matplotlib's rcParams['figure.figsize'] lost between cells

I can set the size of figures like this:

# In[1]:
import matplotlib.pyplot as plt
import numpy as np

%matplotlib inline

x = np.linspace(0, 6, 200)
y = np.sin(x)

# In[2]:
# Set figures to be large
plt.rcParams['figure.figsize'] = (10, 10)
plt.plot(x, y);

In the above example, the rcParams[‘figure.figsize’] is set in cell 2 (where the plot is made), and the figure is correctly sized to 10 x 10.

However, if I try setting the figure size in cell 1, it is ignored. The figure remains the default size…

# In[1]:
import matplotlib.pyplot as plt
import numpy as np

%matplotlib inline

x = np.linspace(0, 6, 200)
y = np.sin(x)

# Set figures to be large
plt.rcParams['figure.figsize'] = (10, 10)

# In[2]:
plt.plot(x, y);

Settings in rcParams used to work. It must be an updated version of ipython or matplotlib which has broken the memory of rcParams between cells.

The output of pandas.show_versions() is:

INSTALLED VERSIONS
------------------
commit: None
python: 3.6.4.final.0
python-bits: 64
OS: Windows
OS-release: 10
machine: AMD64
processor: Intel64 Family 6 Model 94 Stepping 3, GenuineIntel
byteorder: little
LC_ALL: None
LANG: None
LOCALE: None.None

pandas: 0.22.0
pytest: 3.2.1
pip: 9.0.1
setuptools: 36.5.0.post20170921
Cython: 0.26.1
numpy: 1.13.3
scipy: 1.0.0
pyarrow: None
xarray: None
IPython: 6.2.1
sphinx: 1.6.3
patsy: 0.4.1
dateutil: 2.6.1
pytz: 2017.2
blosc: None
bottleneck: 1.2.1
tables: 3.4.2
numexpr: 2.6.2
feather: None
matplotlib: 2.2.2
openpyxl: 2.4.8
xlrd: 1.1.0
xlwt: 1.3.0
xlsxwriter: 0.9.8
lxml: 3.8.0
bs4: 4.6.0
html5lib: 0.999999999
sqlalchemy: 1.1.13
pymysql: None
psycopg2: None
jinja2: 2.9.6
s3fs: None
fastparquet: None
pandas_gbq: None
pandas_datareader: None

[mapio]

For me this happens if I put import matplotlib.pylab as plt in the same cell as plt.rcParams['figure.figsize'] = … but not if I put it in two cells.

 

[germannp]

For me it is even weirder:

But if I run everything again, it works:

• Windows 10 Enterprise, 1803
• Matplotlib 2.2.3
• Python 3.7.0
• JupyterLab 0.34.9