如何从两个点数组创建Shapely LineString

Question

我正在尝试把两个数组合并成一个单一的LineString对象。我试过很多种方法，但总是遇到这个错误：

>>> array = [(0,0),(1,0),(2,0),(3,0)][(1,3),(1.4,2),(2,0)]

TypeError: list indices must be integers, not tuple

##      A
##       \
##        \
##         X
##          \
##           \
## B-----C-----D-----F

## Test to Identify Junctions - Shared points where two or more lines intersect

def test_find_junctions(self):
    g = PreserveTopology()
    # LINE BCDF, AXD
    array = [(0,0),(1,0),(2,0),(3,0)][(1,3),(1.4,2),(2,0)]
    # LINE AXD
    #array2 = [(1,3),(1.4,2),(2,0)]
    array_as_linestring = LineString(array)
    #array2_as_linestring = LineString(array2)
    result = g.find_junctions_line(array_as_linestring)
    assert_equal(result,(2,0))

Answer 1

看起来你有两条线段，所以你需要准备一个包含线段的列表，或者使用一个叫做多线段的结构。接着按照@David的建议来修复语法错误，你可以构建这两种结构中的任意一种：

from shapely.geometry import LineString, MultiLineString
from shapely.ops import cascaded_union

array = [[(0, 0), (1, 0), (2, 0), (3, 0)], [(1, 3), (1.4, 2), (2, 0)]]

ls = [LineString(ar) for ar in array]
mls = MultiLineString(array)

Answer 2

如果你想把你的列表变成一个数组，必须把它放在方括号里，然后用逗号把每个列表项分开。

array = [[(0,0),(1,0),(2,0),(3,0)],[(1,3),(1.4,2),(2,0)]]