...
Access to
...
modern OpSim runs
CatSim catalogs rely on instantiations of the ObservationMetaData class to characterize telescope pointings and observing conditions. Often, users will want to base those conditions on simulated observations produced by OpSim. OpSim runs can be directly turned into ObservationMetaData instantiations using the ObservationMetaDataGenerator class defined in
Code Block |
---|
sims_catUtils/python/lsst/sims/catUtils/utils/ObservationMetaDataGenerator.py |
The ObservationMetaDataGenerator class connects to an OpSim database and then, through the method getObservationMetaData(), allows users to request ObservationMetaData instantiations that fit certain criteria (i.e. RA, Dec, airmass, seeing, etc. within a certain range).
Examples of the use of this class can be found in the CatSimTutorial_SimulationsAHM_1503.ipynb iPython notebook in the UWSST LSST-Tutorials github repository.
The ObservationMetaDataGenerator can be directly accessed using
Code Block |
---|
from lsst.sims.catUtils.utils import ObservationMetaDataGenerator
help(ObservationMetaDataGenerator) |
Note: users wishing to instantiate their own ObservationMetaData objects by hand can find the class defined in
Code Block |
---|
sims_catalogs_generation/python/lsst/sims/catalogs/generation/db/ObservationMetaData.py |
which can be accessed by
Code Block |
---|
from lsst.sims.catalogs.generation.db import ObservationMetaData
help(ObservationMetaData) |
Access to Deprecated OpSim runs
Version 3.61 of the OpSim output is stored in the LSST database and can be queried using the class OpSim3_61DBObject whose source code can be found in /sims_catUtils/python/lsst/sims/catUtils/baseCatalogModels/OpSim3_61DBObject.py. Pointings are stored based on their RA, Dec, MJD, and the OpSim-specific obshistid. ObservationMetaData (suitable for input into InstanceCatalog) can be generated from an obshistid using the class method OpSim3_61DBObject.getObservationMetaData(). We will begin by discussing how to search OpSim for desired pointings (and their obshistid values). We will then show how to convert the pointings into ObservationMetaData instantiations.
...