def makeMeasurement(self, values):
"""Compute the number of non-updated DIAObjects.
Parameters
----------
values : sequence [`dict` [`str`, `int` or `None`]]
A list where each element corresponds to a metadata object passed
to `run`. Each `dict` has the following keys:
``"updatedObjects"``
The number of DIAObjects updated for this image (`int` or
`None`). May be `None` if the image was not
successfully associated.
``"unassociatedObjects"``
The number of DIAObjects not associated with a DiaSource in
this image (`int` or `None`). May be `None` if the image was
not successfully associated.
Returns
-------
measurement : `lsst.verify.Measurement` or `None`
The total number of unassociated objects.
"""
nUpdated = 0
nUnassociated = 0
associated = False
for value in values:
if value["updatedObjects"] is not None \
and value["unassociatedObjects"] is not None:
try:
nUpdated += value["updatedObjects"]
nUnassociated += value["unassociatedObjects"]
except TypeError as e:
raise MetricComputationError(
"Corrupted value of numUpdatedDiaObjects "
"or numUnassociatedDiaObjects") from e
associated = True
if associated:
if nUpdated <= 0 and nUnassociated <= 0:
raise MetricComputationError(
"No pre-existing DIAObjects; can't compute updated fraction."
)
else:
fraction = nUpdated / (nUpdated + nUnassociated)
return Measurement(self.getOutputMetricName(self.config),
fraction * u.dimensionless_unscaled)
else:
self.log.info("Nothing to do: no association results found.")
return None