Post-Mortem Python Plotting
https://andyljones.com/posts/post-mortem-plotting.html
Python | TutorialThe extract
function copies the local variables from the current function frame into the existing Jupyter session. If the Python code crashes, you can enter the debugger with the %debug
magic and then use the extract
function to copy the variables from the function frame into the Jupyter session. The variables can now be properly inspected, e.g., plotted.
The original URI above contains more details how to use this post-mortem debugging.
def extract(source=None):
"""Copies the variables of the caller up to iPython. Useful for debugging.
.. code-block:: python
def f():
x = 'hello world'
extract()
f() # raises an error
print(x) # prints 'hello world'
"""
import inspect
import ctypes
if source is None:
frames = inspect.stack()
caller = frames[1].frame
name, ls, gs = caller.f_code.co_name, caller.f_locals, caller.f_globals
elif hasattr(source, '__func__'):
func = source.__func__
name, ls, gs = func.__qualname__, (func.__closure__ or {}), func.__globals__
elif hasattr(source, '__init__'):
func = source.__init__.__func__
name, ls, gs = func.__qualname__, (func.__closure__ or {}), func.__globals__
else:
raise ValueError(f'Don\'t support source {source}')
ipython = [f for f in inspect.stack() if f.filename.startswith('<ipython-input')][-1].frame
ipython.f_locals.update({k: v for k, v in gs.items() if k[:2] != '__'})
ipython.f_locals.update({k: v for k, v in ls.items() if k[:2] != '__'})
# Magic call to make the updates to f_locals 'stick'.
# More info: https://pydev.blogspot.co.uk/2014/02/changing-locals-of-frame-frameflocals.html
ctypes.pythonapi.PyFrame_LocalsToFast(ctypes.py_object(ipython), ctypes.c_int(0))
message = 'Copied {}\'s variables to {}'.format(name, ipython.f_code.co_name)
raise RuntimeError(message)