JupyterLab Interface

For this course, your docker container has been configured to run Jupyter notebooks. When you go to the IP that the docker container prints out, you will see the JupyterLab interface.

The JupyterLab Interface is a dashboard that provides access to interactive Jupyter notebooks, as well as a terminal window into the Ubuntu operating system. The first view you'll see includes a menu bar at the top, a directory tree in the left sidebar, and a main work area that is initially open to the "Launcher" page.

Screenshot of the JupyterLab interfece with important sections pointed out.

Complete details for all the features and menu actions available can be found in the JupyterLab Interface document. Here are some key capabilities that will be especially useful in this course:

File browser:

The file browser in the left sidebar allows navigation through the Docker container file structure. Double-clicking on a notebook or file opens it in the main work area.

Jupyter notebooks:

The interactive notebooks used in this course have an ".ipynb" file extension. When a notebook is double-clicked from the file browser, it will open in the main work area and its process will start. The notebooks consist of text and code "cells". When a code cell is "run", by clicking the run button at the top of the notebook or the keyboard shortcut [CTRL][ENTER], the block of code in the cell is executed and the output, if there is any, appears below the cell in the notebook. To the left of each executable cell there is an "execution count" or "prompt number" in brackets. If the cell takes more than a few seconds to run, you will see an asterisk mark there, indicating that the cell has not finished its execution. Once processing of that cell is finished, a number will show in the brackets.

Screenshot of the JupyterLab interfece with important sections related to running pointed out.

Kernel operations:

The kernel for each running notebook is a separate process that runs the user code. The kernel starts automatically when the notebook is opened from the file browser. The kernel menu on the main menu bar includes commands to shutdown or restart the kernel, which you will need to use periodically. After a kernel shutdown, no code cells can be executed. When a kernel is restarted, all memory is lost regarding imported packages, variable assignments, and so on.

A gif demonstrating how to shut down the kernal.

Cell tabs:

You can move any cell to new window tabs in the main work area by right-clicking the cell and selecting "Create New View for Output". This way, you can continue to scroll down the JupyterLab notebook while still watching a particular cell. This is especially helpful in the cell includes a camera view!

A gif demonstrating how to create a terminal in Jupyter Notebook.

Terminal window:

You can work directly in a Terminal window on your Docker container OS. From the Launcher page, click the Terminal icon under "Other". To bring up the Launcher page, if it is no longer visible, click the "+" icon at the top of the left sidebar.

A gif demonstrating how to open a widget.