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casacore::DirectionCoordinate Class Reference

Interconvert pixel positions and directions (e.g. RA/DEC). More...

#include <DirectionCoordinate.h>

Inheritance diagram for casacore::DirectionCoordinate:
casacore::Coordinate

Public Member Functions

 DirectionCoordinate ()
 The default constructor creates a J2000 DirectionCoordinate with a CARtesion projection with longitude,latitude 0,0 at pixel 0,0 and an increment of +1 radian per pixel on both axes. More...
 
 DirectionCoordinate (MDirection::Types directionType, const Projection &projection, Double refLong, Double refLat, Double incLong, Double incLat, const Matrix< Double > &xform, Double refX, Double refY, Double longPole=999.0, Double latPole=999.0)
 Define the DirectionCoordinate transformation. More...
 
 DirectionCoordinate (MDirection::Types directionType, const Projection &projection, const Quantum< Double > &refLong, const Quantum< Double > &refLat, const Quantum< Double > &incLong, const Quantum< Double > &incLat, const Matrix< Double > &xform, Double refX, Double refY, const Quantum< Double > &longPole=Quantum< Double >(999.0, Unit("rad")), const Quantum< Double > &latPole=Quantum< Double >(999.0, Unit("rad")))
 Create DirectionCoordinate with Quantum-based interface. More...
 
 DirectionCoordinate (MDirection::Types directionType, const ::wcsprm &wcs, Bool oneRel=True)
 Constructor from WCS structure; must hold ONLY a celestial wcs structure Specify whether the absolute pixel coordinates in the wcs structure are 0- or 1-relative. More...
 
 DirectionCoordinate (const DirectionCoordinate &other)
 Copy constructor (copy semantics) More...
 
DirectionCoordinateoperator= (const DirectionCoordinate &other)
 Assignment (copy semantics). More...
 
virtual ~DirectionCoordinate ()
 Destructor. More...
 
virtual Coordinate::Type type () const
 Return Coordinate::DIRECTION. More...
 
virtual String showType () const
 Always returns the String "Direction". More...
 
virtual uInt nPixelAxes () const
 Always returns 2. More...
 
virtual uInt nWorldAxes () const
 
void setReferenceConversion (MDirection::Types type)
 Set extra conversion type. More...
 
void getReferenceConversion (MDirection::Types &type) const
 
virtual Bool toWorld (Vector< Double > &world, const Vector< Double > &pixel, Bool useConversionFrame=True) const
 Convert a pixel position to a world position or vice versa. More...
 
virtual Bool toPixel (Vector< Double > &pixel, const Vector< Double > &world) const
 world values must have units equivalent to the world axis units. More...
 
virtual Bool toMix (Vector< Double > &worldOut, Vector< Double > &pixelOut, const Vector< Double > &worldIn, const Vector< Double > &pixelIn, const Vector< Bool > &worldAxes, const Vector< Bool > &pixelAxes, const Vector< Double > &worldMin, const Vector< Double > &worldMax) const
 Mixed pixel/world coordinate conversion. More...
 
virtual Bool setWorldMixRanges (const IPosition &shape)
 Compute and retrieve the world min and max ranges, for use in function toMix, for a lattice of the given shape (for this coordinate). More...
 
virtual void setDefaultWorldMixRanges ()
 
void setWorldMixRanges (const Vector< Bool > &which, const Vector< Double > &world)
 Non-virtual function. More...
 
Bool toWorld (MDirection &world, const Vector< Double > &pixel) const
 A convenient way to turn the world vector into an MDirection or MVDirection for further processing in the Measures system. More...
 
Bool toPixel (Vector< Double > &pixel, const MDirection &world) const
 
Bool toWorld (MVDirection &world, const Vector< Double > &pixel) const
 
Bool toPixel (Vector< Double > &pixel, const MVDirection &world) const
 
MVDirection toWorld (const Vector< Double > &pixel) const
 
Vector< DoubletoPixel (const MVDirection &world) const
 
Vector< DoubletoPixel (const MDirection &world) const
 
virtual Bool toWorldMany (Matrix< Double > &world, const Matrix< Double > &pixel, Vector< Bool > &failures) const
 Batch up a lot of transformations. More...
 
virtual Bool toPixelMany (Matrix< Double > &pixel, const Matrix< Double > &world, Vector< Bool > &failures) const
 
virtual void makeWorldRelative (Vector< Double > &world) const
 Make absolute world coordinates relative and vice-versa (relative to the reference value). More...
 
virtual void makeWorldRelative (MDirection &world) const
 
virtual void makeWorldAbsolute (Vector< Double > &world) const
 
virtual void makeWorldAbsolute (MDirection &world) const
 
virtual void makeWorldAbsoluteRef (Vector< Double > &world, const Vector< Double > &refVal) const
 Make absolute coordinates relative and vice versa with respect to the given reference value. More...
 
MDirection::Types directionType (Bool showConversion=False) const
 Recover the requested attribute. More...
 
Projection projection () const
 
virtual Vector< StringworldAxisNames () const
 Return the requested attributed. More...
 
virtual Vector< StringworldAxisUnits () const
 
virtual Vector< DoublereferenceValue () const
 
virtual Vector< Doubleincrement () const
 
virtual Matrix< DoublelinearTransform () const
 
virtual Vector< DoublereferencePixel () const
 
virtual Bool setWorldAxisNames (const Vector< String > &names)
 Set the value of the requested attribute. More...
 
virtual Bool setReferencePixel (const Vector< Double > &refPix)
 
virtual Bool setLinearTransform (const Matrix< Double > &xform)
 
virtual Bool setIncrement (const Vector< Double > &inc)
 
virtual Bool setReferenceValue (const Vector< Double > &refval)
 
virtual Bool setWorldAxisUnits (const Vector< String > &units)
 Change the world axis units. More...
 
virtual Bool near (const Coordinate &other, Double tol=1e-6) const
 Comparison function. More...
 
virtual Bool near (const Coordinate &other, const Vector< Int > &excludeAxes, Double tol=1e-6) const
 
virtual void getPrecision (Int &precision, Coordinate::formatType &format, Bool showAsAbsolute, Int defPrecScientific, Int defPrecFixed, Int defPrecTime) const
 Format a DirectionCoordinate coordinate world value nicely through the common format interface. More...
 
virtual String format (String &units, Coordinate::formatType format, Double worldValue, uInt axis, Bool isAbsolute, Bool showAsAbsolute, Int precision=-1, Bool usePrecForMixed=False) const
 
Bool cylindricalFix (Int shapeLong, Int shapeLat)
 Fix cylindrical coordinates to put the longitude in [-180,180] range. More...
 
virtual CoordinatemakeFourierCoordinate (const Vector< Bool > &axes, const Vector< Int > &shape) const
 Find the Coordinate for when we Fourier Transform ourselves. More...
 
virtual Bool save (RecordInterface &container, const String &fieldName) const
 Save the DirectionCoordinate into the supplied record using the supplied field name. More...
 
virtual Coordinateclone () const
 Make a copy of the DirectionCoordinate using new. More...
 
Vector< DoublelongLatPoles () const
 Fish out the ref and non-native poles (refLong, refLat, longPole, latPole) Not for general use. More...
 
Quantity getPixelArea () const
 get the pixel area. More...
 
DirectionCoordinate convert (Quantity &angle, MDirection::Types directionType) const
 Convert this coordinate to another reference frame by rotating it about the reference pixel so the the axes of the new reference frame are aligned along the current pixel axes. More...
 
void setProjection (const Projection &)
 Set the projection. More...
 
void setReferenceFrame (const MDirection::Types rf)
 Set the base (as opposed to conversion) reference frame. More...
 
Bool hasSquarePixels () const
 Are the pixels square? More...
 
Bool isNCP () const
 Is the projection equivalent to NCP? More...
 
- Public Member Functions inherited from casacore::Coordinate
virtual ~Coordinate ()
 Destructor. More...
 
Vector< DoubleworldMixMin () const
 
Vector< DoubleworldMixMax () const
 
virtual void makePixelRelative (Vector< Double > &pixel) const
 Make absolute coordinates relative and vice-versa (with respect to the reference value). More...
 
virtual void makePixelAbsolute (Vector< Double > &pixel) const
 
virtual void makePixelRelativeMany (Matrix< Double > &pixel) const
 Batch up a lot of absolute/relative transformations. More...
 
virtual void makePixelAbsoluteMany (Matrix< Double > &pixel) const
 
virtual void makeWorldRelativeMany (Matrix< Double > &world) const
 
virtual void makeWorldAbsoluteMany (Matrix< Double > &world) const
 
const StringerrorMessage () const
 If the last conversion to world or pixel coordinates resulted in an error, report that error. More...
 
String formatQuantity (String &units, Coordinate::formatType format, const Quantum< Double > &worldValue, uInt axis, Bool isAbsolute=True, Bool showAsAbsolute=True, Int precision=-1)
 
virtual Bool doNearPixel (const Coordinate &other, const Vector< Bool > &thisAxes, const Vector< Bool > &otherAxes, Double tol=1.0e-6) const
 Comparison only made for specified axes in this and other Coordinate The default implementation should be ok for all Coordinate types except Stokes and Quality... More...
 
virtual Coordinaterotate (const Quantum< Double > &angle) const
 return the result of rotating the coordinate clockwise through the specified angle. More...
 

Static Public Member Functions

static Vector< StringaxisNames (MDirection::Types type, Bool FITSName=False)
 Return canonical axis names for the given MDirection type, giving FITS names if desired. More...
 
static DirectionCoordinaterestore (const RecordInterface &container, const String &fieldName)
 Recover the DirectionCoordinate from a record. More...
 
- Static Public Member Functions inherited from casacore::Coordinate
static String typeToString (Coordinate::Type type)
 
static void set_wcs (::wcsprm &wcs)
 Call wcsset on the wcs structure. More...
 
static void init_wcs (::wcsprm &wcs, int naxis)
 Call wcsini on the wcs structure. More...
 
static void sub_wcs (const ::wcsprm &src, int &nsub, int axes[],::wcsprm &dst)
 Call wcssub on the src/dst pair. More...
 
static void copy_wcs (const ::wcsprm &src,::wcsprm &dst)
 Call wcssub on the src/dst pair with null nsub/axes. More...
 

Private Member Functions

void toCurrent (Vector< Double > &degrees) const
 Interconvert between the current units and wcs units (degrees) More...
 
void fromCurrent (Vector< Double > &current) const
 
void checkFormat (Coordinate::formatType &format, Bool absolute) const
 Check formatting types. More...
 
String formatLatitude (String &units, MVAngle &mVA, Bool absolute, Coordinate::formatType form, Int prec) const
 Format a latitude. More...
 
String formatLongitude (String &units, MVAngle &mVA, MDirection::GlobalTypes gtype, Bool absolute, Coordinate::formatType form, Int prec) const
 Format a longitude. More...
 
Bool toMix2 (Vector< Double > &out, const Vector< Double > &in, const Vector< Double > &minWorld, const Vector< Double > &maxWorld, Bool longIsWorld) const
 Mixed pixel/world coordinate conversion. More...
 
void initializeFactors ()
 Initialize unit conversion vectors and units. More...
 
void makeDirectionCoordinate (MDirection::Types directionType, const Projection &proj, Double refLong, Double refLat, Double incLong, Double incLat, const Matrix< Double > &xform, Double refX, Double refY, Double longPole, Double latPole)
 Helper functions interfacing to WCS. More...
 
void makeWCS (::wcsprm &wcs, const Matrix< Double > &xform, const Projection &proj, MDirection::Types directionType, Double refPixLong, Double refPixLat, Double refLong, Double refLat, Double incLong, Double incLat, Double longPole, Double latPole)
 
void normalizePCMatrix ()
 Normalize each row of the PC matrix such that increment() will return the actual angular increment and any scale factors are removed from the PC matrix (modifies wcs_p.pc and wcs_p.cdelt and wcs_p.altlin, executes set_wcs() and hence wcsset() on the struct) See Greisen & Calabretta, A&A 395, 1061-1075 (2002), equation (4) More...
 
Double putLongInPiRange (Double lon, const String &unit) const
 
void makeConversionMachines ()
 Set up conversion machine. More...
 
virtual void convertTo (Vector< Double > &world) const
 Convert from type_p -> conversionType_p. More...
 
virtual void convertFrom (Vector< Double > &world) const
 
void copy (const DirectionCoordinate &other)
 Copy private data. More...
 
void setRotationMatrix ()
 Set up the offset coordinate rotation matrix. More...
 
void setRotationMatrix (RotMatrix &rot, Double lon, Double lat) const
 
const Vector< DoubletoCurrentFactors () const
 Return unit conversion vector for converting to current units. More...
 

Private Attributes

MDirection::Types type_p
 Direction type. More...
 
MDirection::Types conversionType_p
 
Projection projection_p
 Projection parameters. More...
 
mutable::wcsprm wcs_p
 WCS structure. More...
 
Vector< Doubleto_degrees_p
 WCS computes in degrees - use this to convert back and forth between current DirectionCoordinate units and degrees or radians. More...
 
Vector< Doubleto_radians_p
 
Vector< Stringnames_p
 Axis names. More...
 
Vector< Stringunits_p
 Current units. More...
 
RotMatrix rot_p
 Rotation matrix used to handle relative coordinates. More...
 
MDirection::ConvertpConversionMachineTo_p
 Conversion machines. More...
 
MDirection::ConvertpConversionMachineFrom_p
 

Additional Inherited Members

- Public Types inherited from casacore::Coordinate
enum  Type {
  LINEAR,
  DIRECTION,
  SPECTRAL,
  STOKES,
  TABULAR,
  QUALITY,
  COORDSYS
}
 This enum lists the types of the derived classes. More...
 
enum  formatType {
  DEFAULT,
  SCIENTIFIC,
  FIXED,
  MIXED,
  TIME
}
 This enum is used for formatting world values into Strings. More...
 
- Protected Member Functions inherited from casacore::Coordinate
 Coordinate ()
 Default constructor. More...
 
 Coordinate (const Coordinate &other)
 Copy constructor (copy semantics) More...
 
Coordinateoperator= (const Coordinate &other)
 Assignment (copy semantics) More...
 
void set_error (const String &errorMsg) const
 Set error message. More...
 
Bool find_scale_factor (String &error, Vector< Double > &factor, const Vector< String > &units, const Vector< String > &oldUnits)
 
void fourierUnits (String &nameOut, String &unitOut, String &unitInCanon, Coordinate::Type type, Int axis, const String &unitIn, const String &nameIn) const
 Tries to find a canonical unit for input unit (e.g. More...
 
Bool toWorldWCS (Vector< Double > &world, const Vector< Double > &pixel, wcsprm &wcs) const
 Functions to interconvert pixel<->world via wcs. More...
 
Bool toPixelWCS (Vector< Double > &pixel, const Vector< Double > &world, wcsprm &wcs) const
 
Bool toWorldManyWCS (Matrix< Double > &world, const Matrix< Double > &pixel, Vector< Bool > &failures, wcsprm &wcs) const
 
Bool toPixelManyWCS (Matrix< Double > &pixel, const Matrix< Double > &world, Vector< Bool > &failures, wcsprm &wcs) const
 
void toCurrentMany (Matrix< Double > &world, const Vector< Double > &toCurrentFactors) const
 Functions for handling conversion between the current units and the wcs units. More...
 
void fromCurrentMany (Matrix< Double > &world, const Vector< Double > &toCurrentFactors) const
 
void convertToMany (Matrix< Double > &world) const
 Functions for handling conversion between the current reference frame and the native one for many conversions. More...
 
void convertFromMany (Matrix< Double > &world) const
 
void pcToXform (Matrix< Double > &xForm, const wcsprm &wcs) const
 Interconvert between wcs PC cards and Matrix xForm format. More...
 
void xFormToPC (wcsprm &wcs, const Matrix< Double > &xForm) const
 
- Protected Attributes inherited from casacore::Coordinate
Vector< DoubleworldMin_p
 toMix ranges. More...
 
Vector< DoubleworldMax_p
 

Detailed Description

Interconvert pixel positions and directions (e.g. RA/DEC).

Intended use:

Public interface

Review Status

Reviewed By:
Peter Barnes
Date Reviewed:
1999/12/24
Test programs:
tDirectionCoordinate

Prerequisite

Synopsis

This class implements pixel to world coordinate conversions. This class implements geometric conversions (e.g. SIN projection) via the WCS library and also provides an interface to astronomical conversions (RA/DEC <–> l,b) via the Measures module.


Caution: All absolute pixels coordinates are zero relative;

Example

Let's make a DirectionCoordinate — used to represent a direction, usually an RA/DEC, but it could also be, e.g., an AZ/EL pair.

Matrix<Double> xform(2,2); // 1
xform = 0.0; xform.diagonal() = 1.0; // 2
Projection(Projection::SIN), // 4
135*C::pi/180.0, 60*C::pi/180.0, // 5
-1*C::pi/180.0, 1*C::pi/180, // 6
xform, // 7
128, 128); // 8

In this example is is more convenient to change the units to degrees. This can be accomplished as follows:

Vector<String> units(2); units = "deg"; // 9
radec.setWorldAxisUnits(units); // 10

The increment and reference value are updated appropriately.

Set up a couple of vectors to use the world and pixel coordinate values.

Vector<Double> world(2), pixel(2); // 11
pixel = 138.0; // 12

We use 138 as an arbitrary pixel position which is near the reference pixel so we can tell if the answers look foolish or not. We can actually perform a transformation like this as follows. If it succeeds we print the value of the world coordinate.

Bool ok = radec.toWorld(world, pixel); // 13
if (!ok) { // 14
cout << "Error: " << radec.errorMessage() << endl; // 15
return 1; // 16
} // 17
cout << world << " <--- " << pixel << endl; // 18

There is an overloaded "toWorld" function that produces an MDirection in case you want to, e.g., find out what the position in B1950 coordinates would be.

The reverse transformation takes place similarly:

ok = radec.toPixel(pixel, world); // 19

Example

We could also have made the above DirectionCoordinate using the Quantum-based constructor, which is a little more elegant if you want to use degrees.

Matrix<Double> xform(2,2); xform = 0.0; xform.diagonal() = 1.0; Quantum<Double> refLon(135.0, "deg"); Quantum<Double> refLat(60.0, "deg"); Quantum<Double> incLon(-1.0, "deg"); Quantum<Double> incLat(1.0, "deg"); DirectionCoordinate radec(MDirection::J2000, Projection(Projection::SIN), refLon, refLat, incLon, incLat, xform, 128, 128);

But note that the constructor will have converted the native units of the DirectionCoordinate to radians. So the Double-based toWorld and toPixel functions will be in terms of radians. If you want the native units to be degrees, then again you can use

Vector<String> units(2); units = "deg";
radec.setWorldAxisUnits(units);

and thereafter degrees are the native units.

Motivation

Directions in the sky are fundamental to astronomy.

Thrown Exceptions

To Do

Definition at line 217 of file DirectionCoordinate.h.

Constructor & Destructor Documentation

casacore::DirectionCoordinate::DirectionCoordinate ( )

The default constructor creates a J2000 DirectionCoordinate with a CARtesion projection with longitude,latitude 0,0 at pixel 0,0 and an increment of +1 radian per pixel on both axes.

casacore::DirectionCoordinate::DirectionCoordinate ( MDirection::Types  directionType,
const Projection projection,
Double  refLong,
Double  refLat,
Double  incLong,
Double  incLat,
const Matrix< Double > &  xform,
Double  refX,
Double  refY,
Double  longPole = 999.0,
Double  latPole = 999.0 
)

Define the DirectionCoordinate transformation.

refLong and refLat will normally the the RA/DEC of the pixel described by refX/refY. incLat/incLong are the increments per pixel (RA is usually negative), and the xform matrix is usually the unit diagonal matrix unless you have a rotation or some other linear transformation between the pixel and world axes.

Note that the units are radians initially. You can change it to degrees or something else with the setWorldAxisUnits method later if you want.

longPole and latPole are defined by Calabretta and Greisen (these are reference points not at the native pole). In general you can leave these out and the default values will cause them to be computed appropriately. However, when reading from FITS the LONPOLE and LATPOLE keywords are passed along here.

casacore::DirectionCoordinate::DirectionCoordinate ( MDirection::Types  directionType,
const Projection projection,
const Quantum< Double > &  refLong,
const Quantum< Double > &  refLat,
const Quantum< Double > &  incLong,
const Quantum< Double > &  incLat,
const Matrix< Double > &  xform,
Double  refX,
Double  refY,
const Quantum< Double > &  longPole = QuantumDouble >(999.0, Unit("rad")),
const Quantum< Double > &  latPole = QuantumDouble >(999.0, Unit("rad")) 
)

Create DirectionCoordinate with Quantum-based interface.

Parameters are the same as above. Regardless of the units of the quanta, the initial units of the DirectionCoordinate will be converted radians. You can change it to degrees or something else with the setWorldAxisUnits method later if you want.

longPole and latPole are defined by Calabretta and Greisen (these are reference points not at the native pole). In general you can leave these out and the default values will cause them to be computed appropriately. However, when reading from FITS the LONPOLE and LATPOLE keywords are passed along here. To get the default the 999.0 value should be used (units are irrelevant in that case)

casacore::DirectionCoordinate::DirectionCoordinate ( MDirection::Types  directionType,
const ::wcsprm &  wcs,
Bool  oneRel = True 
)

Constructor from WCS structure; must hold ONLY a celestial wcs structure Specify whether the absolute pixel coordinates in the wcs structure are 0- or 1-relative.

The coordinate is always constructed with 0-relative pixel coordinates

casacore::DirectionCoordinate::DirectionCoordinate ( const DirectionCoordinate other)

Copy constructor (copy semantics)

virtual casacore::DirectionCoordinate::~DirectionCoordinate ( )
virtual

Destructor.

Member Function Documentation

static Vector<String> casacore::DirectionCoordinate::axisNames ( MDirection::Types  type,
Bool  FITSName = False 
)
static

Return canonical axis names for the given MDirection type, giving FITS names if desired.

BEG think this should be in the MDirection class, but WNB disagrees. Leave it here for now.

void casacore::DirectionCoordinate::checkFormat ( Coordinate::formatType format,
Bool  absolute 
) const
private

Check formatting types.

virtual Coordinate* casacore::DirectionCoordinate::clone ( ) const
virtual

Make a copy of the DirectionCoordinate using new.

The caller is responsible for calling delete.

Implements casacore::Coordinate.

DirectionCoordinate casacore::DirectionCoordinate::convert ( Quantity angle,
MDirection::Types  directionType 
) const

Convert this coordinate to another reference frame by rotating it about the reference pixel so the the axes of the new reference frame are aligned along the current pixel axes.

The reference pixel remains the same and the conversion is exact for the reference pixel and in general becomes less accurate as distance from reference pixel increases. The latitude like and the longitude like pixel increments are preserved. Conversions which require extra information such as epoch and position are not supported. The angle parameter is the angle between the new coordinate and the pixel coordinate, measured clockwise from the positive y-axis of the new coordinate to the positive y-axis of the pixel coordinate; ie, it is the clockwise angle through which the current world coordinate would have to be rotated so that the new coordinate's axes would be parallel to the pixel axes. The accuracy of the returned angle is good to at least 7 digits.

virtual void casacore::DirectionCoordinate::convertFrom ( Vector< Double > &  world) const
privatevirtual

Reimplemented from casacore::Coordinate.

virtual void casacore::DirectionCoordinate::convertTo ( Vector< Double > &  world) const
privatevirtual

Convert from type_p -> conversionType_p.

Reimplemented from casacore::Coordinate.

void casacore::DirectionCoordinate::copy ( const DirectionCoordinate other)
private

Copy private data.

Bool casacore::DirectionCoordinate::cylindricalFix ( Int  shapeLong,
Int  shapeLat 
)

Fix cylindrical coordinates to put the longitude in [-180,180] range.

If False returned, it failed an an error is in errorMessage This fix is not done automatically internally because of the dependence on the image shape. It should be called for any foreign image (such as FITS) that is imported

MDirection::Types casacore::DirectionCoordinate::directionType ( Bool  showConversion = False) const

Recover the requested attribute.

virtual String casacore::DirectionCoordinate::format ( String units,
Coordinate::formatType  format,
Double  worldValue,
uInt  axis,
Bool  isAbsolute,
Bool  showAsAbsolute,
Int  precision = -1,
Bool  usePrecForMixed = False 
) const
virtual

Reimplemented from casacore::Coordinate.

String casacore::DirectionCoordinate::formatLatitude ( String units,
MVAngle mVA,
Bool  absolute,
Coordinate::formatType  form,
Int  prec 
) const
private

Format a latitude.

String casacore::DirectionCoordinate::formatLongitude ( String units,
MVAngle mVA,
MDirection::GlobalTypes  gtype,
Bool  absolute,
Coordinate::formatType  form,
Int  prec 
) const
private

Format a longitude.

void casacore::DirectionCoordinate::fromCurrent ( Vector< Double > &  current) const
private
Quantity casacore::DirectionCoordinate::getPixelArea ( ) const

get the pixel area.

virtual void casacore::DirectionCoordinate::getPrecision ( Int precision,
Coordinate::formatType format,
Bool  showAsAbsolute,
Int  defPrecScientific,
Int  defPrecFixed,
Int  defPrecTime 
) const
virtual

Format a DirectionCoordinate coordinate world value nicely through the common format interface.

See Coordinate for basics.

Formatting types that are allowed are SCIENTIFIC, FIXED, MIXED, and TIME If you ask for format type Coordinate::DEFAULT then the selected format depends upon what the value of the enum MDirection::GlobalTypes is for this DirectionCoordinate. For example, if it is GRADEC or GHADEC you would get Coordinate::TIME style formatting (DD:MM:SS.SS), otherwise you would get Coordinate::FIXED formatting by default.

axis says which axis in this Coordinate we are formatting. We have to know this because we may format Longitude and Latitude differently. For Coordinate::TIME style formatting, precision refers to the places after the decimal in the SS field.

If you leave units empty, then it makes up a nice unit for you.

Reimplemented from casacore::Coordinate.

void casacore::DirectionCoordinate::getReferenceConversion ( MDirection::Types type) const
inline

Definition at line 321 of file DirectionCoordinate.h.

References conversionType_p.

Bool casacore::DirectionCoordinate::hasSquarePixels ( ) const

Are the pixels square?

virtual Vector<Double> casacore::DirectionCoordinate::increment ( ) const
virtual

Implements casacore::Coordinate.

void casacore::DirectionCoordinate::initializeFactors ( )
private

Initialize unit conversion vectors and units.

Bool casacore::DirectionCoordinate::isNCP ( ) const

Is the projection equivalent to NCP?

virtual Matrix<Double> casacore::DirectionCoordinate::linearTransform ( ) const
virtual

Implements casacore::Coordinate.

Vector<Double> casacore::DirectionCoordinate::longLatPoles ( ) const

Fish out the ref and non-native poles (refLong, refLat, longPole, latPole) Not for general use.

Units are degrees.

void casacore::DirectionCoordinate::makeConversionMachines ( )
private

Set up conversion machine.

void casacore::DirectionCoordinate::makeDirectionCoordinate ( MDirection::Types  directionType,
const Projection proj,
Double  refLong,
Double  refLat,
Double  incLong,
Double  incLat,
const Matrix< Double > &  xform,
Double  refX,
Double  refY,
Double  longPole,
Double  latPole 
)
private

Helper functions interfacing to WCS.

virtual Coordinate* casacore::DirectionCoordinate::makeFourierCoordinate ( const Vector< Bool > &  axes,
const Vector< Int > &  shape 
) const
virtual

Find the Coordinate for when we Fourier Transform ourselves.

This pointer must be deleted by the caller. Axes specifies which axes of the Coordinate you wish to transform. Shape specifies the shape of the image associated with all the axes of the Coordinate. Currently the output reference pixel is always shape/2. If the pointer returned is 0, it failed with a message in errorMessage

Reimplemented from casacore::Coordinate.

void casacore::DirectionCoordinate::makeWCS ( ::wcsprm &  wcs,
const Matrix< Double > &  xform,
const Projection proj,
MDirection::Types  directionType,
Double  refPixLong,
Double  refPixLat,
Double  refLong,
Double  refLat,
Double  incLong,
Double  incLat,
Double  longPole,
Double  latPole 
)
private
virtual void casacore::DirectionCoordinate::makeWorldAbsolute ( Vector< Double > &  world) const
virtual

Reimplemented from casacore::Coordinate.

virtual void casacore::DirectionCoordinate::makeWorldAbsolute ( MDirection world) const
virtual
virtual void casacore::DirectionCoordinate::makeWorldAbsoluteRef ( Vector< Double > &  world,
const Vector< Double > &  refVal 
) const
virtual

Make absolute coordinates relative and vice versa with respect to the given reference value.

Add the other functions in this grouping as needed.

Reimplemented from casacore::Coordinate.

virtual void casacore::DirectionCoordinate::makeWorldRelative ( Vector< Double > &  world) const
virtual

Make absolute world coordinates relative and vice-versa (relative to the reference value).

Note that these functions are independent of the MDirection::Types (set either at construction or by function setReferenceConversion). The vectors must be of length nWorldAxes or memory access errors will occur

Reimplemented from casacore::Coordinate.

virtual void casacore::DirectionCoordinate::makeWorldRelative ( MDirection world) const
virtual
virtual Bool casacore::DirectionCoordinate::near ( const Coordinate other,
Double  tol = 1e-6 
) const
virtual

Comparison function.

Any private Double data members are compared with the specified fractional tolerance. Don't compare on the specified axes in the Coordinate. If the comparison returns False, method errorMessage returns a message about why.

Implements casacore::Coordinate.

virtual Bool casacore::DirectionCoordinate::near ( const Coordinate other,
const Vector< Int > &  excludeAxes,
Double  tol = 1e-6 
) const
virtual

Implements casacore::Coordinate.

void casacore::DirectionCoordinate::normalizePCMatrix ( )
private

Normalize each row of the PC matrix such that increment() will return the actual angular increment and any scale factors are removed from the PC matrix (modifies wcs_p.pc and wcs_p.cdelt and wcs_p.altlin, executes set_wcs() and hence wcsset() on the struct) See Greisen & Calabretta, A&A 395, 1061-1075 (2002), equation (4)

virtual uInt casacore::DirectionCoordinate::nPixelAxes ( ) const
virtual

Always returns 2.

Implements casacore::Coordinate.

virtual uInt casacore::DirectionCoordinate::nWorldAxes ( ) const
virtual

Implements casacore::Coordinate.

DirectionCoordinate& casacore::DirectionCoordinate::operator= ( const DirectionCoordinate other)

Assignment (copy semantics).

Projection casacore::DirectionCoordinate::projection ( ) const
Double casacore::DirectionCoordinate::putLongInPiRange ( Double  lon,
const String unit 
) const
private
virtual Vector<Double> casacore::DirectionCoordinate::referencePixel ( ) const
virtual

Implements casacore::Coordinate.

virtual Vector<Double> casacore::DirectionCoordinate::referenceValue ( ) const
virtual

Implements casacore::Coordinate.

static DirectionCoordinate* casacore::DirectionCoordinate::restore ( const RecordInterface container,
const String fieldName 
)
static

Recover the DirectionCoordinate from a record.

A null pointer means that the restoration did not succeed.

virtual Bool casacore::DirectionCoordinate::save ( RecordInterface container,
const String fieldName 
) const
virtual

Save the DirectionCoordinate into the supplied record using the supplied field name.

The field must not exist, otherwise False is returned.

Implements casacore::Coordinate.

virtual void casacore::DirectionCoordinate::setDefaultWorldMixRanges ( )
virtual

Reimplemented from casacore::Coordinate.

virtual Bool casacore::DirectionCoordinate::setIncrement ( const Vector< Double > &  inc)
virtual

Implements casacore::Coordinate.

virtual Bool casacore::DirectionCoordinate::setLinearTransform ( const Matrix< Double > &  xform)
virtual

Implements casacore::Coordinate.

void casacore::DirectionCoordinate::setProjection ( const Projection )

Set the projection.

void casacore::DirectionCoordinate::setReferenceConversion ( MDirection::Types  type)

Set extra conversion type.

Whenever a conversion from pixel to world is done, the world value is then further converted to this MDirection::Types value. For example, your DirectionCoordinate may be defined in J2000. You can use this to get the world values out in say GALACTIC. Similarly, whenever you convert from world to pixel, the world value is assumed to be that appropriate to the conversionDirectionType. It is first converted to the MDirection::Types with which the DirectionCoordinate was constructed and from there to pixel. If you don't call this function, or you set the same type for which the DirectionCoordinate was constructed, no extra conversions occur. Some conversions will fail. These are the ones that require extra frame information (epoch, position) such as to AZEL from J2000 etc. This will be added later.

In the mixed pixel/world conversion routine toMix the implementation is only partial. See the comments for this function below.

void casacore::DirectionCoordinate::setReferenceFrame ( const MDirection::Types  rf)

Set the base (as opposed to conversion) reference frame.

virtual Bool casacore::DirectionCoordinate::setReferencePixel ( const Vector< Double > &  refPix)
virtual

Implements casacore::Coordinate.

virtual Bool casacore::DirectionCoordinate::setReferenceValue ( const Vector< Double > &  refval)
virtual

Implements casacore::Coordinate.

void casacore::DirectionCoordinate::setRotationMatrix ( )
private

Set up the offset coordinate rotation matrix.

Units of long and lat are current world units

void casacore::DirectionCoordinate::setRotationMatrix ( RotMatrix rot,
Double  lon,
Double  lat 
) const
private
virtual Bool casacore::DirectionCoordinate::setWorldAxisNames ( const Vector< String > &  names)
virtual

Set the value of the requested attribute.

Note that these just change the internal values, they do not cause any recomputation.

Implements casacore::Coordinate.

virtual Bool casacore::DirectionCoordinate::setWorldAxisUnits ( const Vector< String > &  units)
virtual

Change the world axis units.

Adjust the increment and reference value by the ratio of the old and new units. The units must be compatible with angle. The units are initially "rad" (radians).

Implements casacore::Coordinate.

virtual Bool casacore::DirectionCoordinate::setWorldMixRanges ( const IPosition shape)
virtual

Compute and retrieve the world min and max ranges, for use in function toMix, for a lattice of the given shape (for this coordinate).

Using these ranges in toMix should speed it up and help avoid ambiguity. If the shape is negative, that indicates that the shape is unknown for that axis. The default range is used for that axis. This situation arises in a CoordinateSystem for which a pixel, but not a world axis has been removed. The output vectors are resized. Returns False if fails (and then setDefaultWorldMixRanges generates the ranges) with a reason in errorMessage(). The setDefaultWorldMixRanges function just gives you [-90->90], [-180,180] (in appropriate units)

Reimplemented from casacore::Coordinate.

void casacore::DirectionCoordinate::setWorldMixRanges ( const Vector< Bool > &  which,
const Vector< Double > &  world 
)

Non-virtual function.

When which is T, use the world value as the center for the mix world range.

virtual String casacore::DirectionCoordinate::showType ( ) const
virtual

Always returns the String "Direction".

Implements casacore::Coordinate.

void casacore::DirectionCoordinate::toCurrent ( Vector< Double > &  degrees) const
private

Interconvert between the current units and wcs units (degrees)

const Vector<Double> casacore::DirectionCoordinate::toCurrentFactors ( ) const
private

Return unit conversion vector for converting to current units.

virtual Bool casacore::DirectionCoordinate::toMix ( Vector< Double > &  worldOut,
Vector< Double > &  pixelOut,
const Vector< Double > &  worldIn,
const Vector< Double > &  pixelIn,
const Vector< Bool > &  worldAxes,
const Vector< Bool > &  pixelAxes,
const Vector< Double > &  worldMin,
const Vector< Double > &  worldMax 
) const
virtual

Mixed pixel/world coordinate conversion.

worldIn and worldAxes are of length nWorldAxes. pixelIn and pixelAxes are of length nPixelAxes. worldAxes(i)=True specifies you have given a world value in worldIn(i) to convert to pixel. pixelAxes(i)=True specifies you have given a pixel value in pixelIn(i) to convert to world. You cannot specify the same axis via worldAxes and pixelAxes. Values in pixelIn are converted to world and put into worldOut in the appropriate world axis location. Values in worldIn are copied to worldOut. Values in worldIn are converted to pixel and put into pixelOut in the appropriate pixel axis location. Values in pixelIn are copied to pixelOut.

worldMin and worldMax specify the range of the world coordinate (in the world axis units of that world axis in the CoordinateSystem) being solved for in a mixed calculation for each world axis. Some mixed solutions can be degenerate, whereupon you you must say which one you want. Use functions setWorldMixRanges and worldMixMin, worldMixMax to set these ranges, If you don't know, use the defaults (function setDefaultWorldMixRanges. Removed axes are handled (for example, a removed pixel axis with remaining corresponding world axis will correctly be converted to world using the replacement value). Returns True if the conversion succeeds, otherwise it returns False and errorMessage() contains an error message. The output vectors are resized.

If you actually request a pure pixel to world or world to pixel via toMix, then the functions toWorld or toPixel will be invoked directly (see above) and the extra conversion layer invoked through function setReferenceConversion will be active. However, if you request a true mixed pixel/world conversion, the extra conversion layer is not activated (because of the nature of mixed conversions). This situation may change in the future with a partial implementation added.

Reimplemented from casacore::Coordinate.

Bool casacore::DirectionCoordinate::toMix2 ( Vector< Double > &  out,
const Vector< Double > &  in,
const Vector< Double > &  minWorld,
const Vector< Double > &  maxWorld,
Bool  longIsWorld 
) const
private

Mixed pixel/world coordinate conversion.

Vector in must be length nWorldAxes (2). Specify whether longitude (in(0)) or latitude (in(1)) is the world coordinate. It is assumed that the other value is the pixel coordinate.

virtual Bool casacore::DirectionCoordinate::toPixel ( Vector< Double > &  pixel,
const Vector< Double > &  world 
) const
virtual

world values must have units equivalent to the world axis units.

If the coordinate has a conversion layer, the world coordinates must be supplied in the conversion frame.

Implements casacore::Coordinate.

Bool casacore::DirectionCoordinate::toPixel ( Vector< Double > &  pixel,
const MDirection world 
) const
Bool casacore::DirectionCoordinate::toPixel ( Vector< Double > &  pixel,
const MVDirection world 
) const
Vector<Double> casacore::DirectionCoordinate::toPixel ( const MVDirection world) const
Vector<Double> casacore::DirectionCoordinate::toPixel ( const MDirection world) const
virtual Bool casacore::DirectionCoordinate::toPixelMany ( Matrix< Double > &  pixel,
const Matrix< Double > &  world,
Vector< Bool > &  failures 
) const
virtual

Reimplemented from casacore::Coordinate.

virtual Bool casacore::DirectionCoordinate::toWorld ( Vector< Double > &  world,
const Vector< Double > &  pixel,
Bool  useConversionFrame = True 
) const
virtual

Convert a pixel position to a world position or vice versa.

Returns True if the conversion succeeds, otherwise it returns False and method errorMessage returns its error message. The output vectors are appropriately resized. if useConversionFrame, if the coordinate has a conversion layer frame, it is used. Else, the native frame is used for the conversion.

Implements casacore::Coordinate.

Bool casacore::DirectionCoordinate::toWorld ( MDirection world,
const Vector< Double > &  pixel 
) const

A convenient way to turn the world vector into an MDirection or MVDirection for further processing in the Measures system.


We could improve the performance of this if it would be useful. However it is expected that normally one would just call this once to get a template MDirection, and then call the vector versions.
In case of a failure, the versions with a Bool return value will return False. The other versions will throw an exception.

Bool casacore::DirectionCoordinate::toWorld ( MVDirection world,
const Vector< Double > &  pixel 
) const
MVDirection casacore::DirectionCoordinate::toWorld ( const Vector< Double > &  pixel) const
virtual Bool casacore::DirectionCoordinate::toWorldMany ( Matrix< Double > &  world,
const Matrix< Double > &  pixel,
Vector< Bool > &  failures 
) const
virtual

Batch up a lot of transformations.

The first (most rapidly varying) axis of the matrices contain the coordinates. Returns False if any conversion failed and errorMessage() will hold a message. The failures array is the length of the number of conversions (True for failure, False for success)

Reimplemented from casacore::Coordinate.

virtual Coordinate::Type casacore::DirectionCoordinate::type ( ) const
virtual
virtual Vector<String> casacore::DirectionCoordinate::worldAxisNames ( ) const
virtual

Return the requested attributed.

Implements casacore::Coordinate.

virtual Vector<String> casacore::DirectionCoordinate::worldAxisUnits ( ) const
virtual

Implements casacore::Coordinate.

Member Data Documentation

MDirection::Types casacore::DirectionCoordinate::conversionType_p
private

Definition at line 618 of file DirectionCoordinate.h.

Referenced by getReferenceConversion().

Vector<String> casacore::DirectionCoordinate::names_p
private

Axis names.

Definition at line 635 of file DirectionCoordinate.h.

MDirection::Convert* casacore::DirectionCoordinate::pConversionMachineFrom_p
mutableprivate

Definition at line 647 of file DirectionCoordinate.h.

MDirection::Convert* casacore::DirectionCoordinate::pConversionMachineTo_p
mutableprivate

Conversion machines.

"To" handles type_p -> conversionType_p "From" handles conversionType_p -> type_p;

Definition at line 646 of file DirectionCoordinate.h.

Projection casacore::DirectionCoordinate::projection_p
private

Projection parameters.

Definition at line 621 of file DirectionCoordinate.h.

RotMatrix casacore::DirectionCoordinate::rot_p
private

Rotation matrix used to handle relative coordinates.

Definition at line 641 of file DirectionCoordinate.h.

Vector<Double> casacore::DirectionCoordinate::to_degrees_p
private

WCS computes in degrees - use this to convert back and forth between current DirectionCoordinate units and degrees or radians.

Definition at line 631 of file DirectionCoordinate.h.

Vector<Double> casacore::DirectionCoordinate::to_radians_p
private

Definition at line 632 of file DirectionCoordinate.h.

MDirection::Types casacore::DirectionCoordinate::type_p
private

Direction type.

Definition at line 618 of file DirectionCoordinate.h.

Vector<String> casacore::DirectionCoordinate::units_p
private

Current units.

Definition at line 638 of file DirectionCoordinate.h.

mutable ::wcsprm casacore::DirectionCoordinate::wcs_p
private

WCS structure.

This is mutable because the wcs functions that do toPixel and toWorld (which have const signature) require a non const wcs structure. so either all of these virtual functions lose their const or we use mutable...

Definition at line 627 of file DirectionCoordinate.h.


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