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mtazzari / galario

Gpu Accelerated Library for Analysing Radio Interferometer Observations
https://mtazzari.github.io/galario/
GNU Lesser General Public License v3.0
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Coordinate mesh grid #165

Open lucadimascolo opened 5 years ago

lucadimascolo commented 5 years ago

Quick question. get_coords_meshgrid computes the angular distances between all the points on a given grid and its centre. Since these are angular separations and assuming a small-angle approximation, shouldn't the expression for the distance along the R.A. direction,

x = (np.linspace(0.5, -0.5 + 1./float(ncol), ncol, dtype=real_dtype)) * ncol * dxy

include a corrective cos(Dec0), with Dec0 given by the declination of the grid centre?