44 lines
1.3 KiB
Python
44 lines
1.3 KiB
Python
"""Provides functions for finding the pole of inaccessibility for a given polygon."""
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from shapely._geometry import get_point
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from shapely.constructive import maximum_inscribed_circle
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def polylabel(polygon, tolerance=1.0):
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"""Find pole of inaccessibility for a given polygon.
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Based on Vladimir Agafonkin's https://github.com/mapbox/polylabel
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Parameters
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----------
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polygon : shapely.geometry.Polygon
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Polygon for which to find the pole of inaccessibility.
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tolerance : int or float, optional
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`tolerance` represents the highest resolution in units of the
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input geometry that will be considered for a solution. (default
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value is 1.0).
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Returns
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-------
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shapely.geometry.Point
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A point representing the pole of inaccessibility for the given input
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polygon.
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Raises
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------
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shapely.errors.TopologicalError
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If the input polygon is not a valid geometry.
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Examples
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--------
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>>> from shapely.ops import polylabel
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>>> from shapely import LineString
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>>> polygon = LineString([(0, 0), (50, 200), (100, 100), (20, 50),
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... (-100, -20), (-150, -200)]).buffer(100)
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>>> polylabel(polygon, tolerance=0.001)
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<POINT (59.733 111.33)>
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"""
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line = maximum_inscribed_circle(polygon, tolerance)
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return get_point(line, 0)
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