This notebook gives some hints about what you can do if your notebook or a code cell does not react as expected, or you think something isn't working in your Jupyter Notebook.
You will learn about:
It may happen that you execute a cell (with Ctrl + ENTER
) and you do not see an output straight away. This can mean that your code is still processing. Wait a few minutes as some code blocks, especially those creating an animation or drawing a figure, can take a while to run. To see the status of your code cell you can check the [ ]
on it's left side. A code cell can have the following status:
[ ]
) being empty.# This is a non-executed cell
[1]
. The number shows the sequence in which the cell was executed.# This is an executed cell
[*]
). Additionally, during a cell execution, the circle on the top right of a notebook is coloured in grey (see image below).Sometimes, it may happen that the notebook's processing kernel dies. This can happen if you worked a long time on the notebook without refreshing it. If you execute a cell and nothing happens and you can see that the cell is no longer in processing mode, then it is recommended to restart the processing kernel. You restart the kernel of your notebook by either clicking on the circled arrow in the notebooks menu (see Figure below).
Alternatively, you can go to the JupyterLab menu and under the menu item Kernel
you find different options to shut down or restart a notebook's processing kernel.
A JupyterLab environment is similar to a workstation or your personal computer. If you end up having too many programs and browser tabs open, the reaction time slows down. In a JupyterLab interface, it easily happens to open many tabs (notebooks) at once and for each notebook, a distinct processing kernel is started. Hence, every now and then, it is recommended to clean your working environment, close open notebooks and shut down kernels you do not need at the moment.
On the left side bar of the JupyterLab interface, the menu has a square in a circle
as second tab. If you go to this tab, you get an overview of notebooks currently open as well as kernels currently active. There, you can manage your environment, close notebooks or shut down kernels (see Figure below). You can close notebooks and kernels individually or all at once. Please note that if you close a notebook, the kernel does not shut down automatically.
This project is licensed under GNU General Public License v3.0 only and is developed under a Copernicus contract.