casa::Stokes Class Reference [Measures_module]

Stokes parameter definitions for interface to table data. More...

#include <Stokes.h>

List of all members.

Public Types
enum	StokesTypes {   Undefined,   I,   Q,   U,   V,   RR,   RL,   LR,   LL,   XX,   XY,   YX,   YY,   RX,   RY,   LX,   LY,   XR,   XL,   YR,   YL,   PP,   PQ,   QP,   QQ,   RCircular,   LCircular,   Linear,   Ptotal,   Plinear,   PFtotal,   PFlinear,   Pangle }
	The Stokes types are defined by this enum. More...
enum	{ NumberOfTypes }
	The number of StokesTypes. More...
Static Public Member Functions
static StokesTypes	type (Int stokesNumber)
	convert Int to StokesTypes, returns Stokes::Undefined if it is an invalid type
static StokesTypes	type (const String &stokesName)
	convert String to StokesTypes, returns Stokes::Undefined if it is an unrecognized string.
static String	name (StokesTypes stokesType)
	convert StokesTypes to String, Stokes::Undefined returns "??".
static Fallible< Int >	receptor1 (StokesTypes stokesType)
	map StokesTypes to receptor number (0 or 1) for the interferometric correlation products.
static Fallible< Int >	receptor2 (StokesTypes stokesType)
static Int	FITSValue (StokesTypes which)
	These two functions map stokes type to FITS type and vice versa.
static StokesTypes	fromFITSValue (Int)

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Detailed Description

Stokes parameter definitions for interface to table data.

Review Status

Test programs:

tStokes

Synopsis

This enumerates the available Stokes types, but does not define the operations for conversion between Stokes types. This class is a wrapper for the ENUM and conversion functions.

Definition at line 51 of file Stokes.h.

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Member Enumeration Documentation

anonymous enum

The number of StokesTypes.

Warning: Update NumberOfTypes when entries are added;

Enumerator:

NumberOfTypes

The number of StokesTypes.

Definition at line 123 of file Stokes.h.

enum casa::Stokes::StokesTypes

The Stokes types are defined by this enum.

Warning: DO NOT CHANGE THE ORDER OF THESE TYPES, as the integers corresponding to the enum are required for storage in Tables; One can add to these types, but the order must be preserved; The correlation products are required to have the order indicated with values of 1,2,3,4 plus n*4;

Enumerator:

Undefined	undefined value = 0
I
Q
U
V	standard stokes parameters
RR
RL
LR
LL	circular correlation products
XX
XY
YX
YY	linear correlation products
RX
RY
LX
LY
XR
XL
YR
YL	mixed correlation products
PP
PQ
QP
QQ	general quasi-orthogonal correlation products
RCircular
LCircular
Linear	single dish polarization types
Ptotal	Polarized intensity ((Q^2+U^2+V^2)^(1/2)).
Plinear	Linearly Polarized intensity ((Q^2+U^2)^(1/2)).
PFtotal	Polarization Fraction (Ptotal/I).
PFlinear	Linear Polarization Fraction (Plinear/I).
Pangle	Linear Polarization Angle (0.5 arctan(U/Q)) (in radians).

Definition at line 66 of file Stokes.h.

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Member Function Documentation

static Int casa::Stokes::FITSValue

(

StokesTypes

which

)

[static]

These two functions map stokes type to FITS type and vice versa.

If you add a StokesType you should change these functions as well.

• I,Q,U,V <-> 1,2,3,4
• RR,LL,RL,LR <-> -1,-2,-3,-4 Note! Not the same as enum order!
• XX,YY,XY,YX <-> -5,-6,-7,-8 Note! Not the same as enum order!
• Otherwise, FITS type <-> 100 + Int(stokesType). This is not standard FITS.

static StokesTypes casa::Stokes::fromFITSValue

(

Int

)

[static]

static String casa::Stokes::name

(

StokesTypes

stokesType

)

[static]

convert StokesTypes to String, Stokes::Undefined returns "??".

static Fallible<Int> casa::Stokes::receptor1

(

StokesTypes

stokesType

)

[static]

map StokesTypes to receptor number (0 or 1) for the interferometric correlation products.

e.g. XY will give receptor1==0 receptor2==1 etc. I,Q,U,V and the single dish types will produce invalid Fallible.

static Fallible<Int> casa::Stokes::receptor2

(

StokesTypes

stokesType

)

[static]

static StokesTypes casa::Stokes::type

(

Int

stokesNumber

)

[static]

convert Int to StokesTypes, returns Stokes::Undefined if it is an invalid type

static StokesTypes casa::Stokes::type

(

const String &

stokesName

)

[static]

convert String to StokesTypes, returns Stokes::Undefined if it is an unrecognized string.

The valid strings are the same as the characters used in the enum above (i.e. "I" returns Stokes::I, "Linear" returns Stokes::Linear, etc).

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

• measures/Measures/Stokes.h