Attribute joins are accomplished using the merge() method. In general, it is recommended to use the merge() method called from the spatial dataset. With that said, the stand-alone pandas.merge() function will work if the GeoDataFrame is in the left argument; if a DataFrame is in the left argument and a GeoDataFrame is in the right position, the result will no longer be a GeoDataFrame.

属性连接使用 merge() 方法完成。一般来说，建议使用通过空间数据集调用 merge() 方法。话虽如此，如果 GeoDataFrame 在左侧参数中，则独立的 pandas.merge() 函数将起作用；如果 DataFrame 在左边的参数中， GeoDataFrame 在右边的位置，则结果将不再是 GeoDataFrame。

For example, consider the following merge that adds full names to a GeoDataFrame that initially has only ISO codes for each country by merging it with a DataFrame.

例如，考虑以下合并，将全名添加到 GeoDataFrame，该 GeoDataFrame 最初只有每个国家/地区的 ISO 代码。

# `country_shapes` is GeoDataFrame with country shapes and iso codes
In [11]: country_shapes.head()
Out[11]: 
                                            geometry iso_a3
0  MULTIPOLYGON (((180.000000000 -16.067132664, 1...    FJI
1  POLYGON ((33.903711197 -0.950000000, 34.072620...    TZA
2  POLYGON ((-8.665589565 27.656425890, -8.665124...    ESH
3  MULTIPOLYGON (((-122.840000000 49.000000000, -...    CAN
4  MULTIPOLYGON (((-122.840000000 49.000000000, -...    USA

# `country_names` is DataFrame with country names and iso codes
In [12]: country_names.head()
Out[12]: 
                       name iso_a3
0                      Fiji    FJI
1                  Tanzania    TZA
2                 W. Sahara    ESH
3                    Canada    CAN
4  United States of America    USA

# Merge with `merge` method on shared variable (iso codes):
In [13]: country_shapes = country_shapes.merge(country_names, on='iso_a3')

In [14]: country_shapes.head()
Out[14]: 
                                            geometry  ...                      name
0  MULTIPOLYGON (((180.000000000 -16.067132664, 1...  ...                      Fiji
1  POLYGON ((33.903711197 -0.950000000, 34.072620...  ...                  Tanzania
2  POLYGON ((-8.665589565 27.656425890, -8.665124...  ...                 W. Sahara
3  MULTIPOLYGON (((-122.840000000 49.000000000, -...  ...                    Canada
4  MULTIPOLYGON (((-122.840000000 49.000000000, -...  ...  United States of America

[5 rows x 3 columns]