我有 12 张使用 cartopy 的地图，我想使用 plt.subplots 制作地图的网格显示4 行 3 列

如何解决我有 12 张使用 cartopy 的地图，我想使用 plt.subplots 制作地图的网格显示4 行 3 列

我有 12 张 cartopy 地图，我想将它们组织成 3 行 4 列，以便更容易看到它们，而不仅仅是垂直绘制。 我尝试使用 fig,ax = plt.subplots 并使用 ax.ravel 但我不断收到此错误。我也尝试更新cartopy，但错误仍然存​​在：

fig,ax = plt.subplots(nrows=3,ncols=4,figsize=(15,5))
    for i in zip(range(12),ax.ravel()):
        ax = plt.axes(projection=ccrs.PlateCarree())
        ax.set_extent([-90,10,5,85],crs=ccrs.PlateCarree())
        x = ax.contourf(longitude,latitude,climatology[i],np.arange(28,39,.3),cmap='jet',ax=ax,extend='both')
        ax.coastlines()
        #ax.add_feature(cfeature.LAND,zorder=100,edgecolor='k')
        gridlines = ax.gridlines(draw_labels=True)
        cbar = plt.colorbar(x,fraction=.046,pad=0.04)
        cbar.set_label('psu',labelpad=15,y=.5,rotation=90)
        ax.text(.5,-.12,'Longitude',va='bottom',ha='center',rotation='horizontal',rotation_mode= 'anchor',transform=ax.transAxes)
        ax.text(-.1,.5,'Latitude',rotation='vertical',transform=ax.transAxes)
        #plt.title(title)
        plt.show()

错误：

---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
<ipython-input-57-4fa6b08f3ee5> in <module>
      3     ax = plt.axes(projection=ccrs.PlateCarree())
      4     ax.set_extent([-90,crs=ccrs.PlateCarree())
----> 5     x = ax.contourf(sss_md.longitude,sss_md.latitude,extend='both')
      6     ax.coastlines()
      7     #ax.add_feature(cfeature.LAND,edgecolor='k')

~/miniconda3/envs/py3_std_maps/lib/python3.8/site-packages/xarray/core/dataarray.py in __getitem__(self,key)
    640         else:
    641             # xarray-style array indexing
--> 642             return self.isel(indexers=self._item_key_to_dict(key))
    643 
    644     def __setitem__(self,key: Any,value: Any) -> None:

~/miniconda3/envs/py3_std_maps/lib/python3.8/site-packages/xarray/core/dataarray.py in isel(self,indexers,drop,missing_dims,**indexers_kwargs)
   1037 
   1038         if any(is_fancy_indexer(idx) for idx in indexers.values()):
-> 1039             ds = self._to_temp_dataset()._isel_fancy(
   1040                 indexers,drop=drop,missing_dims=missing_dims
   1041             )

~/miniconda3/envs/py3_std_maps/lib/python3.8/site-packages/xarray/core/dataset.py in _isel_fancy(self,missing_dims)
   2011 
   2012             if name in self.indexes:
-> 2013                 new_var,new_index = isel_variable_and_index(
   2014                     name,var,self.indexes[name],var_indexers
   2015                 )

~/miniconda3/envs/py3_std_maps/lib/python3.8/site-packages/xarray/core/indexes.py in isel_variable_and_index(name,variable,index,indexers)
    104         )
    105 
--> 106     new_variable = variable.isel(indexers)
    107 
    108     if new_variable.dims != (name,):

~/miniconda3/envs/py3_std_maps/lib/python3.8/site-packages/xarray/core/variable.py in isel(self,**indexers_kwargs)
   1116 
   1117         key = tuple(indexers.get(dim,slice(None)) for dim in self.dims)
-> 1118         return self[key]
   1119 
   1120     def squeeze(self,dim=None):

~/miniconda3/envs/py3_std_maps/lib/python3.8/site-packages/xarray/core/variable.py in __getitem__(self,key)
    764         array `x.values` directly.
    765         """
--> 766         dims,indexer,new_order = self._broadcast_indexes(key)
    767         data = as_indexable(self._data)[indexer]
    768         if new_order:

~/miniconda3/envs/py3_std_maps/lib/python3.8/site-packages/xarray/core/variable.py in _broadcast_indexes(self,key)
    610         # key can be mapped as an OuterIndexer.
    611         if all(not isinstance(k,Variable) for k in key):
--> 612             return self._broadcast_indexes_outer(key)
    613 
    614         # If all key is 1-dimensional and there are no duplicate labels,~/miniconda3/envs/py3_std_maps/lib/python3.8/site-packages/xarray/core/variable.py in _broadcast_indexes_outer(self,key)
    686             new_key.append(k)
    687 
--> 688         return dims,OuterIndexer(tuple(new_key)),None
    689 
    690     def _nonzero(self):

~/miniconda3/envs/py3_std_maps/lib/python3.8/site-packages/xarray/core/indexing.py in __init__(self,key)
    407             elif isinstance(k,np.ndarray):
    408                 if not np.issubdtype(k.dtype,np.integer):
--> 409                     raise TypeError(
    410                         f"invalid indexer array,does not have integer dtype: {k!r}"
    411                     )

TypeError: invalid indexer array,does not have integer dtype: array(<AxesSubplot:>,dtype=object)

解决方法

试试这个编辑过的代码。请注意，投影应声明为 subplot_kw 的一部分。

import matplotlib.pyplot as plt
import cartopy.crs as ccrs

fig,axes = plt.subplots(nrows=3,ncols=4,figsize=(18,10),subplot_kw=dict(projection=ccrs.PlateCarree()))

for i,ax in zip(range(12),axes.ravel()):
# (or) for i,ax in enumerate(axes.flat):
    # (NOT this) ax = plt.axes(projection=ccrs.PlateCarree())
    ax.set_extent([-90,10,5,85],crs=ccrs.PlateCarree())

    ax.coastlines(lw=0.2)
    # (plot land) ax.add_feature(cfeature.LAND,zorder=100,edgecolor='k')
    gridlines = ax.gridlines(draw_labels=True)
    # cbar = plt.colorbar(x,fraction=.046,pad=0.04)
    # cbar.set_label('psu',labelpad=15,y=.5,rotation=90)
    ax.text(.5,-.12,'Longitude',va='bottom',ha='center',rotation='horizontal',rotation_mode= 'anchor',transform=ax.transAxes)
    ax.text(-.1,.5,'Latitude',rotation='vertical',transform=ax.transAxes)
    # plt.title(title)

plt.show()  # place this outside the `for-loop`

输出图：