How do I make a patchRef?

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#1

makeWarpTask.runDataRef wants a patchRef. I have the tract, patch, band information. But how do I make the required patchRef object?

dataId = {'tract': 4431, 'patch': 17, 'band': 'i'}

I’m running under w_2022_32 using the DP0.2 dataset on the RSP.

How do I coadd specifically selected calexps in a Jupyter notebook
#2

Hi @mwv, could I see more the executable statement you used, and the error message? In running a pipeline task my first thought is perhaps the skymap wasn’t passed along with tract, patch, and band.

#3

Gen2 support was completely removed in w.2022.31 so your code will not run at all in weekly 32…

#4

Just noticed this part of your message. runDataRef is a Gen2 API, hence my comment above, but of course if you are using DP0.2 on RSP that is a Gen3 butler. The gen3 equivalent of runDataRef is runQuantum but setting up the parameters to call runQuantum is non-trivial (you need to populate a dict with all the DatasetRef information). You can therefore either get the datasets you want separately from butler and call .run()or else go a bit higher level and call lsst.ctrl.mpexec.SimplePipelineExecutor, which is a simple frontend to pipetask command line.

#5

Thanks, both.

Yeah, I was really struggling to figure out how to structure the call to runQuantum.

#6

I’ve posted a Notebook example in How do I coadd specifically selected calexps in a Jupyter notebook

along with the larger thing I’m trying to do: make coadds for templates.

#7

FWIW, I think

patch_ref = butler.registry.findDataset(datasetType="skyMap", dataId=dataId)

is one incorrect answer to my question. It generates a datasetRef to the patch.

But as @timj points out, that doesn’t generate the actual patchRef object that the Gen2 runDataRef call was expecting.

#8

I responded in the new thread you started, and I think the draft notebook I sent you via direct message, which demos use of the SimplePipelineExecutor but is not yet ready as a production-level tutorial, will be what you need here.

So I’ll mark this topic as resolved, and we’ll continue in the new thread.

#9

Yes. patchRef is a gen2 butler reference to a dataset, equivalent, but not the same as, a gen3 DeferredDatasetHandle.