从列表中删除引号 - Python答案

【问题标题】：Remove quotes from list - Python从列表中删除引号 - Python
【发布时间】：2020-04-05 21:54:37
【问题描述】：

我有以下字符串，其中包含不同 poligons 的坐标[x,y],[x,y]...

test3 = [(39.414604,-7.021836),(39.814045,-4.073939),(41.315235,-4.384754),(40.917038,-7.398971),(39.414604,-7.021836)],[(38.844185,-4.804621),(39.241299,-1.899833),(40.74308,-2.205491),(40.34742,-5.17429),(38.844185,-4.804621)],[(40.347511,-5.174313),(40.743309,-2.20434),(42.242691,-2.530139),(41.847603,-5.569263),(40.347511,-5.174313)],[(39.365192,-1.941078),(40.867912,-1.567062),(41.276688,-4.670904),(39.775406,-4.976737),(39.365192,-1.941078)],[(39.706161,-1.849863),(41.207623,-1.465817),(41.617561,-4.594476),(40.117233,-4.908839),(39.706161,-1.849863)],[(39.702591,-5.033657),(40.101254,-2.077048),(41.602196,-2.389729),(41.204681,-5.413605),(39.702591,-5.033657)],[(40.502308,-3.713448),(42.002708,-3.320609),(42.411217,-6.481188),(40.911678,-6.801756),(40.502308,-3.713448)],[(38.999126,-4.084739),(40.50222,-3.713471),(40.911449,-6.800602),(39.409878,-7.104931),(38.999126,-4.084739)],[(39.706161,-1.849863),(41.207623,-1.465817),(41.617561,-4.594476),(40.117233,-4.908839),(39.706161,-1.849863)]

当检查test3的输出时，它带有'和'' at the begining and end (this can be avoided by usingprint(test3)`

> test3
'[(39.414604,-7.021836),(39.814045,-4.073939),(41.315235,-4.384754),(40.917038,-7.398971),(39.414604,-7.021836)],[(38.844185,-4.804621),(39.241299,-1.899833),(40.74308,-2.205491),(40.34742,-5.17429),(38.844185,-4.804621)],[(40.347511,-5.174313),(40.743309,-2.20434),(42.242691,-2.530139),(41.847603,-5.569263),(40.347511,-5.174313)],[(39.365192,-1.941078),(40.867912,-1.567062),(41.276688,-4.670904),(39.775406,-4.976737),(39.365192,-1.941078)],[(39.706161,-1.849863),(41.207623,-1.465817),(41.617561,-4.594476),(40.117233,-4.908839),(39.706161,-1.849863)],[(39.702591,-5.033657),(40.101254,-2.077048),(41.602196,-2.389729),(41.204681,-5.413605),(39.702591,-5.033657)],[(40.502308,-3.713448),(42.002708,-3.320609),(42.411217,-6.481188),(40.911678,-6.801756),(40.502308,-3.713448)],[(38.999126,-4.084739),(40.50222,-3.713471),(40.911449,-6.800602),(39.409878,-7.104931),(38.999126,-4.084739)],[(39.706161,-1.849863),(41.207623,-1.465817),(41.617561,-4.594476),(40.117233,-4.908839),(39.706161,-1.849863)]'

我想用这个字符串作为坐标信息来绘制交互式地图中的多边形。为此，我使用以下代码，特别是需要 list 输入的 locations 参数

from ipyleaflet import Map, Polygon

polygon = Polygon(
    locations=[test3],
    color="green",
    fill_opacity= 0.5,
    fill_color="green"
)

m = Map(center=(38.5531, -4.6914), zoom=6)
m.add_layer(polygon);
m

问题在于[test3] 等于：（注意开头的['[ 和结尾的]']

['[(39.414604,-7.021836),(39.814045,-4.073939),(41.315235,-4.384754),(40.917038,-7.398971),(39.414604,-7.021836)],[(38.844185,-4.804621),(39.241299,-1.899833),(40.74308,-2.205491),(40.34742,-5.17429),(38.844185,-4.804621)],[(40.347511,-5.174313),(40.743309,-2.20434),(42.242691,-2.530139),(41.847603,-5.569263),(40.347511,-5.174313)],[(39.365192,-1.941078),(40.867912,-1.567062),(41.276688,-4.670904),(39.775406,-4.976737),(39.365192,-1.941078)],[(39.706161,-1.849863),(41.207623,-1.465817),(41.617561,-4.594476),(40.117233,-4.908839),(39.706161,-1.849863)],[(39.702591,-5.033657),(40.101254,-2.077048),(41.602196,-2.389729),(41.204681,-5.413605),(39.702591,-5.033657)],[(40.502308,-3.713448),(42.002708,-3.320609),(42.411217,-6.481188),(40.911678,-6.801756),(40.502308,-3.713448)],[(38.999126,-4.084739),(40.50222,-3.713471),(40.911449,-6.800602),(39.409878,-7.104931),(38.999126,-4.084739)],[(39.706161,-1.849863),(41.207623,-1.465817),(41.617561,-4.594476),(40.117233,-4.908839),(39.706161,-1.849863)]']

我的问题是：如何在test3 的开头和结尾去掉那个'，以便在执行[test3] 时，输入正确 - as [[x,y],[x,y],...,[x,y]]

-- 编辑-- test3 去哪了？

以dataframe开头：

df['Footprint']
0    MULTIPOLYGON (((-6.854965 38.740932,-3.940099 ...
1    MULTIPOLYGON (((-7.021836 39.414604,-4.073939 ...
2    MULTIPOLYGON (((-4.804621 38.844185,-1.899833 ...
3    MULTIPOLYGON (((-5.174313 40.347511,-2.20434 4...
4    MULTIPOLYGON (((-1.941078 39.365192,-1.567062 ...
5    MULTIPOLYGON (((-1.849863 39.706161,-1.465817 ...
6    MULTIPOLYGON (((-5.033657 39.702591,-2.077048 ...
7    MULTIPOLYGON (((-3.713448 40.502308,-3.320609 ...
8    MULTIPOLYGON (((-4.084739 38.999126,-3.713471 ...
9    MULTIPOLYGON (((-3.870231 39.827106,-3.49322 4...
Name: Footprint, dtype: object

接下来，我将坐标的顺序从(x,y)倒转为(y,x)

test2 =  df['Footprint'].map(lambda polygon: shapely.ops.transform(lambda x, y: (y, x), shapely.wkt.loads(polygon)))
test2

0    (POLYGON ((38.740932 -6.854965, 39.140369 -3.9...
1    (POLYGON ((39.414604 -7.021836, 39.814045 -4.0...
2    (POLYGON ((38.844185 -4.804621, 39.241299 -1.8...
3    (POLYGON ((40.347511 -5.174313, 40.743309 -2.2...
4    (POLYGON ((39.365192 -1.941078, 40.867912 -1.5...
5    (POLYGON ((39.706161 -1.849863, 41.207623 -1.4...
6    (POLYGON ((39.702591 -5.033657, 40.101254 -2.0...
7    (POLYGON ((40.502308 -3.713448, 42.002708 -3.3...
8    (POLYGON ((38.999126 -4.084739, 40.50222 -3.71...
9    (POLYGON ((39.827106 -3.870231, 41.329609 -3.4...
Name: Footprint, dtype: object

接下来，我创建一个包含坐标的字符串列表：

geom_str = []
for i in test2:  # same for multipolygon.geoms
    test = str(i)
    geom_str.append(test)
geom_str

['MULTIPOLYGON (((38.740932 -6.854965, 39.140369 -3.940099, 40.6422 -4.245644, 40.244202 -7.224669, 38.740932 -6.854965)))',
 'MULTIPOLYGON (((39.414604 -7.021836, 39.814045 -4.073939, 41.315235 -4.384754, 40.917038 -7.398971, 39.414604 -7.021836)))',
 'MULTIPOLYGON (((38.844185 -4.804621, 39.241299 -1.899833, 40.74308 -2.205491, 40.34742 -5.17429, 38.844185 -4.804621)))',
 'MULTIPOLYGON (((40.347511 -5.174313, 40.743309 -2.20434, 42.242691 -2.530139, 41.847603 -5.569263, 40.347511 -5.174313)))',
 'MULTIPOLYGON (((39.365192 -1.941078, 40.867912 -1.567062, 41.276688 -4.670904, 39.775406 -4.976737, 39.365192 -1.941078)))',
 'MULTIPOLYGON (((39.706161 -1.849863, 41.207623 -1.465817, 41.617561 -4.594476, 40.117233 -4.908839, 39.706161 -1.849863)))',
 'MULTIPOLYGON (((39.702591 -5.033657, 40.101254 -2.077048, 41.602196 -2.389729, 41.204681 -5.413605, 39.702591 -5.033657)))',
 'MULTIPOLYGON (((40.502308 -3.713448, 42.002708 -3.320609, 42.411217 -6.481188, 40.911678 -6.801756, 40.502308 -3.713448)))',
 'MULTIPOLYGON (((38.999126 -4.084739, 40.50222 -3.713471, 40.911449 -6.800602, 39.409878 -7.104931, 38.999126 -4.084739)))',
 'MULTIPOLYGON (((39.827106 -3.870231, 41.329609 -3.49322, 41.739006 -6.624273, 40.237854 -6.931492, 39.827106 -3.870231)))']

接下来，我删除了一些不必要的字符：

extent = []

for i in range(len(geom_str)):
    test = geom_str[i]
    test = test.replace('MULTIPOLYGON (((', '(')
    test = test.replace(')))', ')')
    test = test.replace(', ', ')')
    test = test.replace(')', '),(')
    test = test.replace(' ', ',')
    test = str(test)[:-2]
    extent.append(test)

extent
['(38.740932,-6.854965),(39.140369,-3.940099),(40.6422,-4.245644),(40.244202,-7.224669),(38.740932,-6.854965)',
 '(39.414604,-7.021836),(39.814045,-4.073939),(41.315235,-4.384754),(40.917038,-7.398971),(39.414604,-7.021836)',
 '(38.844185,-4.804621),(39.241299,-1.899833),(40.74308,-2.205491),(40.34742,-5.17429),(38.844185,-4.804621)',
 '(40.347511,-5.174313),(40.743309,-2.20434),(42.242691,-2.530139),(41.847603,-5.569263),(40.347511,-5.174313)',
 '(39.365192,-1.941078),(40.867912,-1.567062),(41.276688,-4.670904),(39.775406,-4.976737),(39.365192,-1.941078)',
 '(39.706161,-1.849863),(41.207623,-1.465817),(41.617561,-4.594476),(40.117233,-4.908839),(39.706161,-1.849863)',
 '(39.702591,-5.033657),(40.101254,-2.077048),(41.602196,-2.389729),(41.204681,-5.413605),(39.702591,-5.033657)',
 '(40.502308,-3.713448),(42.002708,-3.320609),(42.411217,-6.481188),(40.911678,-6.801756),(40.502308,-3.713448)',
 '(38.999126,-4.084739),(40.50222,-3.713471),(40.911449,-6.800602),(39.409878,-7.104931),(38.999126,-4.084739)',
 '(39.827106,-3.870231),(41.329609,-3.49322),(41.739006,-6.624273),(40.237854,-6.931492),(39.827106,-3.870231)']

接下来，我在每个 (x,y) 坐标的开头添加[]：

extent2 = []

for i in range(len(extent)):
    test = '[' + extent[i] + '],'
    extent2.append(test)

接下来，我在最后删除一些不必要的字符：

extent2[len(extent2)-1] = str(extent2[5])[:-1]

接下来，我将所有索引连接在一起（此步骤我想在 FOR LOOP 中进行转换）

test = [extent2[1]+extent2[2]+extent2[3]+extent2[4]+extent2[5]+extent2[6]+extent2[7]+extent2[8]+extent2[9]]

最后，我得到了test3，如下：

test3 = str(test).replace("['[", '[')
test3 = str(test3).replace("]']", ']')
test3

【问题讨论】：

test3 = eval(test3) ?
test3 来自哪里？你真的像问题开头那样定义它吗？
@ArcturusB 我已添加并编辑问题以显示 test3 的来源。
@CDJB 很好的解决方案。我已经编辑了问题以添加 test3 的来源，以防我可以在清理/准备数据时解决此问题。
@GCGM 鉴于您已经拥有该代码，我会说这是最好的方法 - 可能有一个函数可以从 Polygon 对象中提取坐标作为元组，但最好发布作为另一个问题。很高兴它有帮助:)

标签： python list

【解决方案1】：

我认为以字符串格式操作数据是一种不好的做法：

如果我以你的例子为例，你应该找出“i”的类型（在下面的 for 循环中），而不是转换为字符串。

geom_str = []
for i in test2:  # same for multipolygon.geoms
    print(type(i), i) # <- What happens here ? Is i a list ? a tuple ?
    test = str(i) 
    geom_str.append(test)
geom_str

你能不能试着在for循环中查看这个“i”的类型，以及如果你打印它得到的值。一旦我知道它的样子，我会尽快为您处理这些数据。

【讨论】：

我不是很舒服地操作为字符串，但我想不出另一种解决方案来实现我在ipyleaflet 地图中绘制多面体的最终目标。 i 之一的输出是：<class 'shapely.geometry.multipolygon.MultiPolygon'> MULTIPOLYGON (((40.347511 -5.174313, 40.743309 -2.20434, 42.242691 -2.530139, 41.847603 -5.569263, 40.347511 -5.174313)))
好的，既然是类实例，你需要检查它的属性。尝试打印 i.bounds 以查看是否可以在不使用函数 str() 的情况下获得这些值 (40.347511 -5.174313...)。如果这个属性不起作用，那么你可以 print(i.__dict__) 来查看这个实例的所有属性，但遗憾的是会有很多。或查看shapely.readthedocs.io/en/stable/manual.html 了解有关 MultiPolygon 类的更多信息
我真的不知道为什么我之前没有遇到.bound。现在没有时间完整地测试它，但通过第一次试验，我认为它可以避免像str 那样操作数据，我已经为此受了很多苦。稍后我会检查并通知您
终于有时间测试了。最后我没有使用.bound 而是使用mapping 从shapely 对象中提取坐标。这使我可以避免将它们操作为string。感谢您为我指明了正确的方向。对论坛的首次贡献：)
很高兴您找到了一种无需字符串操作的方法！谢谢，很高兴能提供帮助:)

【解决方案2】：

这是 API 响应数据或 JSON 的序列化数据。

为您的问题尝试以下解决方案。

import json

json.loads(<pass your data over here>)

它将您的数据转换为实际列表或任何字典对象。

【讨论】：

你的意思是json.loads(test3)？使用该代码我得到错误：JSONDecodeError: Expecting value: line 1 column 2 (char 1)

【解决方案3】：

您可以使用 Python 内置函数 eval() 将表示列表或元组的字符串评估为该对象。

test3 = eval(test3)

【讨论】：

也可以，但我更喜欢@phoenixo 提供的选项，因为我避免将坐标操作为string
@GCGM 是的，我想这可能是一个 X Y 问题！很高兴您找到了解决方案。