I just learned about the Atom `markdown-table-calc`

package (or the corresponding vscode package) and thought, that this feature would definitely be a nice addition for Joplin, too. And now that I investigated into it, I saw that Evernote users want this, too. So I guess it'd also be a good 'selling point' for Joplin.

The implementation allowed to create a comment on the end of a markdown table and calculate things in the last row.

For instance:

```
| Column A | Column B | Column C |
|:---------|:---------|:---------|
| 123 | 456 | 789 |
| 0 | 0 | 0 |
| <!--f A1 * B1 -->56088 | <!--f B1 -->456 | <!--f SUM(C1:C2) -->789 |
```

It used `markdown-it`

and the mighty `formula-parser`

(although nowadays there's the package `hyperformula`

from the same folks, which claims to have "*a high-performance*").

## Usage

To define a set of table formulas, you can add a special HTML comment in a table cell.

```
| Column A | Column B | Column C |
|:---------|:---------|:---------|
| 123 | 456 | 789 |
| 0 | 0 | 0 |
| <!--f A1 * B1 -->56088 | <!--f B1 -->456 | <!--f SUM(C1:C2) -->789 |
```

Formulas are calculated in the order they are written. Table cells are described using spreadsheet notation, columns designated with letters like **A,B,C .. Z** (and even more AA, AB etc.) and rows with integers **1,2,3 ...** You can also use range notation like **A1:E23**. Moreover, hot-formula-parser contains also a big set of predefined functions which can be used in formulas.

You can find a corresponding GitHub issue 4072 and oswida's implementation at https://github.com/oswida/joplin-markdown-calc#joplin-markdown-table-calculations-plugin