hats.pixel_math.healpix_shim

hats.pixel_math.healpix_shim#

`is_order_valid`(→ bool)
`npix2order`(→ int)
`order2nside`(→ int)
`order2npix`(→ int)
`order2resol`(→ float)
`order2pixarea`(→ float)
`radec2pix`(→ numpy.ndarray[numpy.int64])
`ang2vec`(→ numpy.ndarray)	Converts ra and dec to cartesian coordinates on the unit sphere
`avgsize2mindist`(→ numpy.ndarray)	Get the minimum distance between pixels for a given average size
`mindist2avgsize`(→ numpy.ndarray)	Get the average size for a given minimum distance between pixels
`avgsize2order`(→ numpy.ndarray)	Get the largest order with average healpix size larger than avg_size_arcmin
`margin2order`(→ numpy.ndarray)	Get the largest order for which distance between pixels is less than margin_thr_arcmin
`order2mindist`(→ numpy.ndarray \| float)	Get the estimated minimum distance between pixels at a given order.

order2resol(order: int, *, arcmin: bool = False, unit=u.rad) → float[source]#

order2pixarea(order: int, *, degrees: bool = False, unit=u.sr) → float[source]#

radec2pix(order: int, ra: float, dec: float) → numpy.ndarray[numpy.int64][source]#

ang2vec(ra, dec, **kwargs) → numpy.ndarray[source]#: Converts ra and dec to cartesian coordinates on the unit sphere

avgsize2mindist(avg_size: numpy.ndarray) → numpy.ndarray[source]#

Get the minimum distance between pixels for a given average size

We don’t have the precise geometry of the healpix grid yet, so we are using average_size / mininimum_distance = 1.6 as a rough estimate.

Parameters:: avg_size (np.ndarray of float) – The average size of a healpix pixel
Returns:: The minimum distance between pixels for the given average size
Return type:: np.ndarray of float

mindist2avgsize(mindist: numpy.ndarray) → numpy.ndarray[source]#

Get the average size for a given minimum distance between pixels

We don’t have the precise geometry of the healpix grid yet, so we are using average_size / mininimum_distance = 1.6 as a rough estimate.

Parameters:: mindist (np.ndarray of float) – The minimum distance between pixels
Returns:: The average size of a healpix pixel for the given minimum distance between pixels.
Return type:: np.ndarray of float

avgsize2order(avg_size_arcmin: numpy.ndarray) → numpy.ndarray[source]#

Get the largest order with average healpix size larger than avg_size_arcmin

Parameters:: avg_size_arcmin (np.ndarray of float) – The average size of a healpix pixel in arcminutes
Returns:: The largest healpix order for which the average size is larger than avg_size_arcmin
Return type:: np.ndarray of int

margin2order(margin_thr_arcmin: numpy.ndarray) → numpy.ndarray[source]#

Get the largest order for which distance between pixels is less than margin_thr_arcmin

We don’t have the precise geometry of the healpix grid yet, we are using average_size / mininimum_distance = 1.6 as a rough estimate.

Parameters:: margin_thr_arcmin (np.ndarray of float) – The minimum distance between pixels in arcminutes
Returns:: The largest healpix order for which the distance between pixels is less than margin_thr_arcmin
Return type:: np.ndarray of int

order2mindist(order: numpy.ndarray | int) → numpy.ndarray | float[source]#

Get the estimated minimum distance between pixels at a given order.

We don’t have the precise geometry of the healpix grid yet, we are using average_size / mininimum_distance = 1.6 as a rough estimate.

Parameters:: order (np.ndarray of int or a single scalar int) – The healpix order
Returns:: The minimum distance between pixels in arcminutes
Return type:: np.ndarray of float or a single scalar float