In Jupyter notebook, if I have
print("hello") quit() in the first cell and
print("Good bye") in the second, when I do "Run all" it prints hello and also Good bye.
In other words, quit() seems to only stop the execution of the cell itself, not the whole script.
Is there some way to add a breakpoint to your code so that it stops executing when it gets to it?
You can use IPython.core.debugger.Pdb to invoke pdb. Insert the following line to set a breakpoint.
from IPython.core.debugger import Pdb; Pdb().set_trace() See this page for debugger commands.
Also, you can use %debug magic to invoke pdb after an error. Just type %debug to the next cell if an exception occurs. Then pdb runs from its stack frames.
From the JupyterLab docs:
JupyterLab 3.0 now ships with a Debugger front-end by default.
For the debugger to be enabled and visible, a kernel with support for debugging is required.
If you are using Pip, install the Xeus-Python kernel with pip install xeus-python.
Then open a jupyterlab notebook, and choose the new kernel from the toolbar:
You can then debug your code as follows:
Source: https://jupyterlab.readthedocs.io/en/stable/user/debugger.html
xeus-python is also available in Conda. Try: conda install -c conda-forge xeus-python
As far as I know, jupyter notebook doesn't have a breakpoint function however you can add something like:
assert False, "breakpoint" where you want to stop although it isn't very elegant.
Jupyter Notebook has visual debugger just like Jupyter Lab since version 7.0.0, released in July 2023. You can use it exactly like abrac showed in his answer. Just make sure that you enabled the debugger by clicking on the small bug icon on top right corner and optionally display the debugger panel (with Ctrl + Shift + E shortcut or using top bar: View > Debugger Panel).
You can probably try exit() but I am not sure if that's exactly what you need.
quit() as far as I can tell. In other words it doesn't stop the rest of the script from running.