hats.catalog.margin_cache.margin_catalog

Classes

MarginCatalog

A HATS Catalog used to contain the 'margin' of another HATS catalog.

Module Contents

class MarginCatalog(catalog_info: hats.catalog.dataset.table_properties.TableProperties, pixels: hats.catalog.partition_info.PartitionInfo | hats.pixel_tree.pixel_tree.PixelTree | list[hats.pixel_math.HealpixPixel], catalog_path: str | pathlib.Path | upath.UPath | None = None, moc: mocpy.MOC | None = None, schema: pyarrow.Schema | None = None, original_schema: pyarrow.Schema | None = None)

Bases: hats.catalog.healpix_dataset.healpix_dataset.HealpixDataset

A HATS Catalog used to contain the ‘margin’ of another HATS catalog.

Catalogs of this type are used alongside a primary catalog, and contains the margin points for each HEALPix pixel - any points that are within a certain distance from the HEALPix pixel boundary. This is used to ensure spatial operations such as crossmatching can be performed efficiently while maintaining accuracy.

filter_by_moc(moc: mocpy.MOC) → typing_extensions.Self

Filter the pixels in the margin catalog to only include the margin pixels that overlap with the moc

For the case of margin pixels, this includes any pixels whose margin areas may overlap with the moc. This is not always done with a high accuracy, but always includes any pixels that will overlap, and may include extra partitions that do not.

Parameters:

mocmocpy.MOC

the moc to filter by

Returns:

MarginCatalog

A new margin catalog with only the pixels that overlap or that have margin area that overlap with the moc. Note that we reset the total_rows to None, as updating would require a scan over the new pixel sizes.