CasdaClass

class astroquery.casda.CasdaClass

Bases: QueryWithLogin

Class for accessing ASKAP data through the CSIRO ASKAP Science Data Archive (CASDA). Typical usage:

result = Casda.query_region(‘22h15m38.2s -45d50m30.5s’, radius=0.5 * u.deg)

Attributes Summary

POLL_INTERVAL
TIMEOUT
URL
USERNAME

Methods Summary

cutout(table, *[, coordinates, radius, ...])	Produce a cutout from each selected file.
download_files(urls, *[, savedir])	Download a series of files
filter_out_unreleased(table)	Return a subset of the table which only includes released (public) data.
login(*[, username, store_password, ...])	login to non-public data as a known user
query_region(*args, **kwargs)	Queries the service and returns a table object.
query_region_async(coordinates, *[, radius, ...])	Queries a region around the specified coordinates.
stage_data(table, *[, verbose])	Request access to a set of data files.

Attributes Documentation

POLL_INTERVAL = 20

TIMEOUT = 30

URL = 'https://casda.csiro.au/casda_vo_tools/sia2/query'

USERNAME = ''

Methods Documentation

cutout(table, *, coordinates=None, radius=<Quantity 1. arcmin>, height=None, width=None, band=None, channel=None, verbose=False)

Produce a cutout from each selected file. All requests for data must use authentication. If you have access to the data, the requested files will be brought online, a cutout produced from each file and a set of URLs to download the cutouts will be returned.

If a set of coordinates is provided along with either a radius or a box height and width, then CASDA will produce a spatial cutout at that location from each data file specified in the table. If a band or channel pair is provided then CASDA will produce a spectral cutout of that range from each data file. These can be combined to produce subcubes with restrictions in both spectral and spatial axes.

Parameters:

table: `astropy.table.Table`

A table describing the files to be staged, such as produced by query_region. It must include an access_url column.

coordinatesstr or astropy.coordinates, optional

coordinates around which to produce a cutout, the radius will be 1 arcmin if no radius, height or width is provided.

radiusstr or astropy.units.Quantity, optional

the radius of the cutout

heightstr or astropy.units.Quantity, optional

the height for a box cutout

widthstr or astropy.units.Quantity, optional

the width for a box cutout

bandlist of astropy.units.Quantity with two elements, optional

the spectral range to be included, may be low and high wavelengths in metres or low and high frequencies in Hertz. Use None for an open bound.

channellist of int with two elements, optional

the spectral range to be included, the low and high channels (i.e. planes of a cube) inclusive

verbose: bool, optional

Should status messages be logged periodically, defaults to False

Returns:

A list of urls of both the requested files/cutouts and the checksums for the files/cutouts

download_files(urls, *, savedir='')

Download a series of files

Parameters:

urls: list of strings

The list of URLs of the files to be downloaded.

savedir: str, optional

The directory in which to save the files.

Returns:

A list of the full filenames of the downloaded files.

filter_out_unreleased(table)

Return a subset of the table which only includes released (public) data.

Parameters:

table: `astropy.table.Table`

A table of results as returned by query_region. Must include an obs_release_date column.

Returns:

tableastropy.table.Table

The table with all unreleased (non public) data products filtered out.

login(*, username=None, store_password=False, reenter_password=False)

login to non-public data as a known user

Parameters:

usernamestr, optional

Username to the CASDA archive, uses ATNF OPAL credentials. If not given, it should be specified in the config file.

store_passwordbool, optional

Stores the password securely in your keyring. Default is False.

reenter_passwordbool, optional

Asks for the password even if it is already stored in the keyring. This is the way to overwrite an already stored passwork on the keyring. Default is False.

query_region(*args, **kwargs)

Queries the service and returns a table object.

Queries a region around the specified coordinates. Either a radius or both a height and a width must be provided.

Parameters:

coordinatesstr or astropy.coordinates.

coordinates around which to query

radiusstr or astropy.units.Quantity, optional

the radius of the cone search

heightstr or astropy.units.Quantity, optional

the height for a box region

widthstr or astropy.units.Quantity, optional

the width for a box region

get_query_payloadbool, optional

Just return the dict of HTTP request parameters.

cachebool

Defaults to True. If set overrides global caching behavior. See caching documentation.

Returns:

tableA Table object.

query_region_async(coordinates, *, radius=<Quantity 1. arcmin>, height=None, width=None, get_query_payload=False, cache=True)

Queries a region around the specified coordinates. Either a radius or both a height and a width must be provided.

Parameters:

coordinatesstr or astropy.coordinates.

coordinates around which to query

radiusstr or astropy.units.Quantity, optional

the radius of the cone search

heightstr or astropy.units.Quantity, optional

the height for a box region

widthstr or astropy.units.Quantity, optional

the width for a box region

get_query_payloadbool, optional

Just return the dict of HTTP request parameters.

cachebool

Defaults to True. If set overrides global caching behavior. See caching documentation.

Returns:

responserequests.Response

The HTTP response returned from the service. All async methods should return the raw HTTP response.

stage_data(table, *, verbose=False)

Request access to a set of data files. All requests for data must use authentication. If you have access to the data, the requested files will be brought online and a set of URLs to download the files will be returned.

Parameters:

table: `astropy.table.Table`

A table describing the files to be staged, such as produced by query_region. It must include an access_url column.

verbose: bool, optional

Should status message be logged periodically, defaults to False

Returns:

A list of urls of both the requested files/cutouts and the checksums for the files/cutouts