The Sector class

The Sector class is used to manage imaging parameters for an image.

class rapthor.lib.sector.Sector(name, ra, dec, width_ra, width_dec, field)

The Sector object contains various parameters for a sector of the field. Sectors are used only in image and predict operations

Parameters:
namestr

Name of sector

rafloat

RA in degrees of sector center

decfloat

Dec in degrees of sector center

width_rafloat

Width of sector in RA degrees

width_decfloat

Width of sector in Dec in degrees

fieldField object

Field object

filter_skymodel(skymodel)

Filters input skymodel to select only sources that lie inside the sector

Parameters:
skymodelLSMTool skymodel object

Input sky model

Returns:
filtered_skymodelLSMTool skymodel object

Filtered sky model

get_distance_to_obs_center()

Return the overall minimum and maximum distance in degrees from any sector vertex (and sector center) to the phase center of the observation

Returns:
min_dist, max_distfloat, float

Minimum and maximum distance in degrees

get_nwavelengths(cellsize_deg, timestep_sec)

Returns nwavelengths for WSClean BL-based averaging

The value depends on the integration time given the specified maximum allowed smearing. We scale it from the imaging cell size assuming normal sampling as:

max baseline in nwavelengths = 1 / theta_rad ~= 1 / (cellsize_deg * 3 * pi / 180) nwavelengths = max baseline in nwavelengths * 2 * pi * integration time in seconds / (24 * 60 * 60) / 4

Parameters:
cellsize_degfloat

Pixel size of image in degrees

timestep_secfloat

Length of one timestep in seconds

get_obs_parameters(parameter)

Returns list of parameters for all observations

Parameters:
parameterstr

Name of parameter to return

Returns:
parameterslist

List of parameters, with one entry for each observation

get_vertices_radec()

Return the vertices as RA, Dec for the sector boundary

intialize_vertices()

Determines the vertices of the sector polygon

make_region_file(outputfile, region_format='ds9')

Make a ds9 or CASA region file for the sector boundary

Parameters:
outputfilestr

Name of output region file

region_formatstr, optional

Format of region file: ‘ds9’ or ‘casa’

make_skymodel(index)

Makes predict sky model

Parameters:
indexint

Iteration index

make_vertices_file()

Make a vertices file for the sector boundary

set_imaging_parameters(do_multiscale=False, recalculate_imsize=False)

Sets the parameters needed for the imaging operation

Parameters:
do_multiscalebool, optional

If True, multiscale clean is done

recalculate_imsizebool, optional

If True, the image size is recalculated based on the current sector region

set_prediction_parameters()

Sets the predict parameters