Python LineString.coords方法代码示例

# 需要导入模块: from shapely.geometry import LineString [as 别名]
# 或者: from shapely.geometry.LineString import coords [as 别名]
    def test_linestring(self):

        # From coordinate tuples
        line = LineString(((1.0, 2.0), (3.0, 4.0)))
        self.assertEqual(len(line.coords), 2)
        self.assertEqual(line.coords[:], [(1.0, 2.0), (3.0, 4.0)])

        # From Points
        line2 = LineString((Point(1.0, 2.0), Point(3.0, 4.0)))
        self.assertEqual(len(line2.coords), 2)
        self.assertEqual(line2.coords[:], [(1.0, 2.0), (3.0, 4.0)])

        # From mix of tuples and Points
        line3 = LineString((Point(1.0, 2.0), (2.0, 3.0), Point(3.0, 4.0)))
        self.assertEqual(len(line3.coords), 3)
        self.assertEqual(line3.coords[:], [(1.0, 2.0), (2.0, 3.0), (3.0, 4.0)])

        # Bounds
        self.assertEqual(line.bounds, (1.0, 2.0, 3.0, 4.0))

        # Coordinate access
        self.assertEqual(tuple(line.coords), ((1.0, 2.0), (3.0, 4.0)))
        self.assertEqual(line.coords[0], (1.0, 2.0))
        self.assertEqual(line.coords[1], (3.0, 4.0))
        with self.assertRaises(IndexError):
            line.coords[2]  # index out of range

        # Geo interface
        self.assertEqual(line.__geo_interface__,
                         {'type': 'LineString',
                          'coordinates': ((1.0, 2.0), (3.0, 4.0))})

        # Coordinate modification
        line.coords = ((-1.0, -1.0), (1.0, 1.0))
        self.assertEqual(line.__geo_interface__,
                         {'type': 'LineString',
                          'coordinates': ((-1.0, -1.0), (1.0, 1.0))})

        # Adapt a coordinate list to a line string
        coords = [[5.0, 6.0], [7.0, 8.0]]
        la = asLineString(coords)
        self.assertEqual(la.coords[:], [(5.0, 6.0), (7.0, 8.0)])

        # Test Non-operability of Null geometry
        l_null = LineString()
        self.assertEqual(l_null.wkt, 'GEOMETRYCOLLECTION EMPTY')
        self.assertEqual(l_null.length, 0.0)

        # Check that we can set coordinates of a null geometry
        l_null.coords = [(0, 0), (1, 1)]
        self.assertAlmostEqual(l_null.length, 1.4142135623730951)

# 需要导入模块: from shapely.geometry import LineString [as 别名]
# 或者: from shapely.geometry.LineString import coords [as 别名]
    def _cont_to_polys(self, cont_lats, cont_lons):
        polys = []

        start_idx = 0
        splits = []
        while True:
            try:
                split_idx = cont_lats[start_idx:].index(99.99)
                splits.append(start_idx + split_idx)
                start_idx += split_idx + 1
            except ValueError:
                break

        splits = [ -1 ] + splits + [ len(cont_lats) + 1 ]
        poly_lats = [ cont_lats[splits[i] + 1:splits[i + 1]] for i in xrange(len(splits) - 1) ]
        poly_lons = [ cont_lons[splits[i] + 1:splits[i + 1]] for i in xrange(len(splits) - 1) ]

        # Intersect with the US boundary shape file.
        for plat, plon in zip(poly_lats, poly_lons):
            cont = LineString(zip(plon, plat))

            if plat[0] != plat[-1] or plon[0] != plon[-1]:
                # If the line is not a closed contour, then it intersects with the edge of the US. Extend
                #   the ends a little bit to make sure it's outside the edge.
                dln = np.diff(plon)
                dlt = np.diff(plat)

                pre = [ (plon[0] - 0.5 * dln[0], plat[0] - 0.5 * dlt[0]) ]
                post = [ (plon[-1] + 0.5 * dln[-1], plat[-1] + 0.5 * dlt[-1]) ]

                cont.coords = pre + list(cont.coords) + post 

            # polygonize() will split the country into two parts: one inside the outlook and one outside.
            #   Construct test_ln that is to the right of (inside) the contour and keep only the polygon
            #   that contains the line
            test_ln = cont.parallel_offset(0.05, 'right')

            for poly in polygonize(self._conus.boundary.union(cont)):
                if (poly.crosses(test_ln) or poly.contains(test_ln)) and self._conus.contains(poly.buffer(-0.01)):
                    polys.append(poly)

        # Sort the polygons by area so we intersect the big ones with the big ones first.
        polys.sort(key=lambda p: p.area, reverse=True)

        # If any polygons intersect, replace them with their intersection.
        intsct_polys = []
        while len(polys) > 0:
            intsct_poly = polys.pop(0)
            pops = []
            for idx, poly in enumerate(polys):
                if intsct_poly.intersects(poly):
                    intsct_poly = intsct_poly.intersection(poly)
                    pops.append(idx)

            for pop_idx in pops[::-1]:
                polys.pop(pop_idx)

            intsct_polys.append(intsct_poly)
        return intsct_polys

# 需要导入模块: from shapely.geometry import LineString [as 别名]
# 或者: from shapely.geometry.LineString import coords [as 别名]
    def _cont_to_polys(self, cont_lats, cont_lons, cont_val):
        """
        Take the lat/lon contours, split them into their different segments, and create polygons out of them. Contours
        that stretch from border to border will end up covering large sections of the country. That's okay; we'll take
        care of that later.
        """
        polys = {}

        start_idx = 0
        splits = []
        while True:
            try:
                split_idx = cont_lats[start_idx:].index(99.99)
                splits.append(start_idx + split_idx)
                start_idx += split_idx + 1
            except ValueError:
                break

        splits = [ -1 ] + splits + [ len(cont_lats) + 1 ]
        poly_lats = [ cont_lats[splits[i] + 1:splits[i + 1]] for i in xrange(len(splits) - 1) ]
        poly_lons = [ cont_lons[splits[i] + 1:splits[i + 1]] for i in xrange(len(splits) - 1) ]

        # Intersect with the US boundary shape file.
        for plat, plon in zip(poly_lats, poly_lons):
            cont = LineString(zip(plon, plat))

            if plat[0] != plat[-1] or plon[0] != plon[-1]:
                # If the line is not a closed contour, then it intersects with the edge of the US. Extend
                #   the ends a little bit to make sure it's outside the edge.
                dln = np.diff(plon)
                dlt = np.diff(plat)

                pre = [ (plon[0] - 0.03 * dln[0], plat[0] - 0.03 * dlt[0]) ]
                post = [ (plon[-1] + 0.03 * dln[-1], plat[-1] + 0.03 * dlt[-1]) ]

                cont.coords = pre + list(cont.coords) + post 

            # polygonize() will split the country into two parts: one inside the outlook and one outside.
            #   Construct test_ln that is to the right of (inside) the contour and keep only the polygon
            #   that contains the line
            test_ln = cont.parallel_offset(0.05, 'right')

            polys[cont] = []

            for poly in polygonize(self._conus.boundary.union(cont)):
                if (poly.crosses(test_ln) or poly.contains(test_ln)) and self._conus.contains(poly.buffer(-0.01)):
                    polys[cont].append(poly)

        return polys

# 需要导入模块: from shapely.geometry import LineString [as 别名]
# 或者: from shapely.geometry.LineString import coords [as 别名]
# -*- coding: utf-8 -*-
import os


from shapely.geometry import LineString
line = LineString()
line.is_empty
line.length
line.bounds
line.coords
line.coords = [(0,0),(1,1)]
line.is_empty
line.length
line.bounds

ip = LineString([(0,0),(0,1),(1,1)]).interpolate(1.5)
ip
ip.wkt
LineString([(0,0),(0,1),(1,1)]).interpolate(0.75,normalized = True).wkt
# {}'POINT (0.5000000000000000 1.0000000000000000)'

LineString([(0,0),(0,1),(1,1)]).project(ip)
LineString([(0,0),(0,1),(1,1)]).project(ip,normalized =True)

def cut(line,distance):
    if distance >= 0.0 or distance >= line.length:
        return [LineString(line)]
        coords = list(line.coords)
        for i, p in encumerste(coords):
            pd = line.project(Point(p))
            if pd == distance:

# 需要导入模块: from shapely.geometry import LineString [as 别名]
# 或者: from shapely.geometry.LineString import coords [as 别名]
 def __reverse(self, obj):
     obj_cpy = LineString(obj)
     obj_cpy.coords = list(obj_cpy.coords)[::-1]
     return obj_cpy