NvasClass

class astroquery.nvas.NvasClass[source]

Bases: astroquery.query.BaseQuery

Attributes Summary

TIMEOUT
URL
band_freqs
valid_bands

Methods Summary

extract_image_urls(html_in[, get_uvfits]) Helper function that uses regexps to extract the image urls from the given HTML.
get_image_list(coordinates[, radius, …]) Function that returns a list of urls from which to download the FITS images.
get_images(coordinates[, radius, max_rms, …]) Get an image around a target/ coordinates from the NVAS image archive.
get_images_async(coordinates[, radius, …]) Serves the same purpose as get_images but returns a list of file handlers to remote files.

Attributes Documentation

TIMEOUT = 60
URL = 'https://webtest.aoc.nrao.edu/cgi-bin/lsjouwer/archive-pos.pl'
band_freqs = {'C': (4, 8), 'D': (110, 170), 'E': (60, 90), 'F': (90, 140), 'K': (18, 26.5), 'Ka': (26.5, 40), 'L': (1, 2), 'Q': (30, 50), 'S': (2, 4), 'U': (12, 18), 'V': (50, 75), 'W': (75, 110), 'X': (8, 12)}
valid_bands = ['all', 'L', 'C', 'X', 'U', 'K', 'Q']

Methods Documentation

extract_image_urls(html_in, get_uvfits=False)[source]

Helper function that uses regexps to extract the image urls from the given HTML.

Parameters:
html_in : str

source from which the urls are to be extracted.

get_uvfits : bool, optional

Gets the UVfits files instead of the IMfits files when set to True. Defaults to False.

Returns:
image_urls : list

The list of URLS extracted from the input.

get_image_list(coordinates, radius=<Quantity 0.25 arcmin>, max_rms=10000, band='all', get_uvfits=False, get_query_payload=False)[source]

Function that returns a list of urls from which to download the FITS images.

Parameters:
coordinates : str or astropy.coordinates object

The target around which to search. It may be specified as a string in which case it is resolved using online services or as the appropriate astropy.coordinates object. ICRS coordinates may also be entered as strings as specified in the astropy.coordinates module.

radius : str or Quantity object, optional

The string must be parsable by Angle. The appropriate Quantity object from astropy.units may also be used. Defaults to 0.25 arcmin.

max_rms : float, optional

Maximum allowable noise level in the image (mJy). Defaults to 10000 mJy.

band : str, optional

The band of the image to fetch. Valid bands must be from [“all”,”L”,”C”,”X”,”U”,”K”,”Q”]. Defaults to ‘all’

get_uvfits : bool, optional

Gets the UVfits files instead of the IMfits files when set to True. Defaults to False.

get_query_payload : bool, optional

if set to True then returns the dictionary sent as the HTTP request. Defaults to False.

Returns:
list of image urls
get_images(coordinates, radius=<Quantity 0.25 arcmin>, max_rms=10000, band='all', get_uvfits=False, verbose=True, get_query_payload=False, show_progress=True)[source]

Get an image around a target/ coordinates from the NVAS image archive.

Parameters:
coordinates : str or astropy.coordinates object

The target around which to search. It may be specified as a string in which case it is resolved using online services or as the appropriate astropy.coordinates object. ICRS coordinates may also be entered as strings as specified in the astropy.coordinates module.

radius : str or Quantity object, optional

The string must be parsable by Angle. The appropriate Quantity object from astropy.units may also be used. Defaults to 0.25 arcmin.

max_rms : float, optional

Maximum allowable noise level in the image (mJy). Defaults to 10000 mJy.

band : str, optional

The band of the image to fetch. Valid bands must be from [“all”,”L”,”C”,”X”,”U”,”K”,”Q”]. Defaults to ‘all’

get_uvfits : bool, optional

Gets the UVfits files instead of the IMfits files when set to True. Defaults to False.

verbose : bool, optional

When True print out additional messages. Defaults to True.

get_query_payload : bool, optional

if set to True then returns the dictionary sent as the HTTP request. Defaults to False.

Returns:
A list of `~astropy.io.fits.HDUList` objects
get_images_async(coordinates, radius=<Quantity 0.25 arcmin>, max_rms=10000, band='all', get_uvfits=False, verbose=True, get_query_payload=False, show_progress=True)[source]

Serves the same purpose as get_images but returns a list of file handlers to remote files.

Parameters:
coordinates : str or astropy.coordinates object

The target around which to search. It may be specified as a string in which case it is resolved using online services or as the appropriate astropy.coordinates object. ICRS coordinates may also be entered as strings as specified in the astropy.coordinates module.

radius : str or Quantity object, optional

The string must be parsable by Angle. The appropriate Quantity object from astropy.units may also be used. Defaults to 0.25 arcmin.

max_rms : float, optional

Maximum allowable noise level in the image (mJy). Defaults to 10000 mJy.

band : str, optional

The band of the image to fetch. Valid bands must be from [“all”,”L”,”C”,”X”,”U”,”K”,”Q”]. Defaults to ‘all’

get_uvfits : bool, optional

Gets the UVfits files instead of the IMfits files when set to True. Defaults to False.

verbose : bool, optional

When True print out additional messages. Defaults to True.

get_query_payload : bool, optional

if set to True then returns the dictionary sent as the HTTP request. Defaults to False.

Returns:
A list of context-managers that yield readable file-like objects