blocks|key|167537|text|因此，我发现诀窍是使用Polygon类方法的组合来实现这一点。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|167538|如果您需要测地线坐标，则需要将这些坐标转换回WGS84+(通过pyproj、matplotlib的basemap或其他方式)。|167539|from+shapely.geometry+import+Polygon

#Create+polygon+from+lists+of+points
x+=+[list+of+x+vals]
y+=+[list+of+y+vals]

some_poly+=+Polygon(x,y)

#+Extract+the+point+values+that+define+the+perimeter+of+the+polygon
x,+y+=+some_poly.exterior.coords.xy|code-block|syntax|javascript|167540|entityMap^0|B|7|0|V|6|12|A|1D|7|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@$9|P|A|Q|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|R|8|@$9|S|A|T|B|C]|$9|U|A|V|B|C]|$9|W|A|X|B|C]]|D|@]|E|$]]|$1|H|3|I|5|J|7|Y|8|@]|D|@]|E|$K|L]]|$1|M|3|-4|5|6|7|Z|8|@]|D|@]|E|$]]]|N|$]]

So, I discovered the trick is to use a combination of the <code>Polygon</code> class methods to achieve this. 

If you want geodesic coordinates, you then need to transform these back to WGS84 (via <code>pyproj</code>, <code>matplotlib</code>'s <code>basemap</code>, or something).

<pre><code>from shapely.geometry import Polygon

#Create polygon from lists of points
x = [list of x vals]
y = [list of y vals]

some_poly = Polygon(x,y)

# Extract the point values that define the perimeter of the polygon
x, y = some_poly.exterior.coords.xy
</code></pre>

blocks|key|166494|text|可以使用NumPy.array将形状多边形转化为NumPy数组。我发现使用NumPy数组比使用coords.xy返回的数组更有用，因为坐标是成对的，而不是在两个一维数组中。使用对您的应用程序更有用的。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|166495|import+numpy+as+np
x+=+[1,+2,+3,+4]
y+=+[9,+8,+7,+6]
polygon+=+Polygon(x,y)
points+=+np.array(polygon)

#+points+is:
[[+1+9]
+[+2+8]
+[+3+7]
+[+4+6]]|code-block|syntax|javascript|166496|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

You can convert a shapely Polygon to a NumPy array using NumPy.array. I find using NumPy arrays more useful than the arrays returned by coords.xy, since the coordinates are paired, rather than in two one-dimensional arrays. Use whichever is more useful to your application.

<pre><code>import numpy as np
x = [1, 2, 3, 4]
y = [9, 8, 7, 6]
polygon = Polygon(x,y)
points = np.array(polygon)

# points is:
[[ 1 9]
 [ 2 8]
 [ 3 7]
 [ 4 6]]
</code></pre>

blocks|key|167565|text|您可以使用shapely+mapping函数：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|167566|>>>+from+shapely.geometry+import+Polygon,+mapping
>>>+sh_polygon+=+Polygon(((0,0),+(1,1),+(0,1)))
>>>+mapping(sh_polygon)
{'type':+'Polygon',+'coordinates':+(((0.0,+0.0),+(1.0,+1.0),+(0.0,+1.0),+(0.0,+0.0)),)}|code-block|syntax|javascript|167567|entityMap^0|D|7|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@$9|N|A|O|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|P|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|Q|8|@]|D|@]|E|$]]]|L|$]]

You can use the shapely <code>mapping</code> function:


<pre><code>&gt;&gt;&gt; from shapely.geometry import Polygon, mapping
&gt;&gt;&gt; sh_polygon = Polygon(((0,0), (1,1), (0,1)))
&gt;&gt;&gt; mapping(sh_polygon)
{'type': 'Polygon', 'coordinates': (((0.0, 0.0), (1.0, 1.0), (0.0, 1.0), (0.0, 0.0)),)}
</code></pre>

blocks|key|2766449|text|更新(2017-06-09)：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|2766450|由于上一个答案似乎不再适用于最新版本的shapely，因此我建议进行这次更新。|2766451|shapely提供了Numpy数组接口(正如文档所说：http://toblerity.org/shapely/project.html+)|offset|length|2766452|因此，假设poly是一个形状优美的多边形几何体：|style|CODE|2766453|In+[2]:+type(poly)
Out[2]:+shapely.geometry.polygon.Polygon|code-block|syntax|javascript|2766454|此命令将执行到numpy数组的转换：|2766455|In+[3]:+coordinates_array+=+np.asarray(poly.exterior.coords)|2766456|提示：|BOLD|2766457|必须给出多边形的exterior.coords，因为给出直接的几何体似乎也不起作用：|2766458|In+[4]:+coordinates_array+=+np.asarray(poly)
Out[4]:+array(<shapely.geometry.polygon.Polygon+object+at+0x7f627559c510>,+dtype=object)++++|2766459|entityMap|0|LINK|mutability|MUTABLE|url|http://toblerity.org/shapely/project.html^0|0|0|R|15|0|0|5|4|0|0|0|0|0|3|0|0|0^^$0|@$1|2|3|4|5|6|7|19|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|1A|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|1B|8|@]|9|@$F|1C|G|1D|1|1E]]|A|$]]|$1|H|3|I|5|6|7|1F|8|@$F|1G|G|1H|J|K]]|9|@]|A|$]]|$1|L|3|M|5|N|7|1I|8|@]|9|@]|A|$O|P]]|$1|Q|3|R|5|6|7|1J|8|@]|9|@]|A|$]]|$1|S|3|T|5|N|7|1K|8|@]|9|@]|A|$O|P]]|$1|U|3|V|5|6|7|1L|8|@$F|1M|G|1N|J|W]]|9|@]|A|$]]|$1|X|3|Y|5|6|7|1O|8|@]|9|@]|A|$]]|$1|Z|3|10|5|N|7|1P|8|@]|9|@]|A|$O|P]]|$1|11|3|-4|5|6|7|1Q|8|@]|9|@]|A|$]]]|12|$13|$5|14|15|16|A|$17|18]]]]

<h3>Update (2017-06-09):</h3> 

As the last answer seems not to work anymore with newest version of shapely, I propose this update.

shapely provides the Numpy array interface (as the doc says: <a href="http://toblerity.org/shapely/project.html" rel="nofollow noreferrer">http://toblerity.org/shapely/project.html</a> ) 

So, let <code>poly</code> be a shapely polygon geometry:

<pre><code>In [2]: type(poly)
Out[2]: shapely.geometry.polygon.Polygon
</code></pre>

This command will do the conversion to a numpy array:

<pre><code>In [3]: coordinates_array = np.asarray(poly.exterior.coords)
</code></pre>

Hint: 
One must need to give the exterior.coords for a polygon because giving the direct geometry seems not to work either:

<pre><code>In [4]: coordinates_array = np.asarray(poly)
Out[4]: array(&lt;shapely.geometry.polygon.Polygon object at 0x7f627559c510&gt;, dtype=object) 
</code></pre>

blocks|key|167590|text|我使用了这个：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|167591|list(zip(*p.exterior.coords.xy))|code-block|syntax|javascript|167592|使用：p+=+Polygon([(0,0),(1,1),(1,0),(0,0)])创建的多边形返回：|offset|length|style|CODE|167593|[(0.0,+0.0),+(1.0,+1.0),+(1.0,+0.0),+(0.0,+0.0)]|167594|entityMap^0|0|0|3|12|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|R|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|S|8|@$I|T|J|U|K|L]]|9|@]|A|$]]|$1|M|3|N|5|D|7|V|8|@]|9|@]|A|$E|F]]|$1|O|3|-4|5|6|7|W|8|@]|9|@]|A|$]]]|P|$]]

I used this:

<pre><code>list(zip(*p.exterior.coords.xy))
</code></pre>

Polygon created with: <code>p = Polygon([(0,0),(1,1),(1,0),(0,0)])</code> returns:

<pre><code>[(0.0, 0.0), (1.0, 1.0), (1.0, 0.0), (0.0, 0.0)]
</code></pre>

blocks|key|166633|text|您可以使用以下两种方法中的任何一种。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|166634|1)|166635|p+=+Polygon([(1,0),(1,1),(0,1),(0,0)])
for+x,y+in+p.exterior.coords:
+++print(x,y)|code-block|syntax|javascript|166636|上面的代码输出以下内容。注意，(1,0)被打印了两次，因为exterior.coords返回了一个完成多边形的有序序列。|166637|1.0+0.0
1.0+1.0
0.0+1.0
0.0+0.0
1.0+0.0|166638|2)|166639|p.exterior.coords.xy|166640|它输出以下内容|166641|(array('d',+[1.0,+1.0,+0.0,+0.0,+1.0]),+array('d',+[0.0,+1.0,+1.0,+0.0,+0.0]))|166642|entityMap^0|0|0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|W|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|X|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|Y|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|6|7|Z|8|@]|9|@]|A|$]]|$1|K|3|L|5|F|7|10|8|@]|9|@]|A|$G|H]]|$1|M|3|N|5|6|7|11|8|@]|9|@]|A|$]]|$1|O|3|P|5|F|7|12|8|@]|9|@]|A|$G|H]]|$1|Q|3|R|5|6|7|13|8|@]|9|@]|A|$]]|$1|S|3|T|5|F|7|14|8|@]|9|@]|A|$G|H]]|$1|U|3|-4|5|6|7|15|8|@]|9|@]|A|$]]]|V|$]]

You can use any of the two following methods.

1)

<pre><code>p = Polygon([(1,0),(1,1),(0,1),(0,0)])
for x,y in p.exterior.coords:
 print(x,y)
</code></pre>

The above code prints the following. Note that (1,0) is printed twice, since exterior.coords returns an ordered sequence that completes the polygon.

<pre><code>1.0 0.0
1.0 1.0
0.0 1.0
0.0 0.0
1.0 0.0
</code></pre>

2)

<pre><code>p.exterior.coords.xy
</code></pre>

It outputs the following

<pre><code>(array('d', [1.0, 1.0, 0.0, 0.0, 1.0]), array('d', [0.0, 1.0, 1.0, 0.0, 0.0]))
</code></pre>

blocks|key|168655|text|如果你真的想要组成多边形的有形状的点对象，而不仅仅是坐标元组，你可以这样做：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|168656|points+=+MultiPoint(polygon.boundary.coords)|code-block|syntax|javascript|168657|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

If you really want the shapely point objects that make up the polygon, and not just tuples of coordinates, you can do that this way:

<pre><code>points = MultiPoint(polygon.boundary.coords)
</code></pre>

blocks|key|166667|text|我花了一段时间才了解到，多边形有一个外部边界，也可能有几个内部边界。我之所以在这里发帖，是因为一些答案没有反映出这种区别，尽管公平地说，最初的帖子并没有使用内部边界的多边形作为示例。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|166668|形成外部边界的点排列在CoordinateSequence中，可以通过以下方式获得|166669|polygon.exterior.coords|code-block|syntax|javascript|166670|您可以使用len(polygon.exterior.coords)找到该对象的长度，并可以像列表一样对该对象进行索引。例如，要获取第一个顶点，请使用polygon.exterior.coords[0]。请注意，第一个点和最后一个点是相同的；如果您想要一个由不包含重复点的顶点组成的列表，请使用polygon.exterior.coords[:-1]。|offset|length|style|CODE|166671|可以将CoordinateSequence+(包括重复顶点)转化为点列表，如下所示：|166672|list(polygon.exterior.coords)|166673|类似地，由形成第一个内部边界的顶点组成的CoordinateSequence被获取为polygon.interiors[0].coords，并且这些顶点的列表(没有重复的点)被获取为polygon.interiors[0].coords[:-1]。|166674|entityMap^0|0|0|0|5|S|22|Q|42|S|0|0|0|16|R|2J|W|0^^$0|@$1|2|3|4|5|6|7|W|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|X|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|Y|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|6|7|Z|8|@$K|10|L|11|M|N]|$K|12|L|13|M|N]|$K|14|L|15|M|N]]|9|@]|A|$]]|$1|O|3|P|5|6|7|16|8|@]|9|@]|A|$]]|$1|Q|3|R|5|F|7|17|8|@]|9|@]|A|$G|H]]|$1|S|3|T|5|6|7|18|8|@$K|19|L|1A|M|N]|$K|1B|L|1C|M|N]]|9|@]|A|$]]|$1|U|3|-4|5|6|7|1D|8|@]|9|@]|A|$]]]|V|$]]

It took me a while to learn that a Polygon has an exterior boundary and possibly several interior boundaries. I am posting here because some of the answers don't reflect that distinction, though to be fair the original post did not use as an example a polygon with interior boundaries.

The points forming the exterior boundary are arranged in a CoordinateSequence, which can be obtained as

<pre><code>polygon.exterior.coords
</code></pre>

You can find the length of this object using <code>len(polygon.exterior.coords)</code>
and can index the object like a list. To get the first vertex, for example, use <code>polygon.exterior.coords[0]</code>. Note that the first and last points are the same; if you want a list consisting of the vertices without that repeated point, use <code>polygon.exterior.coords[:-1]</code>. 

You can convert the CoordinateSequence (including the repeated vertex) to a list of points thus:

<pre><code>list(polygon.exterior.coords)
</code></pre>

Similarly, the CoordinateSequence consisting of the vertices forming the first interior boundary is obtained as <code>polygon.interiors[0].coords</code>, and the list of those vertices (without the repeated point) is obtained as <code>polygon.interiors[0].coords[:-1]</code>.

How do you get/extract the points that define a <code>shapely</code> polygon?
Thanks!

Example of a shapely polygon

<pre><code>from shapely.geometry import Polygon

# Create polygon from lists of points
x = [list of x vals]
y = [list of y vals]

polygon = Polygon(x,y)
</code></pre>

Extract points/coordinates from a polygon in Shapely

如何获取/提取定义shapely多边形的点？谢谢!形状整齐的多边形的示例from shapely.geometry import Polygon# Create polygon from lists of pointsx = [list of x vals]y = [list of y vals]polygon = P...

问在Shapely中从多边形提取点/坐标
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