FgcmFitCycleTask#

FgcmFitCycleTask is the task to run the fgcm fit from star observations generated from FgcmBuildFromIsolatedStarsTask or lsst.fgcmcal.fgcmBuildStars.FgcmBuildStarsTask using the look-up table generated from FgcmMakeLutTask. This code can either be run one “fit cycle” at a time (useful for development/testing) or all together (if config.doMultipleCycles = True. The final “fit cycle” is a cleanup that does not fit atmosphere or model parameters, but instead generates the final tables required for input to FgcmOutputProductsTask.

This task will produce a large number of QA plots which will be put into the butler with names following the template fgcm_Cycle{N}_{Name}_Plot. This template makes it easy to see all the plots from a single fit cycle sorted together. By default, only QA plots from the final two fit cycles (the next-to-last cycle is a full fit and the last cycle is the post-fit cleanup) will be output, unless config.doPlotsBeforeFinalCycles = True.

The plots can either be accessed via a dedicated interface to butler plots, or they may be downloaded to the current directory with the following butler command:

butler retrieve-artifacts REPO ./ --collections COLLECTION -d "fgcm_CycleN_*_Plot" --no-preserve-path

This is the third task in a typical fgcmcal processing chain. The first is FgcmMakeLutTask, the second is FgcmBuildFromIsolatedStarsTask, and the fourth is FgcmOutputProductsTask.

Processing summary#

FgcmFitCycleTask reads in the star observations and the look-up table, performs an atmosphere and instrument fit, and outputs fit parameters as well as a comprehensive list of QA plots. If the config option config.isFinalCycle = True then additional datafiles are output that are used by FgcmOutputProductsTask. This is set automatically when config.doMultipleCycles = True.

In single-cycle mode, FgcmFitCycleTask will output a new config file in the current working directory with recommended settings for the subsequent fit cycle.

Python API summary#

Retargetable subtasks#

Configuration fields#