Markdown

@-mentions

See @Mention collaborators in chat.

Checkboxes

Type “ [ ] “ to create an unchecked checkbox. Note the single space between the square brackets. Type “ [x] “ to create a checked box. In both unchecked and checked boxes, there is a space before the first bracket and a space after the closed bracket.

Collaborative editing

Multiple users can edit CoCalc Markdown at the same time. In fact, one user can have several browser windows open to the same Markdown content and edit from them all simultaneously (we sometimes use this feature to test collaboration while developing CoCalc).

Details element

CoCalc markdown editing supports The Details disclosure element. Here is how a details element is entered, using Markdown code edit mode:

<details>
    <summary>summary text</summary>
    Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua...
</details>

You can put text that you want hidden inside the details element. When not expanded, only the summary text is displayed. To expand the content and show the hidden content, click anywhere in the summary. To hide the content, click the summary again. If you do not specify summary text, the word “Details” is used.

Embedded LaTeX

You can write LaTeX formulas between $ signs, e.g. $\frac{1}{1+x^2}$.

Emojis

View the list of supported emojis in the markdown-it-emojis GitHub repository.

Export to HTML

• To create html from a markdown file, open a Linux terminal. If your file is “filename.md”, run the command:

  pandoc filename.md -o filename.html
  

Export to PDF

• To export a markdown (“.md”) file as pdf, open the file, select “Locked” from the view pulldown menu and click the “Print” button.

Fenced Code Blocks

Code in fenced code blocks can be executed using any available jupyter kernel. In the example, the “Python 3 (system wide)” kernel is active. Hover your cursor over the kernel selector to expose a menu for selecting other kernels. Click “Run” to produce the output. Hover over the space below the output to get buttons for additional code cells. This feature even works if the document is published.

The info string should start with the programming language want to use, for example “python”, “sage”, “bash”, or “julia”. Typing in the language will select one possible kernel. Use the Jupyter kernel selector if you would like a different kernel for the selected language.

You can append descriptive text to the info string, such as “ex 1”.

If you evaluate a cell, everything above it with the exact same info string is always run. Clicking “Run” in the third cell in the following example will cause the first cell to be run before it, but not the second cell.

Hashtags

Precede a word with a hash sign (“#”) and it is formatted to stand out as a hashtag.

Inverse search

The markdown editor supports inverse search when source and rendered views are both visible (this is the default display for markdown files). If you double-click on markdown in the rendered view, the source view will scroll to display the corresponding line.

If you are using a split view with Markdown Code in one pane and Editable Text in the other, you can use the sync button: at the top from either pane to synchronize the cursor in the other pane.

See Rich Text Editing.

Quarto

You can work with Quarto documents by creating a file with .qmd extension. Use jupyter: sage-10.3 or similar kernel selection if you want to use SageMath code blocks, which should be marked with {sagemath}

---
jupyter: sage-10.3
---
```{sagemath}
factor(2024)
```

Reference links

CoCalc will gather hyperlinks in a References section at the bottom of the file if you use either of the following formats to enter hyperlinks while in Markdown code edit mode. The input format for reference links follows the specification here, markdown reference links (with the enhancement that with implicit link names, an empty pair of brackets is not needed).

Implicit link name. In the body of your document, enclose the text reference to the link in square brackets. Then include a definition of the link on a separate line. You may append an optional title string, surrounded by single or double quotes, to the definition. The definition does not have to be next to the reference; for example, you could gather definitions at the bottom of your document. Here is an example of a link reference line and a corresponding definition line:

Here is some text with a link to [CoCalc]

[CoCalc]: https://cocalc.com 'optional added text'

Link id. Here’s another example of a link reference line followed by the corresponding definition. In this case the link id is numeric:

Use [Sagemath][1] for numeric and symbolic mathematics.

[1]: https://sagemath.com 'sagemath site'

CoCalc will create the following References section at the bottom of the markdown file from the sample links above.

Rich Text Editing

See Rich Text Editing.