Changeset 493

Timestamp:

02/21/05 18:05:23 (20 years ago)

Author:

kil064

Message:

function stokesLength() -> nStokes()

getStokesSpectrumLabel and getCircularSpectrumLabel combined into

getPolarizationLabel

getCircularSpectrum -> stokesToPolSpectrum

This is a more consistent set. Move some functionality to SDPolUtil

Location:

trunk/src

Files:

• SDMemTable.cc (modified) (3 diffs)
• SDMemTable.h (modified) (2 diffs)

trunk/src/SDMemTable.cc

@@ -371 +371 @@
 
 
-int SDMemTable::stokesLength() const
+int SDMemTable::nStokes() const
 {
    return stokesCol_.shape(0).nelements();        // All rows same shape
@@ -428 +428 @@
 }
 
-std::string SDMemTable::getStokesSpectrumLabel (Bool doPol) const
+std::string SDMemTable::getPolarizationLabel (Bool linear, Bool stokes, Bool linPol, Int polIdx) const
+{
+   uInt idx = polSel_;   
+   if (polIdx >=0) idx = polIdx;
 //
-// Gets STokes label depending on cursor polSel location
-//  doPol=False  : I,Q,U,V
-//  doPol=True   : I,P,PA,V   ; P = sqrt(Q**2+U**2), PA = 0.5*atan2(Q,U)
+   return SDPolUtil::polarizationLabel (idx, linear, stokes, linPol);
+}
+
+
+
+std::vector<float> SDMemTable::stokesToPolSpectrum (Int whichRow, Bool toLinear, uInt polIdx) const
 //
+// polIdx
+//   0:3 -> RR,LL,Real(RL),Imag(RL)
+//          XX,YY,Real(XY),Image(XY)
+//
+// Gets only
+//  RR = I + V
+//  LL = I - V
+// at the moment
+//
 {
   AlwaysAssert(asap::nAxes==4,AipsError);
-  if (nPol()!=1 && nPol()!=2 && nPol()!=4) {
-     throw (AipsError("You must have 1,2 or 4 polarizations to get the Stokes parameters"));
+  if (nStokes()!=4) {
+     throw (AipsError("You must have 4 Stokes to convert to linear or circular"));
   }
 //
-   Stokes::StokesTypes type = Stokes::Undefined;
-   switch (polSel_) {
-      case 0:
-        {
-           type = Stokes::I;
-        }
-        break;
-      case 1:
-        {
-           if (doPol) {
-              type = Stokes::Plinear;
-           } else {
-              type = Stokes::Q;
-           }
-        }
-      case 2:
-        {
-           if (doPol) {
-              type = Stokes::Pangle;
-           } else {
-              type = Stokes::U;
-           }
-        }
-        break;
-      case 3:
-        {
-           type = Stokes::V;
-        }
-        break;
-      default:
-        {
-            throw(AipsError("Unknown Stokes type"));
-        }
-   }
-//
-   return SDPolUtil::stokesString(type);
-}
-
-
-
-std::vector<float> SDMemTable::getCircularSpectrum(Int whichRow, 
-                                                   Bool doRR) const 
-  // Gets
-  //  RR = I + V
-  //  LL = I - V
-{
-  AlwaysAssert(asap::nAxes==4,AipsError);
-  if (nPol()!=4) {
-     throw (AipsError("You must have 4 polarizations to get RR or LL"));
-  }
-  Array<Float> arr;
+  Array<Float> arr, out;
   stokesCol_.get(whichRow, arr);
 
-  // Set current cursor location
+// Set current cursor location
 
   const IPosition& shape = arr.shape();
@@ -499 +464 @@
   getCursorSlice(start, end, shape);
 
-  // Get I and V slices
-
-  Array<Float> I = SDPolUtil::getStokesSlice(arr,start,end,"I");
-  Array<Float> V = SDPolUtil::getStokesSlice(arr,start,end,"V");
-
-  // Compute output 
-
-  Array<Float> out = SDPolUtil::circularPolarizationFromStokes(I, V, doRR);
-
-  // Copy to output
-
-  IPosition vecShape(1,shape(asap::ChanAxis));
-  Vector<Float> outV = out.reform(vecShape);
-  std::vector<float> stlout;
-  outV.tovector(stlout);
-
-  return stlout;
-}
-
-
-std::string SDMemTable::getCircularSpectrumLabel (Bool doRR) const
+// Get the slice
+
+  if (toLinear) {
+     throw(AipsError("Conversion to linears not yet supported"));
+  } else {
+     Bool doRR = (polIdx==0);
+     if(polIdx>1) {
+        throw(AipsError("Only conversion to RR & LL is currently supported"));
+     }
+
+// Get I and V slices
+
+     Array<Float> I = SDPolUtil::getStokesSlice(arr,start,end,"I");
+     Array<Float> V = SDPolUtil::getStokesSlice(arr,start,end,"V");
+
+// Compute output 
+
+     out = SDPolUtil::circularPolarizationFromStokes(I, V, doRR);
+   }
+
+// Copy to output
+
+   IPosition vecShape(1,shape(asap::ChanAxis));
+   Vector<Float> outV = out.reform(vecShape);
+   std::vector<float> stlout;
+   outV.tovector(stlout);
 //
-// Gets Circular label 
-//
-{
-   Stokes::StokesTypes type = Stokes::Undefined;
-   if (doRR) {
-      type = Stokes::RR;
-   } else {
-      type = Stokes::LL;
-   }
-//
-   return SDPolUtil::stokesString(type);
-}
-
-
+   return stlout;
+}
 
 

trunk/src/SDMemTable.h

@@ -94 +94 @@
   virtual std::vector<bool> getMask(casa::Int whichRow=0) const;
 
-  // When we can handle input correlations being either circular or
-  // linear, we should probably have functions; getLinear,
-  // getCircular, getStokes since one can inter-convert between all
-  // three regardless of the input provided there are 4
-  // polarizations. For now, we are assuming, if there are 4
-  // polarizations, that we have linears.  getSpectrum is then
-  // 'getLinear', getStokesSpectrum is 'getStokes' and
-  // getCircularSpectrum is 'getCircular'
-
   // Get length of STokes spectrum. XX & YY -> I
   // Anything else the length stays the same.
-  int stokesLength() const;
+  int nStokes() const;
 
   // Get specific Stokes at cursor location. One of either I,Q,U,V or I,P,PA,V (doPol=True)
@@ -114 +105 @@
                                                casa::Float paOffset=0.0) const;
 
-  // Returns String for selected Stokes (polSel_)
-  std::string getStokesSpectrumLabel (casa::Bool doPol) const;
-
-  // Get RR or LL at cursor location (except not polSel_)
-  virtual std::vector<float> getCircularSpectrum(casa::Int whichRow=0, 
-                                                 casa::Bool rr=casa::True) const;
-
-  // Get circular label
-  std::string getCircularSpectrumLabel (casa::Bool rr=casa::True) const;
+  // Returns Label for polarization selected by polSel_ (or over-ridden
+  // with arg. polIdx).  If doStokes is False,
+  // returns label for raw correlations (linear or circular). If True returns label for
+  // Stokes.  If doPol=False, I,Q,U,V else I,P,PA,V
+  std::string getPolarizationLabel (casa::Bool linear, casa::Bool stokes, 
+                                    casa::Bool linPol, casa::Int polIdx=-1) const;
+
+  // Convert Stokes to linear or circular polarizations (specified by polIdx=0:3).
+  // Presently, only conversion to RR or LL is supported.
+  virtual std::vector<float> stokesToPolSpectrum (casa::Int whichRow, casa::Bool toLinear,
+                                                  casa::uInt polIdx) const;
 
   // Get all Stokes at the specified Beam/IF cursor location (ignoring