Add calib_astrometryUsed flag to AstrometryTask

Previous merge was accidental.  The actual changes are here.
Includes a quick test which only shows that the task is able
to write to the schema and sources table.

python/lsst/meas/astrom/astrometry.py

@@ -25,8 +25,6 @@
 
 from builtins import range
 
-import random
-
 import lsst.pex.config as pexConfig
 import lsst.pipe.base as pipeBase
 import lsst.afw.geom as afwGeom
@@ -61,11 +59,6 @@ class AstrometryConfig(RefMatchConfig):
         default=0.001,
         min=0,
     )
-    doWriteOutput = pexConfig.Field(
-        dtype=bool,
-        default=True,
-        doc="Write used flag to the schema",
-    )
 
 # The following block adds links to this task from the Task Documentation page.
 ## \addtogroup LSST_task_documentation
@@ -159,9 +152,9 @@ def __init__(self, refObjLoader, schema=None, **kwargs):
         """
         RefMatchTask.__init__(self, refObjLoader, schema=schema, **kwargs)
 
-        if self.config.doWriteOutput and not schema is None:
+        if schema is not None:
             self.usedKey = schema.addField("calib_astrometryUsed", type="Flag",
-                                               doc="set if source was used in astrometric calibration")
+                                           doc="set if source was used in astrometric calibration")
         else:
             self.usedKey = None
 

tests/testAstrometryTask.py

@@ -85,6 +85,46 @@ def testRadial(self):
         """
         self.doTest(afwGeom.RadialXYTransform([0, 1.01, 1e-7]))
 
+    def testUsedFlag(self):
+        """Test that the solver will record number of sources used to table
+           if it is passed a schema on initialization.
+        """
+        distortedWcs = afwImage.DistortedTanWcs(self.tanWcs, afwGeom.IdentityXYTransform())
+        self.exposure.setWcs(distortedWcs)
+        loadRes = self.refObjLoader.loadPixelBox(bbox=self.bbox, wcs=distortedWcs, filterName="r")
+        refCat = loadRes.refCat
+        refCentroidKey = afwTable.Point2DKey(refCat.schema["centroid"])
+        refFluxRKey = refCat.schema["r_flux"].asKey()
+
+        sourceSchema = afwTable.SourceTable.makeMinimalSchema()
+        measBase.SingleFrameMeasurementTask(schema=sourceSchema)  # expand the schema
+        config = AstrometryTask.ConfigClass()
+        config.wcsFitter.order = 2
+        config.wcsFitter.numRejIter = 0
+        # schema must be passed to the solver task constructor
+        solver = AstrometryTask(config=config, refObjLoader=self.refObjLoader, schema=sourceSchema)
+        sourceCat = afwTable.SourceCatalog(sourceSchema)
+        sourceCentroidKey = afwTable.Point2DKey(sourceSchema["slot_Centroid"])
+        sourceFluxKey = sourceSchema["slot_ApFlux_flux"].asKey()
+        sourceFluxSigmaKey = sourceSchema["slot_ApFlux_fluxSigma"].asKey()
+
+        for refObj in refCat:
+            src = sourceCat.addNew()
+            src.set(sourceCentroidKey, refObj.get(refCentroidKey))
+            src.set(sourceFluxKey, refObj.get(refFluxRKey))
+            src.set(sourceFluxSigmaKey, refObj.get(refFluxRKey)/100)
+
+        results = solver.run(
+            sourceCat=sourceCat,
+            exposure=self.exposure,
+        )
+        # check that the used flag is set the right number of times
+        count = 0
+        for source in sourceCat:
+            if source.get('calib_astrometryUsed'):
+                count += 1
+        self.assertEqual(count, len(results.matches))
+
     def doTest(self, pixelsToTanPixels, order=3):
         """Test using pixelsToTanPixels to distort the source positions
         """