b39d8760,gda6a2b7d83+00fe2e0b07,gdaeeff99f8+1711a396fd,gdd5a9049c5+23f3b3239a,ge2409df99d+5d9f551a54,ge33fd446bb+37b39d8760,ge79ae78c31+d6d0f9f6ae,gf0baf85859+2dea8344a2,gf5289d68f6+3777f3df5e,w.2024.41
LSST Data Management Base Package

Frame is used to represent a coordinate system. More...
#include <Frame.h>
Public Types  
using  ObjectPtr = std::unique_ptr<AstObject, Deleter> 
unique pointer holding an AST raw pointer  
Public Member Functions  
Frame (int naxes, std::string const &options="")  
Construct a Frame.  
virtual  ~Frame () 
Frame (Frame const &)=default  
Copy constructor: make a deep copy.  
Frame (Frame &&)=default  
Frame &  operator= (Frame const &)=delete 
Frame &  operator= (Frame &&)=default 
std::shared_ptr< Frame >  copy () const 
Return a deep copy of this object.  
double  angle (PointD const &a, PointD const &b, PointD const &c) const 
Find the angle at point B between the line joining points A and B, and the line joining points C and B.  
double  axAngle (PointD const &a, PointD const &b, int axis) const 
Find the angle, as seen from point A, between the positive direction of a specified axis, and the geodesic curve joining point A to point B.  
double  axDistance (int axis, double v1, double v2) const 
Return a signed value representing the axis increment from axis value v1 to axis value v2.  
double  axOffset (int axis, double v1, double dist) const 
Return an axis value formed by adding a signed axis increment onto a supplied axis value.  
std::shared_ptr< FrameSet >  convert (Frame const &to, std::string const &domainlist="") 
Compute a frameset that describes the conversion between this frame and another frame.  
double  distance (PointD const &point1, PointD const &point2) const 
Find the distance between two points whose Frame coordinates are given.  
std::shared_ptr< FrameSet >  findFrame (Frame const &tmplt, std::string const &domainlist="") 
Find a coordinate system with specified characteristics.  
std::string  format (int axis, double value) const 
Return a string containing the formatted (character) version of a coordinate value for a Frame axis.  
bool  getActiveUnit () const 
Get ActiveUnit: pay attention to units when one Frame is used to match another?  
std::string  getAlignSystem () const 
Get AlignSystem: the coordinate system used by convert and findFrame to align Frames.  
double  getBottom (int axis) const 
Get Bottom for one axis: the lowest axis value to display.  
int  getDigits () const 
Get Digits: the default used if no specific value specified for an axis.  
int  getDigits (int axis) const 
Get Digits for one axis.  
bool  getDirection (int axis) const 
Get Direction for one axis: display axis in conventional direction?  
std::string  getDomain () const 
Get Domain: coordinate system domain.  
double  getDut1 () const 
Get Dut1: difference between the UT1 and UTC timescale (sec)  
double  getEpoch () const 
Get Epoch: Epoch of observation.  
std::string  getFormat (int axis) const 
Get Format for one axis: format specification for axis values.  
std::string  getInternalUnit (int axis) const 
Get InternalUnit(axis) readonly attribute for one axis: physical units for unformated axis values.  
std::string  getLabel (int axis) const 
Get Label(axis) for one axis: axis label.  
bool  getMatchEnd () const 
Get MatchEnd: match trailing axes?  
int  getMaxAxes () const 
Get MaxAxes: the maximum axes a frame found by findFrame may have.  
int  getMinAxes () const 
Get MinAxes: the maximum axes a frame found by findFrame may have.  
int  getNAxes () const 
Get NAxes: the number of axes in the frame (i.e.  
std::string  getNormUnit (int axis) const 
Get NormUnit(axis) readonly attribute for one frame: normalised physical units for formatted axis values.  
double  getObsAlt () const 
Get ObsAlt: Geodetic altitude of observer (m).  
std::string  getObsLat () const 
Get ObsLat: Geodetic latitude of observer.  
std::string  getObsLon () const 
Get ObsLon: Geodetic longitude of observer.  
bool  getPermute () const 
Get Permute: allow axis permutation when used as a template?  
bool  getPreserveAxes () const 
Get PreserveAxes: preserve axes?  
std::string  getSymbol (int axis) const 
Get Symbol(axis) for one axis: axis symbol.  
std::string  getSystem () const 
Get System: coordinate system used to describe positions within the domain.  
std::string  getTitle () const 
Get Title: frame title.  
double  getTop (int axis) const 
Get Top: the highest axis value to display.  
std::string  getUnit (int axis) const 
Get Unit(axis) for one axis: physical units for formatted axis values.  
std::vector< double >  intersect (std::vector< double > const &a1, std::vector< double > const &a2, std::vector< double > const &b1, std::vector< double > const &b2) const 
Find the point of intersection between two geodesic curves.  
std::vector< int >  matchAxes (Frame const &other) const 
Look for corresponding axes between this frame and another.  
CmpFrame  under (Frame const &next) const 
Combine this frame with another to form a compound frame (CmpFrame), with the axes of this frame followed by the axes of the next frame.  
PointD  norm (PointD value) const 
Normalise a set of Frame coordinate values which might be unsuitable for display (e.g.  
PointD  offset (PointD point1, PointD point2, double offset) const 
Find the point which is offset a specified distance along the geodesic curve between two other points.  
DirectionPoint  offset2 (PointD const &point1, double angle, double offset) const 
Find the point which is offset a specified distance along the geodesic curve at a given angle from a specified starting point.  
void  permAxes (std::vector< int > perm) 
Permute the order in which a Frame's axes occur.  
FrameMapping  pickAxes (std::vector< int > const &axes) const 
Create a new Frame whose axes are copied from an existing Frame along with other Frame attributes, such as its Title.  
ResolvedPoint  resolve (std::vector< double > const &point1, std::vector< double > const &point2, std::vector< double > const &point3) const 
Resolve a vector into two orthogonal components.  
void  setAlignSystem (std::string const &system) 
Set AlignSystem: the coordinate system used by convert and findFrame to align Frames.  
void  setBottom (int axis, double bottom) 
Set Bottom: the lowest axis value to display.  
void  setDigits (int digits) 
Set Digits for all axes: number of digits of precision.  
void  setDigits (int axis, int digits) 
Set Digits for one axis: number of digits of precision.  
void  setDirection (bool direction, int axis) 
Set Direction for one axis: display axis in conventional direction?  
virtual void  setDomain (std::string const &domain) 
Set Domain: coordinate system domain.  
void  setDut1 (double dut1) 
Set Dut1: difference between the UT1 and UTC timescale (sec)  
void  setEpoch (double epoch) 
Set Epoch: Epoch of observation as a double (years)  
void  setEpoch (std::string const &epoch) 
Set Epoch: Epoch of observation as a string.  
void  setFormat (int axis, std::string const &format) 
Set Format for one axis: format specification for axis values.  
void  setLabel (int axis, std::string const &label) 
Set Label(axis) for one axis: axis label.  
void  setMatchEnd (bool match) 
Set MatchEnd: match trailing axes?  
void  setMaxAxes (int maxAxes) 
Get MaxAxes: the maximum number of axes a frame found by findFrame may have.  
void  setMinAxes (int minAxes) 
Get MinAxes: the minimum number of axes a frame found by findFrame may have.  
void  setObsAlt (double alt) 
Set ObsAlt: Geodetic altitude of observer (m).  
void  setObsLat (std::string const &lat) 
Set ObsLat: frame title.  
void  setObsLon (std::string const &lon) 
Set ObsLon: Geodetic longitude of observer.  
void  setActiveUnit (bool enable) 
Set ActiveUnit: pay attention to units when one Frame is used to match another?  
void  setPermute (bool permute) 
Set Permute: allow axis permutation when used as a template?  
void  setPreserveAxes (bool preserve) 
Set PreserveAxes: preserve axes?  
void  setSymbol (int axis, std::string const &symbol) 
Set Symbol(axis) for one axis: axis symbol.  
void  setSystem (std::string const &system) 
Set System: coordinate system used to describe positions within the domain.  
void  setTitle (std::string const &title) 
Set Title: frame title.  
void  setTop (int axis, double top) 
Set Top for one axis: the highest axis value to display.  
void  setUnit (int axis, std::string const &unit) 
Set Unit(axis) for one axis: physical units for formatted axis values.  
NReadValue  unformat (int axis, std::string const &str) const 
Read a formatted coordinate value (given as a character string) for a Frame axis and return the number of characters read and the value.  
int  getNIn () const 
Get NIn: the number of input axes.  
int  getNOut () const 
Get NOut: the number of output axes.  
bool  getIsSimple () const 
Get IsSimple: has the mapping been simplified?  
bool  isInverted () const 
Is this an inverted mapping?  
bool  getIsLinear () const 
Get IsLinear: is the Mapping linear?  
bool  getReport () const 
Get Report: report transformed coordinates to stdout?  
bool  hasForward () const 
Is the forward transform available?  
bool  hasInverse () const 
Is the inverse transform available?  
std::shared_ptr< Mapping >  inverted () const 
Get an inverse mapping.  
Array2D  linearApprox (PointD const &lbnd, PointD const &ubnd, double tol) const 
Compute a linear approximation to the forward transformation.  
SeriesMap  then (Mapping const &next) const 
Return a series compound mapping this(first(input)) containing shallow copies of the original.  
ParallelMap  under (Mapping const &next) const 
Return a parallel compound mapping containing shallow copies of the original.  
double  rate (PointD const &at, int ax1, int ax2) const 
Evaluate the rate of change of the Mapping with respect to a specified input, at a specified position.  
void  setReport (bool report) 
Set Report: report transformed coordinates to stdout?  
std::shared_ptr< Mapping >  simplified () const 
Return a simplied version of the mapping (which may be a compound Mapping such as a CmpMap).  
void  applyForward (ConstArray2D const &from, Array2D const &to) const 
Perform a forward transformation on 2D array, putting the results into a preallocated 2D array.  
Array2D  applyForward (ConstArray2D const &from) const 
Perform a forward transformation on a 2D array, returning the results as a new array.  
std::vector< double >  applyForward (std::vector< double > const &from) const 
Perform a forward transformation on a vector, returning the results as a new vector.  
void  applyInverse (ConstArray2D const &from, Array2D const &to) const 
Perform an inverse transformation on a 2D array, putting the results into a preallocated 2D array.  
Array2D  applyInverse (ConstArray2D const &from) const 
Perform an inverse transformation on a 2D array, returning the results as a new 2D array.  
std::vector< double >  applyInverse (std::vector< double > const &from) const 
Perform an inverse transformation on a vector, returning the results as a new vector.  
void  tranGridForward (PointI const &lbnd, PointI const &ubnd, double tol, int maxpix, Array2D const &to) const 
Transform a grid of points in the forward direction.  
Array2D  tranGridForward (PointI const &lbnd, PointI const &ubnd, double tol, int maxpix, int nPts) const 
Transform a grid of points in the inverse direction, returning the results as a new Array2D.  
void  tranGridInverse (PointI const &lbnd, PointI const &ubnd, double tol, int maxpix, Array2D const &to) const 
Transform a grid of points in the inverse direction.  
Array2D  tranGridInverse (PointI const &lbnd, PointI const &ubnd, double tol, int maxpix, int nPts) const 
Transform a grid of points in the inverse direction.  
bool  operator== (Object const &rhs) const 
Return True if this and rhs are the equal.  
bool  operator!= (Object const &rhs) const 
Return True if this and rhs are not equal.  
void  clear (std::string const &attrib) 
Clear the values of a specified set of attributes for an Object.  
bool  hasAttribute (std::string const &attrib) const 
Does this object have an attribute with the specified name?  
std::string  getClassName () const 
Get Class: the name of the class (e.g.  
std::string  getID () const 
Get ID: object identification string that is not copied.  
std::string  getIdent () const 
Get Ident: object identification string that is copied.  
int  getNObject () const 
Get NObject: number of AST objects in existence of the same type as the underlying AST class.  
int  getObjSize () const 
Get ObjSize: the inmemory size of the AST object in bytes.  
int  getRefCount () const 
Get RefCount: number of active pointers to the underlying AST object.  
bool  getUseDefs () const 
Get UseDefs: allow use of default values for Object attributes?  
void  lock (bool wait) 
Lock this object for exclusive use by the calling thread.  
bool  same (Object const &other) const 
Does this contain the same AST object as another?  
void  setID (std::string const &id) 
Set ID: object identification string that is not copied.  
void  setIdent (std::string const &ident) 
Set Ident: object identification string that is copied.  
void  setUseDefs (bool usedefs) 
Set UseDefs: allow use of default values for Object attributes?  
void  show (std::ostream &os, bool showComments=true) const 
Print a textual description the object to an ostream.  
std::string  show (bool showComments=true) const 
Return a textual description the object as a string.  
bool  test (std::string const &attrib) const 
Has this attribute been explicitly set (and not subsequently cleared)?  
void  unlock (bool report=false) 
Unlock this object previously locked using lock, so that other threads can use this object.  
AstObject const *  getRawPtr () const 
Get the raw AST pointer.  
AstObject *  getRawPtr () 
Get the raw AST pointer.  
Static Public Member Functions  
static std::shared_ptr< Object >  fromString (std::string const &str) 
Construct an Object from a string, using astFromString.  
template<typename Class >  
static std::shared_ptr< Class >  fromAstObject (AstObject *rawObj, bool copy) 
Given a bare AST object pointer return a shared pointer to an ast::Object of the correct type.  
Protected Member Functions  
Frame (AstFrame *rawPtr)  
Construct a Frame from a pointer to a raw AstFrame.  
virtual std::shared_ptr< Object >  copyPolymorphic () const override 
Return a deep copy of this object.  
template<typename Class >  
std::shared_ptr< Class >  decompose (int i, bool copy) const 
Return a deep copy of one of the two component mappings.  
template<typename T , typename AstT >  
std::shared_ptr< T >  copyImpl () const 
Implementation of deep copy.  
bool  getB (std::string const &attrib) const 
Get the value of an attribute as a bool.  
std::string const  getC (std::string const &attrib) const 
Get the value of an attribute as a string.  
double  getD (std::string const &attrib) const 
Get the value of an attribute as a double.  
float  getF (std::string const &attrib) const 
Get the value of an attribute as a float.  
int  getI (std::string const &attrib) const 
Get the value of an attribute as an int.  
long int  getL (std::string const &attrib) const 
Get the value of an attribute as a long int.  
void  set (std::string const &setting) 
Assign a set of attribute values, overriding any previous values.  
void  setB (std::string const &attrib, bool value) 
Set the value of an attribute as a bool.  
void  setC (std::string const &attrib, std::string const &value) 
Set the value of an attribute as a string.  
void  setD (std::string const &attrib, double value) 
Set the value of an attribute as a double.  
void  setF (std::string const &attrib, float value) 
Set the value of an attribute as a float.  
void  setI (std::string const &attrib, int value) 
Set the value of an attribute as an int.  
void  setL (std::string const &attrib, long int value) 
Set the value of an attribute as a long int.  
Static Protected Member Functions  
template<typename ShimT , typename AstT >  
static std::shared_ptr< ShimT >  makeShim (AstObject *p) 
Functor to make an astshim instance from a raw AST pointer of the corresponding type.  
Friends  
class  Object 
Frame is used to represent a coordinate system.
It does this in rather the same way that a frame around a graph describes the coordinate space in which data are plotted. Consequently, a Frame has a Title (string) attribute, which describes the coordinate space, and contains axes which in turn hold information such as Label and Units strings which are used for labelling (e.g.) graphical output. In general, however, the number of axes is not restricted to two.
Functions are available for converting Frame coordinate values into a form suitable for display, and also for calculating distances and offsets between positions within the Frame.
Frames may also contain knowledge of how to transform to and from related coordinate systems.
In addition to those provided by Mapping and Object, Frame provides the following attributes, where axis
is an axis number, starting from 1 and (axis)
may be omitted if the Frame has only one axis:

inherited 

inlineexplicit 
Construct a Frame.
[in]  naxes  The number of Frame axes (i.e. the number of dimensions of the coordinate space which the Frame describes). 
[in]  options  Commaseparated list of attribute assignments. 
Definition at line 168 of file Frame.h.

default 
Copy constructor: make a deep copy.

default 

inlineexplicitprotected 
Construct a Frame from a pointer to a raw AstFrame.
This method is public so subclasses can call it.
std::invalid_argument  if rawPtr is not an AstFrame 
TODO make protected and use friend class
Definition at line 1519 of file Frame.h.
Find the angle at point B between the line joining points A and B, and the line joining points C and B.
These lines will in fact be geodesic curves appropriate to the Frame in use. For instance, in SkyFrame, they will be great circles.
[in]  a  the coordinates of the first point 
[in]  b  the coordinates of the first second 
[in]  c  the coordinates of the first third 
std::invalid_argument  if a , b or c have the wrong length 
Definition at line 201 of file Frame.h.

inlineinherited 
Perform a forward transformation on a 2D array, returning the results as a new array.
[in]  from  input coordinates, with dimensions (nPts, nIn) 
Definition at line 268 of file Mapping.h.

inlineinherited 

inlineinherited 
Perform a forward transformation on a vector, returning the results as a new vector.
[in]  from  input coordinates as a vector, with axes adjacent, e.g. x0, y0, x1, y1...xn, yn 
Definition at line 280 of file Mapping.h.

inlineinherited 
Perform an inverse transformation on a 2D array, returning the results as a new 2D array.
[in]  from  output coordinates, with dimensions (nPts, nOut) 

inlineinherited 
Perform an inverse transformation on a 2D array, putting the results into a preallocated 2D array.
[in]  from  input coordinates, with dimensions (nPts, nOut) 
[out]  to  transformed coordinates, with dimensions (nPts, nIn) 
Definition at line 294 of file Mapping.h.

inlineinherited 
Perform an inverse transformation on a vector, returning the results as a new vector.
[in]  from  input coordinates as a vector, with axes adjacent, e.g. x0, y0, x1, y1...xn, yn 
Definition at line 314 of file Mapping.h.
Find the angle, as seen from point A, between the positive direction of a specified axis, and the geodesic curve joining point A to point B.
[in]  a  the coordinates of the first point 
[in]  b  the coordinates of the second point 
[in]  axis  the index of the axis from which the angle is to be measured, where 1 is the first axis 
std::invalid_argument  if a or b have the wrong length 
distance
method. Definition at line 229 of file Frame.h.

inline 
Return a signed value representing the axis increment from axis value v1 to axis value v2.
For a simple Frame, this is a trivial operation returning the difference between the two axis values. But for other derived classes of Frame (such as a SkyFrame) this is not the case.
[in]  axis  The index of the axis to which the supplied values refer. The first axis has index 1. 
[in]  v1  The first axis value. 
[in]  v2  The second axis value. 

inline 
Return an axis value formed by adding a signed axis increment onto a supplied axis value.
For a simple Frame, this is a trivial operation returning the sum of the two supplied values. But for other derived classes of Frame (such as a SkyFrame) this is not the case.
[in]  axis  The index of the axis to which the supplied values refer. The first axis has index 1. 
[in]  v1  The original axis value. 
[in]  dist  The axis increment to add to the original axis value. 

inlineinherited 
Clear the values of a specified set of attributes for an Object.
Clearing an attribute cancels any value that has previously been explicitly set for it, so that the standard default attribute value will subsequently be used instead. This also causes the astTest function to return the value zero for the attribute, indicating that no value has been set.
std::shared_ptr< FrameSet > ast::Frame::convert  (  Frame const &  to, 
std::string const &  domainlist = "" ) 
Compute a frameset that describes the conversion between this frame and another frame.
If conversion is possible, it returns a shared pointer to a FrameSet which describes the conversion and which may be used (as a Mapping) to transform coordinate values in either direction. Otherwise it returns an empty shared pointer.
The same function may also be used to determine how to convert between two FrameSets (or between a Frame and a FrameSet, or vice versa). This mode is intended for use when (for example) two images have been calibrated by attaching a FrameSet to each. convert
might then be used to search for a celestial coordinate system that both images have in common, and the result could then be used to convert between the pixel coordinates of both images â€“ having effectively used their celestial coordinate systems to align them.
When using FrameSets, there may be more than one possible intermediate coordinate system in which to perform the conversion (for instance, two FrameSets might both have celestial coordinates, detector coordinates, pixel coordinates, etc.). A commaseparated list of coordinate system domains may therefore be given which defines a priority order to use when selecting the intermediate coordinate system. The path used for conversion must go via an intermediate coordinate system whose Domain attribute matches one of the domains given. If conversion cannot be achieved using the first domain, the next one is considered, and so on, until success is achieved.
If the AlignSideBand attribute is nonzero, alignment occurs in the upper sideband expressed within the spectral system and standard of rest given by attributes AlignSystem and AlignStdOfRest
. If AlignSideBand
is zero, the two DSBSpecFrames are aligned as if they were simple SpecFrames (i.e. the SideBand is ignored).
This function applies to all Frames. Alignment occurs within the coordinate system given by attribute AlignSystem.
If either this object or to
is a FrameSet, then this method will attempt to convert from the coordinate system described by the current Frame of the "from" FrameSet to that described by the current Frame of the "to" FrameSet.
To achieve this, it will consider all of the Frames within each FrameSet as a possible way of reaching an intermediate coordinate system that can be used for the conversion. There is then the possibility that more than one conversion path may exist and, unless the choice is sufficiently restricted by the "domainlist" string, the sequence in which the Frames are considered can be important. In this case, the search for a conversion path proceeds as follows:
If conversion is possible, the Base attributes of the two FrameSets will be modified on exit to identify the Frames used to access the intermediate coordinate system which was finally accepted.
Note that it is possible to force a particular Frame within a FrameSet to be used as the basis for the intermediate coordinate system, if it is suitable, by (a) focussing attention on it by specifying its domain in the "domainlist" string, or (b) making it the base Frame, since this is always considered first.
Alignment occurs within the spectral system and standard of rest given by attributes AlignSystem and AlignStdOfRest
.
Alignment occurs within the time system and time scale given by attributes AlignSystem and AlignTimeScale
.
auto cvt = a.convert(b)
Obtain a FrameSet that converts between the coordinate systems represented by "a" and "b" (assumed to be Frames).
auto cvt = SkyFrame().convert(SkyFrame("Equinox=2005"))
Create a FrameSet which describes precession in the default FK5 celestial coordinate system between equinoxes J2000 (also the default) and J2005. The returned "cvt" FrameSet may be used to apply this precession correction to any number of coordinate values given in radians.
Note that the returned FrameSet also contains information about how to format coordinate values. This means that setting its Report attribute to 1 is a simple way to obtain printed output (formatted in sexagesimal notation) to show the coordinate values before and after conversion.
auto cvt = a.convert(b, "sky,detector,")
Create a FrameSet that converts between the coordinate systems represented by the current Frames of "a" and "b" (now assumed to be FrameSets), via the intermediate "SKY" coordinate system. This, by default, is the Domain associated with a celestial coordinate system represented by a SkyFrame.
If this fails (for example, because either FrameSet lacks celestial coordinate information), then the userdefined "DETECTOR" coordinate system is used instead. If this also fails, then all other possible ways of achieving conversion are considered before giving up.
The returned "cvt" FrameSet describes the conversion.
The Base attributes of the two FrameSet will be set by `ref convert to indicate which of their Frames was used for the intermediate coordinate system. This means that you can subsequently determine which coordinate system was used by enquiring the Domain attribute of either base Frame.
[in,out]  to  A Frame which represents the "destination" coordinate system. This is the coordinate system into which you wish to convert your coordinates. If a FrameSet is given, its current Frame (as determined by its Current attribute) is taken to describe the destination coordinate system. Note that the Base attribute of this FrameSet may be modified by this function to indicate which intermediate coordinate system was used. 
[in]  domainlist  A string containing a commaseparated list of Frame domains. This may be used to define a priority order for the different intermediate coordinate systems that might be used to perform the conversion. The function will first try to obtain a conversion by making use only of an intermediate coordinate system whose Domain attribute matches the first domain in this list. If this fails, the second domain in the list will be used, and so on, until conversion is achieved. A blank domain (e.g. two consecutive commas) indicates that all coordinate systems should be considered, regardless of their domains. 
Definition at line 31 of file Frame.cc.

inline 
Return a deep copy of this object.
Definition at line 182 of file Frame.h.

inlineprotectedinherited 

inlineoverrideprotectedvirtual 
Return a deep copy of this object.
This is called by copy.
Each subclass must override this method. The standard implementation is:
for example Frame implements this as:
Reimplemented from ast::Mapping.
Reimplemented in ast::CmpFrame, ast::FrameDict, ast::FrameSet, ast::SkyFrame, ast::SpecFrame, and ast::TimeFrame.
Definition at line 1527 of file Frame.h.

protectedinherited 
Return a deep copy of one of the two component mappings.
This is intended to be exposed by classes that need it (e.g. CmpMap, CmpFrame and TranMap) as operator[]
.
[in]  i  Index: 0 for the first mapping, 1 for the second 
[in]  copy  If true make a deep copy, else a shallow copy 
std::invalid_argument  if i is not 0 or 1. 
std::runtime_error  if this mapping is not a compound mapping. 
Definition at line 64 of file Mapping.cc.
Find the distance between two points whose Frame coordinates are given.
The distance calculated is that along the geodesic curve that joins the two points. For example, in a basic Frame, the distance calculated will be the Cartesian distance along the straight line joining the two points. For a more specialised Frame describing a sky coordinate system, however, it would be the distance along the great circle passing through two sky positions.
[in]  point1  The coordinates of the first point. 
[in]  point2  The coordinates of the second point. 
Definition at line 474 of file Frame.h.
std::shared_ptr< FrameSet > ast::Frame::findFrame  (  Frame const &  tmplt, 
std::string const &  domainlist = "" ) 
Find a coordinate system with specified characteristics.
Use a "template" Frame to search another Frame (or FrameSet) to identify a coordinate system which has a specified set of characteristics. If a suitable coordinate system can be found, the function returns a pointer to a FrameSet which describes the required coordinate system and how to convert coordinates to and from it.
This function is provided to help answer general questions about coordinate systems, such as typically arise when coordinate information is imported into a program as part of an initially unknown dataset. For example:
You can also use this function as a means of reconciling a user's preference for a particular coordinate system (for example, what type of axes to draw) with what is actually possible given the coordinate information available.
To perform a search, you supply a "target" Frame (or FrameSet) which represents the set of coordinate systems to be searched. If a basic Frame is given as the target, this set of coordinate systems consists of the one described by this Frame, plus all other "virtual" coordinate systems which can potentially be reached from it by applying builtin conversions (for example, any of the celestial coordinate conversions known to the AST library would constitute a "builtin" conversion). If a FrameSet is given as the target, the set of coordinate systems to be searched consists of the union of those represented by all the individual Frames within it.
To select from this large set of possible coordinate systems, you supply a "template" Frame which is an instance of the type of Frame you are looking for. Effectively, you then ask the function to "find a coordinate system that looks like this".
You can make your request more or less specific by setting attribute values for the template Frame. If a particular attribute is set in the template, then the function will only find coordinate systems which have exactly the same value for that attribute. If you leave a template attribute unset, however, then the function has discretion about the value the attribute should have in any coordinate system it finds. The attribute will then take its value from one of the actual (rather than virtual) coordinate systems in the target. If the target is a FrameSet, its Current attribute will be modified to indicate which of its Frames was used for this purpose.
The result of this process is a coordinate system represented by a hybrid Frame which acquires some attributes from the template (but only if they were set) and the remainder from the target. This represents the "best compromise" between what you asked for and what was available. A Mapping is then generated which converts from the target coordinate system to this hybrid one, and the returned FrameSet encapsulates all of this information.
If the target is a FrameSet, the possibility exists that several of the Frames within it might be matched by the template. Unless the choice is sufficiently restricted by the "domainlist" string, the sequence in which Frames are searched can then become important. In this case, the search proceeds as follows:
If a suitable coordinate system is found, then the FrameSet's Current attribute will be modified to indicate which Frame was used to obtain attribute values which were not specified by the template. This Frame will, in some sense, represent the "closest" nonvirtual coordinate system to the one you requested.
auto result = target.findFrame(ast::Frame(3))
Search for a 3dimensional coordinate system in the target Frame (or FrameSet). No attributes have been set in the template Frame (created by ast::Frame), so no restriction has been placed on the required coordinate system, other than that it should have 3 dimensions. The first suitable Frame found will be returned as part of the "result" FrameSet.
auto result = target.findFrame(astSkyFrame())
Search for a celestial coordinate system in the target Frame (or FrameSet). The type of celestial coordinate system is unspecified, so astFindFrame will return the first one found as part of the "result" FrameSet. If the target is a FrameSet, then its Current attribute will be updated to identify the Frame that was used.
auto result = target.findFrame(astSkyFrame("MaxAxes=100"))
This is like the last example, except that in the event of the target being a CmpFrame, the component Frames encapsulated by the CmpFrame will be searched for a SkyFrame. If found, the returned Mapping will included a PermMap which selects the required axes from the target CmpFrame.
This is acomplished by setting the MaxAxes attribute of the template SkyFrame to a large number (larger than or equal to the number of axes in the target CmpFrame). This allows the SkyFrame to be used as a match for Frames containing from 2 to 100 axes.
auto result = target.findFrame(astSkyFrame("System=FK5"))
Search for an equatorial (FK5) coordinate system in the target. The Equinox
value for the coordinate system has not been specified, so will be obtained from the target. If the target is a FrameSet, its Current
attribute will be updated to indicate which SkyFrame was used to obtain this value.
auto result = target.findFrame(astFrame(2), "sky,pixel,")
Search for a 2dimensional coordinate system in the target. Initially, a search is made for a suitable coordinate system whose Domain attribute has the value "SKY". If this search fails, a search is then made for one with the domain "PIXEL". If this also fails, then any 2dimensional coordinate system is returned as part of the "result" FrameSet.
Only if no 2dimensional coordinate systems can be reached by applying builtin conversions to any of the Frames in the target will the search fail.
auto result = target.findFrame(astFrame(1, "Domain=WAVELENGTH"))
Searches for any 1dimensional coordinate system in the target which has the domain "WAVELENGTH".
auto result = target.findFrame(astFrame(1), "wavelength")
This example has exactly the same effect as that above. It illustrates the equivalence of the template's Domain attribute and the fields in the "domainlist" string.
auto result = target.findFrame(Frame(1, "MaxAxes=3"))
This is a more advanced example which will search for any coordinate system in the target having 1, 2 or 3 dimensions. The Frame returned (as part of the "result" FrameSet) will always be 1dimensional, but will be related to the coordinate system that was found by a suitable Mapping (e.g. a PermMap) which simply extracts the first axis.
If we had wanted a Frame representing the actual (1, 2 or 3dimensional) coordinate system found, we could set the PreserveAxes attribute to a nonzero value in the template.
auto result = target.findFrame(SkyFrame("Permute=0"))
Search for any celestial coordinate system in the target, but only finds one if its axes are in the conventional (longitude,latitude) order and have not been permuted (e.g. with astPermAxes).
A Frame (describing a coordinate system) will be found by this function if (a) it is "matched" by the template you supply, and (b) the value of its Domain attribute appears in the "domainlist" string (except that a blank field in this string permits any domain). A successful match by the template depends on a number of criteria, as outlined below:
[in,out]  tmplt  Template Frame, which should be an instance of the type of Frame you wish to find. If you wanted to find a Frame describing a celestial coordinate system, for example, then you might use a SkyFrame here. See the "Examples" section for more ideas. 
[in]  domainlist  String containing a commaseparated list of Frame domains. This may be used to establish a priority order for the different types of coordinate system that might be found. The function will first try to find a suitable coordinate system whose Domain attribute equals the first domain in this list. If this fails, the second domain in the list will be used, and so on, until a result is obtained. A blank domain (e.g. two consecutive commas) indicates that any coordinate system is acceptable (subject to the template) regardless of its domain. This list is caseinsensitive and all white space is ignored. If you do not wish to restrict the domain in this way, you should supply an empty string. 
This FrameSet will contain two Frames. Frame number 1 (its base Frame) represents the target coordinate system and will be the same as the (base Frame of the) target. Frame number 2 (its current Frame) will be a Frame representing the coordinate system which the function found. The Mapping which interrelates these two Frames will describe how to convert between their respective coordinate systems. Note that a FrameSet may be used both as a Mapping and as a Frame. If the result is used as a Mapping, then it provides a means of converting coordinates from the target coordinate system into the new coordinate system that was found (and vice versa if its inverse transformation is selected). If it is used as a Frame, its attributes will describe the new coordinate system.
tmpl
argument is not const because if it is a FrameSet then the BASE frame of the template may be changed. No other kind of frame will be altered.Domain
attribute of the template and then using a "domainlist" string which does not include the template's domain (or a blank field). If you do so, no coordinate system will be found. Definition at line 41 of file Frame.cc.

inline 
Return a string containing the formatted (character) version of a coordinate value for a Frame axis.
The formatting applied is determined by the Frame's attributes and, in particular, by any Format attribute string that has been set for the axis. A suitable default format (based on the Digits attribute value) will be applied if necessary.
[in]  axis  The number of the Frame axis for which formatting is to be performed (axis numbering starts at 1 for the first axis). 
[in]  value  The coordinate value to be formatted. 

staticinherited 
Given a bare AST object pointer return a shared pointer to an ast::Object of the correct type.
The returned object takes ownership of the pointer. This is almost always what you want, for instance astDecompose returns shallow copies of the internal pointers.
Class  The class of the returned shared pointer. (The actual class will be the correct class of rawPtr.) 
[in]  rawObj  A bare AST object pointer 
[in]  copy  If True then make a deep copy of the pointer (and free the original) 
Definition at line 138 of file Object.cc.

inlinestaticinherited 

inline 

inline 
Get AlignSystem: the coordinate system used by convert and findFrame to align Frames.
Definition at line 802 of file Frame.h.

inlineprotectedinherited 
Get the value of an attribute as a bool.
If possible, the attribute value is converted to the type you request.
std::runtime_error  if the attribute does not exist or the value cannot be converted 

inline 
Get Bottom for one axis: the lowest axis value to display.
Definition at line 807 of file Frame.h.

inlineprotectedinherited 
Get the value of an attribute as a string.
If possible, the attribute value is converted to the type you request.
std::runtime_error  if the attribute does not exist or the value cannot be converted 

inlineinherited 
Get Class: the name of the class (e.g.
Note: if AST returns "CmpMap" then the name will be changed to "SeriesMap" or "ParallelMap", as appropriate.
Definition at line 139 of file Object.h.

inlineprotectedinherited 
Get the value of an attribute as a double.
If possible, the attribute value is converted to the type you request.
std::runtime_error  if the attribute does not exist or the value cannot be converted 

inline 
Get Digits: the default used if no specific value specified for an axis.
Definition at line 812 of file Frame.h.

inline 

inline 
Get Direction for one axis: display axis in conventional direction?
Definition at line 822 of file Frame.h.

inline 

inline 

inline 

inlineprotectedinherited 
Get the value of an attribute as a float.
If possible, the attribute value is converted to the type you request.
std::runtime_error  if the attribute does not exist or the value cannot be converted 

inline 

protectedinherited 
Get the value of an attribute as an int.
If possible, the attribute value is converted to the type you request.
std::runtime_error  if the attribute does not exist or the value cannot be converted 

inlineinherited 

inlineinherited 

inline 
Get InternalUnit(axis) readonly attribute for one axis: physical units for unformated axis values.
Definition at line 848 of file Frame.h.

inlineinherited 

inlineinherited 

inlineprotectedinherited 
Get the value of an attribute as a long int.
If possible, the attribute value is converted to the type you request.
std::runtime_error  if the attribute does not exist or the value cannot be converted 

inline 

inline 

inline 

inline 

inline 

inlineinherited 

inlineinherited 

inline 
Get NormUnit(axis) readonly attribute for one frame: normalised physical units for formatted axis values.
Definition at line 882 of file Frame.h.

inlineinherited 

inlineinherited 

inline 

inline 

inline 

inline 

inline 

inlineinherited 

inlineinherited 

inlineinherited 

inlineinherited 

inline 

inline 

inline 

inline 

inline 
Get Unit(axis) for one axis: physical units for formatted axis values.
Definition at line 933 of file Frame.h.

inlineinherited 

inlineinherited 

inlineinherited 
Is the forward transform available?
hasForward
instead of getTranForward
for clarity, since it does not return a transform. Definition at line 114 of file Mapping.h.

inlineinherited 
Is the inverse transform available?
hasInverse
instead of getTranInverse
for clarity, since it does not return a transform. Definition at line 123 of file Mapping.h.
std::vector< double > ast::Frame::intersect  (  std::vector< double > const &  a1, 
std::vector< double > const &  a2,  
std::vector< double > const &  b1,  
std::vector< double > const &  b2 ) const 
Find the point of intersection between two geodesic curves.
For example, in a basic Frame, it will find the point of intersection between two straight lines. But for a SkyFrame it will find an intersection of two great circles.
[in]  a1  Coordinates of the first point on the first geodesic curve. 
[in]  a2  Coordinates of the second point on the first geodesic curve. 
[in]  b1  Coordinates of the first point on the second geodesic curve. 
[in]  b2  Coordinates of the second point on the second geodesic curve. 
std::runtime_error  if the frame is not 2dimensional 
a1
.nan
coordinate values if any of the input coordinates is invalid, or if the two points defining either geodesic are coincident, or if the two curves do not intersect.Definition at line 51 of file Frame.cc.

inherited 
Get an inverse mapping.
An inverse mapping is a deep copy of a mapping whose Invert attribute has been toggled, as indicated by isInverted. This swaps the meaning of "input" and "output", and of "forward" and "inverse". Thus it swaps the behavior of applyForward and applyInverse, getNIn and getNOut, hasForward and hasInverse and so on.
Note that the inverse mapping contains exactly the same model coefficients as the original, but they are used by applyInverse instead of applyForward. Thus for example if a ZoomMap has a zoom factor of 4.0 then its inverse also reports a zoom factor of 4.0 (despite behaving like an uninverted ZoomMap with zoom factor of 0.25).
Definition at line 41 of file Mapping.cc.

inlineinherited 

inherited 
Compute a linear approximation to the forward transformation.
[in]  lbnd  Input point defining the lower bounds of the box over which the linear approximation is computed. 
[in]  ubnd  Input point defining the upper bounds of the box over which the linear approximation is computed. 
[in]  tol  The maximum permitted deviation from linearity, expressed as apositive Cartesian displacement in the output coordinate space. If a linear fit to the forward transformation of the Mapping deviates from the true transformation by more than this amount at any point which is tested, then raise an exception. 
X_out = fit[0, 0] + fit[1, 0] X_in + fit[2, 0] Y_in Y_out = fit[0, 1] + fit[1, 1] X_in + fit[2, 1] Y_in Z_out = fit[0, 2] + fit[1, 2] X_in + fit[2, 2] Y_in
std::runtime_error  if the forward transformation cannot be modeled to within the specified tol . 
Definition at line 49 of file Mapping.cc.

inlineinherited 
Lock this object for exclusive use by the calling thread.
The threadsafe public interface to AST is designed so that an error is reported if any thread attempts to use an Object that it has not previously locked for its own exclusive use using this function. When an Object is created, it is initially locked by the thread that creates it, so newly created objects do not need to be explicitly locked. However, if an Object pointer is passed to another thread, the original thread must first unlock it (using astUnlock) and the new thread must then lock it (using astLock) before the new thread can use the Object.
[in]  wait  If the Object is curently locked by another thread then this function will either report an error or block. If a nonzero value is supplied for "wait", the calling thread waits until the object is available for it to use. Otherwise, an error is reported and the function returns immediately without locking the Object. 

inlinestaticprotectedinherited 
Functor to make an astshim instance from a raw AST pointer of the corresponding type.
ShimT  Output astshim class 
AstT  Output AST class 

inline 
Look for corresponding axes between this frame and another.
[in]  other  The other frame 
other
. Axis indices start at 1. A value of zero will be stored in the returned array for each axis in other
that has no corresponding axis in this frame. The number of elements in the array will be the number of axes in other
.Mapping
can be found between them using findFrame
or convert
. Thus, "corresponding axes" are not necessarily identical. For instance, SkyFrame
axes will match even if they describe different celestial coordinate systems. Definition at line 985 of file Frame.h.
Normalise a set of Frame coordinate values which might be unsuitable for display (e.g.
may lie outside the expected range) into a set of acceptable values suitable for display.
[in]  value  A point in the space which the Frame describes. 
value
. If any axes of value
lie outside the expected range for the Frame, the corresponding returned value is changed to a acceptable (normalised) value. Otherwise, the axes of value
are returned unchanged.norm
function of a specified Frame.Find the point which is offset a specified distance along the geodesic curve between two other points.
For example, in a basic Frame, this offset will be along the straight line joining two points. For a more specialised Frame describing a sky coordinate system, however, it would be along the great circle passing through two sky positions.
[in]  point1  The point marking the start of the geodesic curve. 
[in]  point2  The point marking the end of the geodesic curve. 
[in]  offset  The required offset from the first point along the geodesic curve. If this is positive, it will be towards the second point. If it is negative, it will be in the opposite direction. This offset need not imply a position lying between the two points given, as the curve will be extrapolated if necessary. 
distance
function.std::invalid_argument  if:

Definition at line 1075 of file Frame.h.

inline 
Find the point which is offset a specified distance along the geodesic curve at a given angle from a specified starting point.
This can only be used with 2dimensional Frames.
For example, in a basic Frame, this offset will be along the straight line joining two points. For a more specialised Frame describing a sky coordinate system, however, it would be along the great circle passing through two sky positions.
[in]  point1  The point marking the start of the geodesic curve. 
[in]  angle  The angle (in radians) from the positive direction of the second axis, to the direction of the required position, as seen from the starting position. Positive rotation is in the sense of rotation from the positive direction of axis 2 to the positive direction of axis 1. 
[in]  offset  The required offset from the first point along the geodesic curve. If this is positive, it will be in the direction of the given angle. If it is negative, it will be in the opposite direction. 
std::invalid_argument  if

Definition at line 1117 of file Frame.h.

inlineinherited 

inherited 
Return True if this and rhs
are the equal.
For two objects be equal, they both must have the same attributes and all contained objects must be equal.
Definition at line 85 of file Object.cc.

inline 
Permute the order in which a Frame's axes occur.
[in]  perm  A list of axes in their new order, using the current axis numbering. Axis numbers start at 1 for the first axis. Only genuine permutations of the axis order are permitted, so each axis must be referenced exactly once. 
When used on a FrameSet, the axes of the current frame are permuted and all connecting mappings are updated accordingly, so that current behavior is preserved (except for the new axis order for output data).
Definition at line 1138 of file Frame.h.
FrameMapping ast::Frame::pickAxes  (  std::vector< int > const &  axes  )  const 
Create a new Frame whose axes are copied from an existing Frame along with other Frame attributes, such as its Title.
Any number (zero or more) of the original Frame's axes may be copied, in any order, and additional axes with default attributes may also be included in the new Frame.
[in]  axes  the axes to be copied. These should be given in the order required in the new Frame, using the axis numbering in the original Frame (which starts at 1 for the first axis). Axes may be selected in any order, but each may only be used once. If additional (default) axes are also to be included, the corresponding elements of this array should be set to zero. 
Definition at line 68 of file Frame.cc.

inlineinherited 
Evaluate the rate of change of the Mapping with respect to a specified input, at a specified position.
The result is estimated by interpolating the function using a fourth order polynomial in the neighbourhood of the specified position. The size of the neighbourhood used is chosen to minimise the RMS residual per unit length between the interpolating polynomial and the supplied Mapping function. This method produces good accuracy but can involve evaluating the Mapping 100 or more times.
[in]  at  The input position at which the rate of change is to be evaluated. 
[in]  ax1  The index of the output for which the rate of change is to be found (1 for first output). 
[in]  ax2  The index of the input which is to be varied in order to find the rate of change (1 for the first input). 
ax1
with respect to input ax2
, evaluated at at
, or nan
if the value cannot be calculated. ResolvedPoint ast::Frame::resolve  (  std::vector< double > const &  point1, 
std::vector< double > const &  point2,  
std::vector< double > const &  point3 ) const 
Resolve a vector into two orthogonal components.
The vector from point 1 to point 2 is used as the basis vector. The vector from point 1 to point 3 is resolved into components parallel and perpendicular to this basis vector. The lengths of the two components are returned, together with the position of closest aproach of the basis vector to point 3.
[in]  point1  The start of the basis vector, and of the vector to be resolved. 
[in]  point2  The end of the basis vector. 
[in]  point3  The end of the vector to be resolved. 
nan
coordinate values if any of the input coordinates are invalid, or if the required output values are undefined.

inlineinherited 

inlineprotectedinherited 
Assign a set of attribute values, overriding any previous values.
The attributes and their new values are specified via a character string, which should contain a commaseparated list of the form: "attribute_1 = value_1, attribute_2 = value_2, ... " where "attribute_n" specifies an attribute name, and the value to the right of each " =" sign should be a suitable textual representation of the value to be assigned. This value will be interpreted according to the attribute's data type.
std::runtime_error  if the attribute is readonly 

inline 

inline 
Set AlignSystem: the coordinate system used by convert and findFrame to align Frames.
Definition at line 1203 of file Frame.h.

inlineprotectedinherited 
Set the value of an attribute as a bool.
If possible, the type you provide is converted to the actual type of the attribute.
std::runtime_error  if the attribute does not exist or the value cannot be converted 

inline 
Set Bottom: the lowest axis value to display.
Definition at line 1208 of file Frame.h.

inlineprotectedinherited 
Set the value of an attribute as a string.
If possible, the type you provide is converted to the actual type of the attribute.
std::runtime_error  if the attribute does not exist or the value cannot be converted 

inlineprotectedinherited 
Set the value of an attribute as a double.
If possible, the type you provide is converted to the actual type of the attribute.
std::runtime_error  if the attribute does not exist or the value cannot be converted 

inline 

inline 
Set Digits for all axes: number of digits of precision.
Definition at line 1213 of file Frame.h.

inline 
Set Direction for one axis: display axis in conventional direction?
Definition at line 1223 of file Frame.h.

inlinevirtual 
Set Domain: coordinate system domain.
Reimplemented in ast::FrameDict.
Definition at line 1230 of file Frame.h.

inline 

inline 

inline 

inlineprotectedinherited 
Set the value of an attribute as a float.
If possible, the type you provide is converted to the actual type of the attribute.
std::runtime_error  if the attribute does not exist or the value cannot be converted 

inline 
Set Format for one axis: format specification for axis values.
Definition at line 1250 of file Frame.h.

inlineprotectedinherited 
Set the value of an attribute as an int.
If possible, the type you provide is converted to the actual type of the attribute.
std::runtime_error  if the attribute does not exist or the value cannot be converted 

inlineinherited 

inlineinherited 

inlineprotectedinherited 
Set the value of an attribute as a long int.
If possible, the type you provide is converted to the actual type of the attribute.
std::runtime_error  if the attribute does not exist or the value cannot be converted 

inline 

inline 

inline 

inline 

inline 

inline 

inline 

inline 

inline 

inlineinherited 

inline 
Set Symbol(axis) for one axis: axis symbol.

inline 

inline 

inline 

inline 
Set Unit(axis) for one axis: physical units for formatted axis values.
Definition at line 1336 of file Frame.h.

inlineinherited 

inherited 
Return a textual description the object as a string.
[in]  showComments  Show comments? 

inherited 
Print a textual description the object to an ostream.
[in,out]  os  The stream to which to write the string representation. 
[in]  showComments  Show comments? 
Definition at line 158 of file Object.cc.

inlineinherited 
Return a simplied version of the mapping (which may be a compound Mapping such as a CmpMap).
Simplification eliminates redundant computational steps and merges separate steps which can be performed more efficiently in a single operation. As a simple example, a Mapping which multiplied coordinates by 5, and then multiplied the result by 10, could be simplified to a single step which multiplied by 50. Similarly, a Mapping which multiplied by 5, and then divided by 5, could be reduced to a simple copying operation.
This function should typically be applied to Mappings which have undergone substantial processing or have been formed by merging other Mappings. It is of potential benefit, for example, in reducing execution time if applied before using a Mapping to transform a large number of coordinates.

inlineinherited 
Has this attribute been explicitly set (and not subsequently cleared)?
false
.std::runtime_error  if an error results. 
Return a series compound mapping this(first(input)) containing shallow copies of the original.
[in]  next  the mapping whose input is the output of this mapping 
std::invalid_argument  if the number of input axes of next does not match the number of output axes of this mapping. 
Definition at line 37 of file Mapping.cc.

inlineinherited 
Transform a grid of points in the forward direction.
[in]  lbnd  The coordinates of the centre of the first pixel in the input grid along each dimension, size = nIn 
[in]  ubnd  The coordinates of the centre of the last pixel in the input grid along each dimension, size = nIn 
[in]  tol  The maximum tolerable geometrical distortion which may be introduced as a result of approximating nonlinear Mappings by a set of piecewise linear transformations. This should be expressed as a displacement within the output coordinate system of the Mapping. 
If piecewise linear approximation is not required, a value of zero may be given. This will ensure that the Mapping is used without any approximation, but may increase execution time.
If the value is too high, discontinuities between the linear approximations used in adjacent panel will be higher. If this is a problem, reduce the tolerance value used.
[in]  maxpix  A value which specifies an initial scale size (in input grid points) for the adaptive algorithm which approximates nonlinear Mappings with piecewise linear transformations. Normally, this should be a large value (larger than any dimension of the region of the input grid being used). In this case, a first attempt to approximate the Mapping by a linear transformation will be made over the entire input region. If a smaller value is used, the input region will first be divided into subregions whose size does not exceed " maxpix" grid points in any dimension. Only at this point will attempts at approximation commence. This value may occasionally be useful in preventing false convergence of the adaptive algorithm in cases where the Mapping appears approximately linear on large scales, but has irregularities (e.g. holes) on smaller scales. A value of, say, 50 to 100 grid points can also be employed as a safeguard in generalpurpose software, since the effect on performance is minimal. If too small a value is given, it will have the effect of inhibiting linear approximation altogether (equivalent to setting " tol" to zero). Although this may degrade performance, accurate results will still be obtained. 
[in]  to  Computed points, with dimensions (nPts, nOut), where nPts the desired number of points 
Definition at line 358 of file Mapping.h.

inlineinherited 
Transform a grid of points in the inverse direction, returning the results as a new Array2D.
See the overload of tranGridForward that outputs the data as the last argument for more information
Combine this frame with another to form a compound frame (CmpFrame), with the axes of this frame followed by the axes of the next
frame.
A compound frame allows two component Frames (of any class) to be merged together to form a more complex Frame. The axes of the two component Frames then appear together in the resulting CmpFrame (those of this Frame, followed by those of next
).
Since a CmpFrame is itself a Frame, it can be used as a component in forming further CmpFrames. Frames of arbitrary complexity may be built from simple individual Frames in this way.
Also since a Frame is a Mapping, a CmpFrame can also be used as a Mapping. Normally, a CmpFrame is simply equivalent to a UnitMap, but if either of the component Frames within a CmpFrame is a Region (a subclass of Frame), then the CmpFrame will use the Region as a Mapping when transforming values for axes described by the Region. Thus input axis values corresponding to positions which are outside the Region will result in bad output axis values.
The name comes the way vectors are sometimes shown for matrix multiplication: vertically, with the first axis at the bottom and the last axis at the top.
[in]  next  The next frame in the compound frame (the final next.getNAxes() axes) 
Definition at line 66 of file Frame.cc.

inherited 
Return a parallel compound mapping containing shallow copies of the original.
The resulting mapping has getNIn() + next.getNIn()
inputs and getNOut() + next.getNOut()
outputs. The first getNIn()
axes of input are transformed by this mapping, producing the first getNOut()
axes of output. The remaining axes of input are processed by next
, resulting in the remaining axes of output.
The name comes the way vectors are sometimes shown for matrix multiplication: vertically, with the first axis at the bottom and the last axis at the top.
[in]  next  the mapping that processes the final next.getNin() axes of input to produce the final next.getNout() axes of output. 
Definition at line 39 of file Mapping.cc.

inline 
Read a formatted coordinate value (given as a character string) for a Frame axis and return the number of characters read and the value.
The principle use of this function is in decoding usersupplied input which contains formatted coordinate values. Freeformat input is supported as far as possible. If input is ambiguous, it is interpreted with reference to the Frame's attributes (in particular, the Format string associated with the Frame's axis).
This function is, in essence, the inverse of astFormat.
Applicability:
Frame This function applies to all Frames. See the "Frame Input Format" section below for details of the input formats accepted by a basic Frame.
SkyFrame The SkyFrame class redefines the input format to be suitable for representing angles and times, with the resulting coordinate value returned in radians. See the "SkyFrame Input Format" section below for details of the formats accepted.
FrameSet The input formats accepted by a FrameSet are determined by its current Frame (as specified by the Current attribute).
Frame Input Format:
The input format accepted for a basic Frame axis is as follows:
Examples of acceptable Frame input formats include:
99
1.25
1.6
1E8
.99e17
<bad>
SkyFrame Input Format:
The input format accepted for a SkyFrame axis is as follows:
This final convention is intended to ensure that values formatted by Frame.format which contain less than three fields will be correctly interpreted if read back using Frame.unformat, even if they do not contain field identification characters.
Examples of acceptable SkyFrame input formats (with interpretation in parentheses) include:
001 : 02 : 03.4
(1d 02' 03.4" or 1h 02m 03.4s)
 <tt>22h 30</tt> (22h 30m 00s)
 <tt>136::10" (136d 00' 10" or 136h 00m 10s)
 `14M 27S` (0d 14' 27" or 0h 14m 27s):14:
(0d 14' 00" or 0h 14m 00s)
 `::4.1` (0d 00' 04.1" or 0h 00m 04.1s).9"</tt> (0d 00' 00.9")
`d12m` (0d 12' 00")
 <tt>H 12:22.3s</tt> (0h 12m 22.3s)
 <tt>\<bad\></tt> (<tt>AST__BAD</tt>)
Where alternative interpretations are shown, the choice of angle or
time depends on the associated Format(axis) attribute.
@param [in] axis The number of the Frame axis for which the coordinate value
is to be read (axis numbering starts at zero for the first axis).
@param [in] str String containing the formatted coordinate value.
@return an NReadValue containing the number of characters read and the value;
if nread is 0 then the value is certainly invalid.
<h3>Notes</h3>
 Any white space at the beginning of the string will be
skipped, as also will any trailing white space following the
coordinate value read. The number of characters read will reflect this.
 The number of characters will be 0 and the value undefined
if the string supplied does not contain a suitably formatted value.
 The string "<bad>" is recognised as a special case and will generate the value AST__BAD, without error. The test for this string is caseinsensitive and permits embedded white space.

inlineinherited 
Unlock this object previously locked using lock, so that other threads can use this object.
See lock for further details.
[in]  report  If true, an error will be reported if the supplied Object, or any Object contained within the supplied Object, is not currently locked by the running thread. If false, such Objects will be left unchanged, and no error will be reported. 