[BUG/ISSUE] AttributeError: 'GeoAxesSubplot' object has no attribute '_hold'

[jinlx]

Hi there,

I am trying to follow the python tutorial to get some basic plots. However, I get traceback below. Also, my code is attached below just in case.

failed to get the current screen resources
Traceback (most recent call last):
  File "panel_CO.py", line 47, in <module>
    co.plot(ax=ax,cmap=WhGrYlRd)
  File "/glade/u/home/lixujin/anaconda3/envs/geoschem/lib/python3.6/site-packages/xarray/plot/plot.py", line 552, in __call__
    return plot(self._da, **kwargs)
  File "/glade/u/home/lixujin/anaconda3/envs/geoschem/lib/python3.6/site-packages/xarray/plot/plot.py", line 187, in plot
    return plotfunc(darray, **kwargs)
  File "/glade/u/home/lixujin/anaconda3/envs/geoschem/lib/python3.6/site-packages/xarray/plot/plot.py", line 854, in newplotfunc
    **kwargs)
  File "/glade/u/home/lixujin/anaconda3/envs/geoschem/lib/python3.6/site-packages/xarray/plot/plot.py", line 1108, in pcolormesh
    primitive = ax.pcolormesh(x, y, z, **kwargs)
  File "/glade/u/home/lixujin/anaconda3/envs/geoschem/lib/python3.6/site-packages/cartopy/mpl/geoaxes.py", line 1451, in pcolormesh
    result = self._pcolormesh_patched(*args, **kwargs)
  File "/glade/u/home/lixujin/anaconda3/envs/geoschem/lib/python3.6/site-packages/cartopy/mpl/geoaxes.py", line 1469, in _pcolormesh_patched
    if not self._hold:
AttributeError: 'GeoAxesSubplot' object has no attribute '_hold'

Code

# Read data and print out to see the structure
# Pay attention to unit conversion
# Author: Lixu Jin
# Version: GEOS-CHEM 12.2.1, 09/15/2019

# import packages
#from mpl_toolkits.basemap import Basemap

from gamap_colormap import WhGrYlRd
import cartopy.crs as ccrs
import xbpch
import matplotlib.pyplot as plt
import xarray as xr    
import numpy as np
from matplotlib.colors import LogNorm

plt.style.use(['seaborn-talk', 'seaborn-ticks'])

#=============================================================
# Read single dataset
#=============================================================
# Read data
filedir = '/glade/u/home/lixujin/project/GEOS-CHEM/ExtData/HEMCO/GFAS/v2018-09/2018/'
data1 = 'GFAS_201807.nc'
data2 = 'GFAS_201808.nc'
data3 = 'GFAS_201809.nc'
ds1 = xr.open_dataset(filedir + data1)
ds2 = xr.open_dataset(filedir + data2)
ds3 = xr.open_dataset(filedir + data3)
#============================================================
# calculation part
#============================================================
# sum up druing we-can period
co = 60*60*24*1e3*(ds1['cofire'].sum('time') + ds2['cofire'].sum('time') + ds3['cofire'].sum('time'))
co.attrs['unit'] = 'ppm'
print(co)
print(type(co))

# fig setting
# empty map.
fig = plt.figure(figsize=(8,4))

# without this, it would be super wired.
ax = plt.axes(projection=ccrs.PlateCarree())
ax.coastlines()
ax.set_title('global CO during wecan period')

co.plot(ax=ax,cmap=WhGrYlRd)

#fig.plot(cmap='gist_stern') # The ax keyword is particularly useful for subplots. Can be omitted here.
fig.savefig('co_global1.jpg')

[yantosca]

Thanks for writing. I googled this error and came across these links:

SciTools/cartopy#1120
http://ytukyg.blogspot.com/2019/01/cartopy-problem-with-pcolormesh.html

They suggest you might need to update your matplotlib version. The versions that I am using on my system are listed below:

------------------
platform        : Linux-3.10.0-957.12.1.el7.x86_64-x86_64-with-centos-7.6.1810-Core
python          : 3.6.9

VERSION NUMBERS FOR GCPy DEPENDENCIES
-------------------------------------

bottleneck      : 1.2.1
cartopy         : 0.17.0
cython          : 0.29.13
dask            : 2.3.0
graphviz        : 0.10.1
future          : 0.17.1
h5netcdf        : 0.6.2
h5py            : 2.8.0
h5pyd           : 0.3.3
IPython         : 7.7.0
matplotlib      : 3.1.1
netCDF4         : 1.4.2
notebook        : 6.0.0
numpy           : 1.16.4
pandas          : 0.25.1
pip             : 19.2.2
pycodestyle     : 2.4.0
pyresample      : 1.10.3
pytest          : 4.2.0
scipy           : 1.3.1
seaborn         : 0.9.0
setuptools      : 41.2.0
six             : 1.12.0
sphinx          : 2.1.2
xbpch           : 0.3.5
xarray          : 0.12.1
xesmf           : 0.2.0

[jinlx]

Bob-thanks. I set up the environment again and it works. I think I found the reason why this AttributeError happens now. After setting up the gcpy environment, I also install the basemap package. And it will automatically downgrade some packages like cartopy and proj4, causing this attributerro eventually.

Lixu

[yantosca]

Thanks for the reply. I'll go ahead and close this out. Glad it works!!