63 lines
1.5 KiB
Python
63 lines
1.5 KiB
Python
"""Coordinate sequence utilities
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"""
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from array import array
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class CoordinateSequence:
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"""
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Iterative access to coordinate tuples from the parent geometry's coordinate
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sequence.
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Example:
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>>> from shapely.wkt import loads
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>>> g = loads('POINT (0.0 0.0)')
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>>> list(g.coords)
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[(0.0, 0.0)]
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"""
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def __init__(self, coords):
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self._coords = coords
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def __len__(self):
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return self._coords.shape[0]
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def __iter__(self):
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for i in range(self.__len__()):
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yield tuple(self._coords[i].tolist())
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def __getitem__(self, key):
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m = self.__len__()
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if isinstance(key, int):
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if key + m < 0 or key >= m:
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raise IndexError("index out of range")
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if key < 0:
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i = m + key
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else:
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i = key
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return tuple(self._coords[i].tolist())
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elif isinstance(key, slice):
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res = []
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start, stop, stride = key.indices(m)
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for i in range(start, stop, stride):
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res.append(tuple(self._coords[i].tolist()))
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return res
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else:
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raise TypeError("key must be an index or slice")
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def __array__(self, dtype=None):
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return self._coords
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@property
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def xy(self):
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"""X and Y arrays"""
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m = self.__len__()
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x = array("d")
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y = array("d")
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for i in range(m):
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xy = self._coords[i].tolist()
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x.append(xy[0])
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y.append(xy[1])
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return x, y
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