def split_matplotlib_cells(nb):
"""
If a cell imports matplotlib, split the cell to keep the
import statement separate from the code that uses matplotlib.
This prevents a known bug in the Jupyter backend which causes
the plot object to be represented as a string instead of a canvas
when created in the cell where matplotlib is imported for the
first time (https://github.com/jupyter/notebook/issues/3523).
"""
for i in range(len(nb['cells']) - 1, -1, -1):
cell = nb['cells'][i]
if cell['cell_type'] == 'code' and 'matplotlib' in cell['source']:
code = iw.protect_ipython_magics(cell['source'])
# split cells after matplotlib imports
mapping = iw.delimit_statements(code)
tree = ast.parse(code)
visitor = iw.GetMatplotlibPyplot()
visitor.visit(tree)
if visitor.matplotlib_first:
code = iw.deprotect_ipython_magics(code)
lines = code.split('\n')
lineno_end = mapping[visitor.matplotlib_first]
split_code = '\n'.join(lines[lineno_end:]).lstrip('\n')
if split_code:
new_cell = nbformat.v4.new_code_cell(source=split_code)
nb['cells'].insert(i + 1, new_cell)
lines = lines[:lineno_end]
nb['cells'][i]['source'] = '\n'.join(lines).rstrip('\n')
def test_ipython_magics(self):
lines = [
'%matplotlib inline',
'%%matplotlib notebook',
'import matplotlib.pyplot as plt',
'__doc__="%matplotlib inline"',
]
code = '\n'.join(lines)
code_protected = iw.protect_ipython_magics(code)
code_protected_ref = f'\n{code}'.replace(
'\n%', '\n#_IPYTHON_MAGIC_%')[1:]
self.assertEqual(code_protected, code_protected_ref)
code_deprotected = iw.deprotect_ipython_magics(code_protected)
self.assertEqual(code_deprotected, code)
# if matplotlib is used in this script, split cell to keep the import
# statement separate and avoid a known bug in the Jupyter backend which
# causes the plot object to be represented as a string instead of a
# canvas when created in the cell where matplotlib is imported for the
# first time (https://github.com/jupyter/notebook/issues/3523)
for i in range(len(nb['cells'])):
cell = nb['cells'][i]
if cell['cell_type'] == 'code' and 'matplotlib' in cell['source']:
code = iw.protect_ipython_magics(cell['source'])
# split cells after matplotlib imports
mapping = iw.delimit_statements(code)
tree = ast.parse(code)
visitor = iw.GetMatplotlibPyplot()
visitor.visit(tree)
if visitor.matplotlib_first:
code = iw.deprotect_ipython_magics(code)
lines = code.split('\n')
lineno_end = mapping[visitor.matplotlib_first]
split_code = '\n'.join(lines[lineno_end:]).lstrip('\n')
if split_code:
new_cell = nbformat.v4.new_code_cell(source=split_code)
nb['cells'].insert(i + 1, new_cell)
lines = lines[:lineno_end]
nb['cells'][i]['source'] = '\n'.join(lines).rstrip('\n')
break
# substitute global variables and disable OpenGL/Mayavi GUI
cell_separator = '\n##{}\n'.format(uuid.uuid4().hex)
src = cell_separator.join(get_code_cells(nb))
parameters = dict(x.split('=', 1) for x in new_values)
src = iw.substitute_variable_values(src, strings_as_is=True,