produce_mock_data#

cygrid.produce_mock_data(mapcenter, mapsize, beamsize_fwhm, num_samples, num_sources)[source]#

Produce mock raw data (including coordinate pairs) for testing.

The raw data mimics a continuum observation (i.e., one flux density value per position) containing only Gaussian noise and some point sources.

Parameters:

mapcentertuple of floats: Center coordinates, (lon, lat) of the generated (rectangular) map [deg].
mapsizetuple of floats: Size of map, (width, height) of the generated map [deg].
beamsize_fwhmfloat: FWHM beam size [deg]. The artificial point sources, which are sampled, will be convolved with this.
num_samplesint: Number of samples to produce. Note that this must be large enough to ensure full sampling of the map (otherwise artifacts will appear, which are caused by so-called aliasing).
num_sourcesint: Number of artificial point sources to be placed into the map.

Returns:

lonsarray of float64 [1D]: Longitude coordinates for each sample.
latsarray of float64 [1D]: Latitude coordinates for each sample.
signalarray of float64 [1D]: The artifical raw data signal for each position.

Notes

As in real astronomical measurements, the point sources are convolved with the instrument’s response function (PSF), or telescope beam. The longitude map size is scaled with \(\cos b\), where \(b\) is the latitude. This is to ensure that the true-angular size roughly matches the given map width.