healpy.query_polygon¶
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healpy.
query_polygon
(nside, vertices, inclusive=False, fact=4, nest=False, ndarray buff=None)¶ Returns the pixels whose centers lie within the convex polygon defined by the vertices array (if inclusive is False), or which overlap with this polygon (if inclusive is True).
Parameters: - nside : int
The nside of the Healpix map.
- vertices : float, array-like
Vertex array containing the vertices of the polygon, shape (N, 3).
- inclusive : bool, optional
If False, return the exact set of pixels whose pixel centers lie within the polygon; if True, return all pixels that overlap with the polygon, and maybe a few more. Default: False.
- fact : int, optional
Only used when inclusive=True. The overlapping test will be done at the resolution fact*nside. For NESTED ordering, fact must be a power of 2, less than 2**30, else it can be any positive integer. Default: 4.
- nest: bool, optional
if True, assume NESTED pixel ordering, otherwise, RING pixel ordering
- buff: int array, optional
if provided, this numpy array is used to contain the return values and must be at least long enough to do so
Returns: - ipix : int, array
The pixels which lie within the given polygon.