Changeset 39685 for branches/czw_branch/20160809/psModules/src/astrom/pmAstrometryObjects.c

Timestamp:

Sep 11, 2016, 2:29:33 PM (10 years ago)

Author:

eugene

Message:

add photometry difference weighting for the astrometric fit to the psastro.config recipe; add ZPN projection to the WCS I/O

File:

• branches/czw_branch/20160809/psModules/src/astrom/pmAstrometryObjects.c (modified) (7 diffs)

branches/czw_branch/20160809/psModules/src/astrom/pmAstrometryObjects.c

@@ -225 +225 @@
     psArray *ref,
     psArray *match,
-    psStats *stats)
+    psStats *stats,
+    const psMetadata *config)
 {
     PS_ASSERT_PTR_NON_NULL(map, NULL);
@@ -232 +233 @@
     PS_ASSERT_PTR_NON_NULL(match, NULL);
     PS_ASSERT_PTR_NON_NULL(stats, NULL);
+    PS_ASSERT_PTR_NON_NULL(config, NULL);
+
+    // sigma of gaussian window to down-weight photometric outliers (ignored if NAN or 0.0)
+    bool status;
+    double photomWindowSigma  = psMetadataLookupF32 (&status, config, "PSASTRO.PHOTOM.WINDOW.SIGMA");
+    bool   photomWindowApply  = !(isnan(photomWindowSigma) || (fabs(photomWindowSigma < 0.01)));
+    double photomWindowFactor = photomWindowApply ? -0.5/PS_SQR(photomWindowSigma) : 0.0;
 
     // reassign values for clip fit
@@ -252 +260 @@
         y->data.F32[i] = refStar->FP->y;
 
-        wt->data.F32[i] = 1.01 - exp(-10.0*PS_SQR(refStar->magCal - rawStar->magCal)); // sigma = 0.22 mag
+        // wt is used as an error (sqrt(variance)) in the fit. the 1.01 prevents the weight from going to 0.0 for perfect matches
+        wt->data.F32[i] = 1.01 - exp(photomWindowFactor*PS_SQR(refStar->magCal - rawStar->magCal)); 
     }
 
@@ -776 +785 @@
     double gridOffset = psMetadataLookupF32 (&status, config, "PSASTRO.GRID.OFFSET");
 
-    // sampling scale of the grid
-    double gridScale  = psMetadataLookupF32 (&status, config, "PSASTRO.GRID.SCALE");
+     // sampling scale of the grid
+     double gridScale  = psMetadataLookupF32 (&status, config, "PSASTRO.GRID.SCALE");
+
+    // sigma of gaussian window to down-weight photometric outliers (ignored if NAN or 0.0)
+    double photomWindowSigma  = psMetadataLookupF32 (&status, config, "PSASTRO.PHOTOM.WINDOW.SIGMA");
+    bool   photomWindowApply  = !(isnan(photomWindowSigma) || (fabs(photomWindowSigma < 0.01)));
+    double photomWindowFactor = photomWindowApply ? -0.5/PS_SQR(photomWindowSigma) : 0.0;
 
     // set the static scaling factors
@@ -818 +832 @@
             }
 
-            int Npts = 10 * exp(-10.0*PS_SQR(ob1->magCal - ob2->magCal));  // sigma = 0.22 mag
+            // XXX should I make the scale factor in front a recipe value?
+            int Npts = 10 * exp(photomWindowFactor*PS_SQR(ob1->magCal - ob2->magCal)); 
 
             // accumulate bin stats
@@ -1057 +1072 @@
     double tweakNsigma = psMetadataLookupF32 (&status, recipe, "PSASTRO.TWEAK.NSIGMA");
 
+    // sigma of gaussian window to down-weight photometric outliers (ignored if NAN or 0.0)
+    double photomWindowSigma  = psMetadataLookupF32 (&status, recipe, "PSASTRO.PHOTOM.WINDOW.SIGMA");
+    bool   photomWindowApply  = !(isnan(photomWindowSigma) || (fabs(photomWindowSigma < 0.01)));
+    double photomWindowFactor = photomWindowApply ? -0.5/PS_SQR(photomWindowSigma) : 0.0;
+
     nBin = 2*tweakRange / tweakScale;
     psVector *xHist = psVectorAlloc (nBin, PS_TYPE_F32);
@@ -1083 +1103 @@
                 continue;
 
-            int Npts = 10 * exp(-10.0*PS_SQR(ob1->magCal - ob2->magCal));  // sigma = 0.22 mag
+            // XXX should I make the scale factor in front a recipe value?
+            int Npts = 10 * exp(photomWindowFactor*PS_SQR(ob1->magCal - ob2->magCal));  // sigma = 0.22 mag
 
             xHist->data.F32[xBin] += Npts;