Jupyter Notebook is an environment where you can write and run code. You can also include descriptive text (like what you’re reading right now!) to describe your code. Many researchers use it to write up their reports with embedded code examples that you can run and test for yourself. In the following lessons you will be using the Python programming language. However, Jupyter Notebook supports over 40 programming languages!

When you first open Jupyter, you will see a screen similar to the one below. It shows you a list of all your current notebooks. The picture shows the different parts of the home screen. To open a notebook, click on the name of the notebook you would like to open. The color of the notebook icon will indicate which notebooks are already open.

You write the code for your Zumi inside Jupyter Notebook. When you open a lesson, you should already see cells filled with text and code. To go through the lesson, you will need to run code, stop code, and save your changes! The most important tools that you will use are highlighted for you below:

A typical Jupyter notebook is divided into cells. Some cells have text, such as the one you are currently reading, and some cells can run code.

Running code

The cell below is an example of a code cell. To run the cell and execute code, select it so that it is highlighted in blue or green. For future reference, a cell outline in blue is selected but not in edit mode. A cell outlined is green is selected and in edit mode. In either state, you can click “Run” in the toolbar or press Shift + Enter.

In [ ]: print("This is a code cell!")

print("This is not a code cell")

Stopping the code

Sometimes you need to stop the code that is currently running. Maybe you have a while loop that is going forever and you are trying to escape! Next to the “Run” button in the toolbar you will find a black square. This is the stop button and will terminate the cell that is running. Run the cell below (which runs forever) and then stop the code.

count=0
while True:
    print(count)
    count+=1

Did you notice while the cell is running there’s an asterisk next to the cell? It looks like this: In[*]. Any cell with an asterisk is still running. Avoid trying to run more cells if one is still running.

In [ ]:

count=0
while True:
    print(count)
    count+=1

Adding cells¶

If you want to create a new cell, go to the toolbar and click “Insert”. In the menu you have options to insert a cell above or below the current cell.

Deleting cells¶

Under “Edit” in the toolbar, you will find many tools including “Delete Cells”. This will delete any cells that are currently selected.

Restarting a notebook¶

There may be times when you want to clear all of the output from your cells and restart all of your code. In the toolbar there is a tab called “Kernel”, and in its menu you will see an option to “Restart & Clear Output”. Once you select it, all of the output will be erased and those cells will be ready to be run again! You can double check by looking for empty In[] brackets.

Shutting down a Jupyter Notebook

Even if you close the tab, a notebook will remain open until shutdown. It is recommended you leave only one notebook open at a time. To shut down a notebook, select it and click on the orange “Shutdown” button. Be careful not to delete it by accident!