如何在地理 hvplot 点 plot 上叠加文本标签？

Question

我正在尝试将标签添加到显示平铺 map 上的点的 hvplot 中。

我的 GeoDataFrame gdf看起来像这样：

  id                  geometry
8911  POINT (5.79557 53.20121)
8912  POINT (5.76973 53.18031)
8913  POINT (5.78159 53.20088)
8914  POINT (5.75442 53.20394)
8915  POINT (5.76594 53.21173)

将这些点添加到 map 很容易：

gdf.hvplot(geo=True, tiles=True)

然后我尝试以类似的方式对 plot 文本标签使用标签，但这不起作用。：

gdf.hvplot.labels(geo=True, tiles=True, text='id')

它给了我这个错误

Traceback (most recent call last):

  File "<ipython-input-138-73570b6a686e>", line 1, in <module>
    centroid_labels = dfl.hvplot.labels(geo=True, tiles=True, text='id')

  File "C:\Users\user\Miniconda3\envs\otp\lib\site-packages\hvplot\plotting\core.py", line 574, in labels
    return self(x, y, text=text, kind='labels', **kwds)

  File "C:\Users\user\Miniconda3\envs\otp\lib\site-packages\hvplot\plotting\core.py", line 79, in __call__
    return self._get_converter(x, y, kind, **kwds)(kind, x, y)

  File "C:\Users\user\Miniconda3\envs\otp\lib\site-packages\hvplot\converter.py", line 1097, in __call__
    obj = method(x, y)

  File "C:\Users\user\Miniconda3\envs\otp\lib\site-packages\hvplot\converter.py", line 1688, in labels
    text = self.kwds.get('text', [c for c in data.columns if c not in (x, y)][0])

IndexError: list index out of range

显式添加x和y选项会产生不同的错误：

gdf.hvplot.labels(geo=True, tiles=True, x=gdf.geometry.x, y=gdf.geometry.y, text='id')

Traceback (most recent call last):

  File "<ipython-input-143-0eaefd24cbe6>", line 1, in <module>
    centroid_labels = dfl.hvplot.labels(geo=True, x=dfl.geometry.x, y=dfl.geometry.y, tiles=True, text='id')

  File "C:\Users\user\Miniconda3\envs\otp\lib\site-packages\hvplot\plotting\core.py", line 574, in labels
    return self(x, y, text=text, kind='labels', **kwds)

  File "C:\Users\user\Miniconda3\envs\otp\lib\site-packages\hvplot\plotting\core.py", line 79, in __call__
    return self._get_converter(x, y, kind, **kwds)(kind, x, y)

  File "C:\Users\user\Miniconda3\envs\otp\lib\site-packages\hvplot\plotting\core.py", line 83, in _get_converter
    x = x or params.pop('x', None)

  File "C:\Users\user\Miniconda3\envs\otp\lib\site-packages\pandas\core\generic.py", line 1442, in __nonzero__
    raise ValueError(

ValueError: The truth value of a Series is ambiguous. Use a.empty, a.bool(), a.item(), a.any() or a.all().

Answer 1

我能够通过将 CRS 转换为EPSG:3857 ( WGS 84 / Pseudo-Mercator ) 来实现这一点，这可能适合也可能不适合您的目的。

附带说明一下，如果有一个关于此类问题的MRE ，那就太好了。

这是有效的：

import geopandas as gpd
import pandas as pd
import hvplot.pandas
import geoviews as gv
from geoviews import tile_sources as gvts

raw = """8911  POINT (5.79557 53.20121)
8912  POINT (5.76973 53.18031)
8913  POINT (5.78159 53.20088)
8914  POINT (5.75442 53.20394)
8915  POINT (5.76594 53.21173)"""

data = [(_[0], _[-2], _[-1]) for _ in [_.replace("(", "").replace(")", "").split() for _ in raw.split("\n")]]
df = pd.DataFrame(data, columns=["labels", "x", "y"]).astype({"labels": str})
gdf = gpd.GeoDataFrame(df, geometry=gpd.points_from_xy(df.x, df.y, crs="EPSG:4326"))

tiles = gvts.CartoLight
points = gdf.hvplot(geo=True, tiles="CartoLight")
labels = gdf.to_crs("EPSG:3857").assign(x=lambda df: df.geometry.x, y=lambda df: df.geometry.y).hvplot.labels(text="labels", x="x", y="y")
(points * labels * tiles).opts(height=600, width=800)

我认为这应该有效：

gdf.hvplot.labels(text="labels", geo=True)

这真的只是解决原始问题，可能值得在 github 上报告该问题。