pyguymer3.geo.bufferSrc.buffer_CoordinateSequence

pyguymer3.geo.bufferSrc.buffer_CoordinateSequence(coords, dist, /, *, debug=True, eps=1e-12, fill=1.0, fillSpace='EuclideanSpace', nAng=9, nIter=100, prefix='.', ramLimit=1073741824, simp=0.1, tol=1e-10)[source]

Buffer a CoordinateSequence

This function reads in a CoordinateSequence that exists on the surface of the Earth and returns a [Multi]Polygon of the same CoordinateSequence buffered by a constant distance (in metres).

Parameters:

  • coords (shapely.coords.CoordinateSequence) – the CoordinateSequence

  • dist (float) – the Geodesic distance to buffer each point within the CoordinateSequence by (in metres)

  • debug (bool, optional) – print debug messages

  • eps (float, optional) – the tolerance of the Vincenty formula iterations

  • fill (float, optional) – the Euclidean or Geodesic distance to fill in between each point within the shapes by (in degrees or metres)

  • fillSpace (str, optional) – the geometric space to perform the filling in (either “EuclideanSpace” or “GeodesicSpace”)

  • nAng (int, optional) – the number of angles around each point within the CoordinateSequence that are calculated when buffering

  • nIter (int, optional) – the maximum number of iterations (particularly the Vincenty formula)

  • prefix (str, optional) – change the name of the output debugging CSVs

  • ramLimit (int, optional) – the maximum RAM usage of each “large” array (in bytes)

  • simp (float, optional) – how much the final [Multi]Polygons is simplified by; negative values disable simplification (in degrees)

  • tol (float, optional) – the Euclidean distance that defines two points as being the same (in degrees)

Returns:

buffs – the buffered CoordinateSequence

Return type:

shapely.geometry.polygon.Polygon, shapely.geometry.multipolygon.MultiPolygon

Notes

According to the Shapely documentation for the method object.buffer() :

“Passed a distance of 0, buffer() can sometimes be used to “clean” self-touching or self-crossing polygons such as the classic “bowtie”. Users have reported that very small distance values sometimes produce cleaner results than 0. Your mileage may vary when cleaning surfaces.”

According to the Shapely documentation for the function shapely.geometry.polygon.orient() :

“A sign of 1.0 means that the coordinates of the product’s exterior ring will be oriented counter-clockwise.”

Copyright 2017 Thomas Guymer [1]

References