The following are some common issues and questions that have arisen whenbuilding your textbook with Jekyll.

How can I update my book?

Sometimes Jupyter Book will get updates that you want to incorporate intoa book you've already built. The easiest way to do this is to use the Command-Line Interface toupgrade your book.

To upgrade a pre-existing Jupyter Book, run the following command:

jupyter-book upgrade path/to/mybook

This will do the following:

• Generate a fresh Jupyter Book in mybook_UPGRADED using the content files in yourcurrent book.
• If this succeeds, copy over the contents of mybook_UPGRADED into your current book folder.
• If this succeeds, delete the mybook_UPGRADED folder. Note that only the content that you can manually specify via the jupyter-book create commandwill be retained in your upgraded book. For a list of these options, see the help menu for this command:

jupyter-book create -h

You should check out the content in your upgraded book to make sure it looks correct, thencommit the changes to your repository.

Does the book behave differently depending on the browser?

Maybe - Jupyter Book does use some features that might have different behaviors insome browsers. For example, Safari tends to treat downloadable objectsdifferently for some reason.

The two browsers on which Jupyter Book should always behave as expected areFirefox and Chrome.

Why isn't my math showing up properly?

This book uses MathJax to render all math, with $ denoting inline math,and $$ denoting multi-line math blocks. Make sure that all of your mathis wrapped in these characters.

Another tip is to remember to use escape characters when you don't wantmath to be rendered and instead want an actual dollar sign to show up.To do so, simply add a \ in front of the dollar sign. For example, Ican write \$35 by writing it like \\$35 in the markdown.

How can I include interactive Plotly figures?

To display interactive Plotly figures, they mustfirst be generated in a Jupyter notebook using the offline mode.You must then plot the figure with plotly.offline.plot(), which generates an HTML file (plotly.offline.iplot() does not),and then load the HTML into the notebook with display(HTML('file.html')) prior to saving your *.ipynb file.

e.g.

from IPython.core.display import display, HTML
from plotly.offline import init_notebook_mode, plot
init_notebook_mode(connected=True)
.
.
.
plot(fig, filename = 'figure.html')
display(HTML('figure.html')

Note that, if viewing the file on a Jupyter Notebook session, the figure will not be displayed there (iplot is needed for this). However, if working on a JupyterLab session, the figure can be displayed there using the plot code above by having the JupyterLab plotly extension installed.

What if I have an issue or question?

If you've got questions, concerns, or suggestions, please open an issue atat the jupyter book issues page

How should I add cell tags to my notebooks?

You can control the behavior of Jupyter Book by putting custom tagsin the metadata of your cells. This allows you to do things likeautomatically hide code cells as well asadding interactive widgets to cells.

There are two straightforward ways to add metadata to cells:

• Use the Jupyter Notebook cell tag editor. The Jupyter Notebook ships with acell tag editor by default. This lets you add cell tags to each cell quickly.

To enable the cell tag editor, go click View -> Cell Toolbar -> Tags. Thiswill enable the tags UI. Here's what the menu looks like.

• Use the JupyterLab Cell Tags plugin. JupyterLab is an IDE-like Jupyterenvironment that runs in your browser. It has a rich extension ecosystem.A particularly useful extensionis the "cell tags" plugin,which exposes a user interface that lets you quickly insert cell tags.

You can install the cell tags plugin with the following command (after installingJupyterLab).

jupyter labextension install @jupyterlab/celltags

Then, you'll find tags under the "wrench" menu section.Here's what the tags UI in JupyterLab looks like.

Why doesn't math show properly when printing?

Currently, we use a library called PrintJS to handleprinting of just the notebook content (when you click the "print -> PDF" buttons).

However, a drawback of this approach is that MathJax mathematics cannot access thesame fonts available when you're viewing a page live. This means that mathematics oftenlook simplified and incorrectly-formatted.

If you have an idea for how to improve this, pleaseopen an issue!

What is this Gemfile.lock file or why am I getting Jekyll dependency warnings?

The way that you define dependencies in the Ruby language is with a Gemfile. This islike a requirements.txt file in Python - it defines the packages needed to deploya web application (in this case, our Jupyter Book). When you build the book, a newfile will be created called Gemfile.lock. This freezes the dependency versions thatare specified in your Gemfile, which is useful for things like cacheing your buildsto make them faster.

However, sometimes you want to un-freeze your dependency versions, often becauseyou either wish to use new functionality in a package, or because you're gettinga warning that there is a vulnerability in an old version of a package.

To update your Gemfile packages, simply delete Gemfile.lock and re-run make install.This will generate a new Gemfile.lock with the latest versions of each packagespecified in your Gemfile (unless you have explicitly provided a version number there).

This page was created by The Jupyter Book Community