Merge pull request #217 from lsst/tickets/DM-41642

DM-41642: Fix crashes when FLUX keyword is not set in header.

python/lsst/cp/pipe/ptc/cpExtractPtcTask.py

@@ -312,10 +312,14 @@ def runQuantum(self, butlerQC, inputRefs, outputRefs):
         # containing flat exposures and their IDs.
         matchType = self.config.matchExposuresType
         if matchType == 'TIME':
-            inputs['inputExp'] = arrangeFlatsByExpTime(inputs['inputExp'], inputs['inputDims'])
+            inputs['inputExp'] = arrangeFlatsByExpTime(inputs['inputExp'], inputs['inputDims'], log=self.log)
         elif matchType == 'FLUX':
-            inputs['inputExp'] = arrangeFlatsByExpFlux(inputs['inputExp'], inputs['inputDims'],
-                                                       self.config.matchExposuresByFluxKeyword)
+            inputs['inputExp'] = arrangeFlatsByExpFlux(
+                inputs['inputExp'],
+                inputs['inputDims'],
+                self.config.matchExposuresByFluxKeyword,
+                log=self.log,
+            )
         else:
             inputs['inputExp'] = arrangeFlatsByExpId(inputs['inputExp'], inputs['inputDims'])
 
@@ -469,7 +473,11 @@ def run(self, inputExp, inputDims, taskMetadata, inputPhotodiodeData=None):
         # 'expTime' can stand for exposure time, flux, or ID.
         for expTime in inputExp:
             exposures = inputExp[expTime]
-            if len(exposures) == 1:
+            if not np.isfinite(expTime):
+                self.log.warning("Illegal/missing %s found (%s). Dropping exposure %d",
+                                 self.config.matchExposuresType, expTime, exposures[0][1])
+                continue
+            elif len(exposures) == 1:
                 self.log.warning("Only one exposure found at %s %f. Dropping exposure %d.",
                                  self.config.matchExposuresType, expTime, exposures[0][1])
                 continue

python/lsst/cp/pipe/utils.py

@@ -448,7 +448,7 @@ def funcAstier(pars, x):
     return 0.5/(a00*gain*gain)*(np.exp(2*a00*x*gain)-1) + noise/(gain*gain)  # C_00
 
 
-def arrangeFlatsByExpTime(exposureList, exposureIdList):
+def arrangeFlatsByExpTime(exposureList, exposureIdList, log=None):
     """Arrange exposures by exposure time.
 
     Parameters
@@ -457,6 +457,8 @@ def arrangeFlatsByExpTime(exposureList, exposureIdList):
         Input list of exposure references.
     exposureIdList : `list` [`int`]
         List of exposure ids as obtained by dataId[`exposure`].
+    log : `lsst.utils.logging.LsstLogAdapter`, optional
+        Log object.
 
     Returns
     ------
@@ -470,13 +472,15 @@ def arrangeFlatsByExpTime(exposureList, exposureIdList):
     assert len(exposureList) == len(exposureIdList), "Different lengths for exp. list and exp. ID lists"
     for expRef, expId in zip(exposureList, exposureIdList):
         expTime = expRef.get(component='visitInfo').exposureTime
+        if not np.isfinite(expTime) and log is not None:
+            log.warning("Exposure %d has non-finite exposure time.", expId)
         listAtExpTime = flatsAtExpTime.setdefault(expTime, [])
         listAtExpTime.append((expRef, expId))
 
     return flatsAtExpTime
 
 
-def arrangeFlatsByExpFlux(exposureList, exposureIdList, fluxKeyword):
+def arrangeFlatsByExpFlux(exposureList, exposureIdList, fluxKeyword, log=None):
     """Arrange exposures by exposure flux.
 
     Parameters
@@ -487,6 +491,8 @@ def arrangeFlatsByExpFlux(exposureList, exposureIdList, fluxKeyword):
         List of exposure ids as obtained by dataId[`exposure`].
     fluxKeyword : `str`
         Header keyword that contains the flux per exposure.
+    log : `lsst.utils.logging.LsstLogAdapter`, optional
+        Log object.
 
     Returns
     -------
@@ -500,7 +506,16 @@ def arrangeFlatsByExpFlux(exposureList, exposureIdList, fluxKeyword):
     assert len(exposureList) == len(exposureIdList), "Different lengths for exp. list and exp. ID lists"
     for expRef, expId in zip(exposureList, exposureIdList):
         # Get flux from header, assuming it is in the metadata.
-        expFlux = expRef.get().getMetadata()[fluxKeyword]
+        try:
+            expFlux = expRef.get().getMetadata()[fluxKeyword]
+        except KeyError:
+            # If it's missing from the header, continue; it will
+            # be caught and rejected when pairing exposures.
+            expFlux = None
+        if expFlux is None:
+            if log is not None:
+                log.warning("Exposure %d does not have valid header keyword %s.", expId, fluxKeyword)
+            expFlux = np.nan
         listAtExpFlux = flatsAtExpFlux.setdefault(expFlux, [])
         listAtExpFlux.append((expRef, expId))