---
title: Mathematica
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---

import current from '/version.js';
import CodeBlock from '@theme/CodeBlock';

:::note

This demo was last tested in 2023 April 22 in Mathematica 13.2.1

:::

[The "NodeJS" instructions](/docs/getting-started/installation/frameworks)
describe installation steps for NodeJS projects.  Mathematica has built-in
features for external scripting with NodeJS. Helper functions can translate
between CSV text and Mathematica datasets or arrays.

Mathematica can also use [command-line tools](/docs/demos/desktop/cli)

## Integration Details

:::caution

Mathematica includes `ExternalEvaluate` for running scripts in an external
engine.  In local testing, there were incompatibilities with recent NodeJS
versions.  This demo uses the shell integration to call a command-line tool.

:::

### Command-Line Tools

`ExternalEvaluate` can run command-line tools and capture standard output:

```mathematica
cmd = "/usr/local/bin/xlsx-cli ~/Downloads/pres.numbers"
csvdata = ExternalEvaluate["Shell" -> "StandardOutput", cmd];
```

Once evaluated, `ImportString` can interpret the data as a dataset.  Typically
the first row of the CSV output is the header row.  The `HeaderLines` option
controls how Mathematica parses the data:

```mathematica
data = ImportString[csvdata, "Dataset", "HeaderLines" -> 1]
```

## Complete Demo

:::note

This demo was tested in macOS.  The path names will differ in other platforms.

:::

1) Create the standalone `xlsx-cli` binary:

<CodeBlock language="bash">{`\
cd /tmp
npm i --save https://cdn.sheetjs.com/xlsx-${current}/xlsx-${current}.tgz exit-on-epipe commander@2
curl -LO https://docs.sheetjs.com/cli/xlsx-cli.js
npx nexe -t 14.15.3 xlsx-cli.js`}
</CodeBlock>

This is discussed in ["Command-line Tools"](/docs/demos/desktop/cli)

2) Move the generated `xlsx-cli` to a fixed location in `/usr/local/bin`:

```bash
mkdir -p /usr/local/bin
mv xlsx-cli /usr/local/bin/
```

### Reading a Local File

3) In a new Mathematica notebook, run the following snippet:

```mathematica
SheetJSImportFile[x_] := ImportString[Block[{Print}, ExternalEvaluate[
  "Shell" -> "StandardOutput",
  "/usr/local/bin/xlsx-cli " <> x
]], "Dataset", "HeaderLines" -> 1]
```

4) Download <https://sheetjs.com/pres.numbers> and save to Downloads folder.

5) In the Mathematica notebook, run the new function. If the file was saved to
the Downloads folder, the path will be `"~/Downloads/pres.numbers"` in macOS:

```mathematica
data = SheetJSImportFile["~/Downloads/pres.numbers"]
```

The result should be displayed in a concise table.

### Reading from a URL

`FetchURL` downloads a file from a specified URL. This function will be wrapped
in a new function called `SheetJSImportURL`.

6) In the same notebook, run the following:

```mathematica
Needs["Utilities`URLTools`"];
SheetJSImportURL[x_] := Module[{path},(
  path = FetchURL["https://sheetjs.com/pres.numbers"];
  SheetJSImportFile[path]
)];
```

7) Test by downloading the test file in the notebook:

```mathematica
data = SheetJSImportURL["https://sheetjs.com/pres.numbers"]
```