HighResolutionHipsTask

HighResolutionHipsTask is a task to warp coadd images into (HiPS)-compatible HPX exposures. Currently, the task includes a custom quantum-graph generation code, which is accessed from the command-line with build-high-resolution-hips-qg. Note that this task only generates HiPS-compatible exposures, it does not generate a HiPS directory tree.

Processing summary

In order to use this task from pipetask, you must generate a custom quantum graph. There are two stages. First one segments the survey with build-high-resolution-hips-qg segment. Second, one builds a quantum graph for a given segment with build-high-resolution-hips-qg build.

build-high-resolution-hips-qg segment -r REPO -p PIPELINE -c COLLECTIONS [COLLECTIONS] [-o HPIX_BUILD_ORDER]

The default for the build healpix order (that is, nside = 2**HPIX_BUILD_ORDER) is 1, so that the generator segments the sky over large areas. The PIPELINE is a pipeline yaml that must contain only one task (HighResolutionHipsTask) and should contain any configuration overrides. Depending on the workflow engine, one may wish to build quantum graphs over a smaller region of the sky. This will print out healpix pixels (nest ordering) over which to segment the sky. For each healpix segment one can now build a quantum graph:

build-high-resolution-hips-qg build -r REPO -p PIPELINE -c COLLECTIONS [COLLECTIONS] [-o HPIX_BUILD_ORDER] -f FILENAME -P PIXELS [PIXELS ...]

This will output a quantum graph covering PIXELS at order HPIX_BUILD_ORDER and output the graph to FILENAME. This quantum graph may now be used in a regular pipetask run.

Python API summary

from lsst.pipe.tasks.hips import HighResolutionHipsTask

classHighResolutionHipsTask(**kwargs)

Task for making high resolution HiPS images...

attributeconfig

Access configuration fields and retargetable subtasks.

methodrun(pixels, coadd_exposure_handles)

Run the HighResolutionHipsTask...

See also

See the HighResolutionHipsTask API reference for complete details.

Retargetable subtasks

No subtasks.

Configuration fields

connections

Data type

lsst.pipe.base.config.HighResolutionHipsConfigConnections

Field type

ConfigField

Configurations describing the connections of the PipelineTask to datatypes

hips_order

Default

11

Field type

int Field

HIPS image order.

saveLogOutput

Default

True

Field type

bool Field

Flag to enable/disable saving of log output for a task, enabled by default.

shift_order

Default

9

Field type

int Field

HIPS shift order (such that each tile is 2**shift_order pixels on a side)

warp

Data type

lsst.afw.math._warper.WarperConfig

Field type

ConfigField

Warper configuration