The Inline Python Code for Quarto is not working in VS Code but the Inline R Code is!

[victorvanpelt]

Description

Hello,

I am currently incredibly confused why my inline python code is not working, but my inline R code is working.

Here is my code:

This produces the following:

Does anyone know why my python inline code isn't working?

I have already checked whether Python executes. It does, but only within the python code block.

Thanks in advance!

[mcanouil]

The Python inline is for Jupyter (https://quarto.org/docs/computations/inline-code.html).

I don't think knitr/reticulate even supports Python inline or any knitr engine/language other than R.
Cc @cderv

[mcanouil]

So we could be changing {python} x to this in Quarto when inside knitr engine context.

You mean `{python} x` to `r py$x` (internally)?

[cderv]

yes - something like that, when we are sure that reticulate is available and loaded.

[cscheid]

@cderv Thanks for the correction! Is there a syntax that works for a more general expression? Say, {python} x * foo(3 + 4, bar = y + "blah")

[cderv]

For this, it would mean asking reticulate to execute the python code from R : https://rstudio.github.io/reticulate/articles/calling_python.html

There are several ways, one of them is to execute from a string - really dummy example

---
title: "A title"
---


```{r}
library(reticulate)
```

```{python}
x = 5
y = "boo"
## foo is a function that takes x and y and concatenating both returning a string
def foo(x, bar):
  return str(x) + "**" + str(bar) + "**" + " "
```

`r py_run_string('zz = x * foo(3 + 4, bar = y + "blah")'); py$zz`

Other way is to run from a file.

So we could do something more complex, like writing to temp file the code, running it with reticulate and loading the object.

I wonder if this should be something from reticulate itself instead of Quarto, through a more generic support in knitr

• inline code chunks for foreign engine yihui/knitr#2026

[cscheid]

Let's discuss this on Thursday.

[cderv]

I don't think knitr/reticulate even supports Python inline or any knitr engine/language other than R.

Let me be more precise on this affirmation.

knitr supports any language that has a knitr's engine defined. Built-in or coming from other R packages. More on this in knitr docs

• https://bookdown.org/yihui/rmarkdown/language-engines.html
• https://bookdown.org/yihui/rmarkdown-cookbook/other-languages.html
  Even a custom engine can be defined (https://bookdown.org/yihui/rmarkdown-cookbook/custom-engine.html)

python engine for knitr is from reticulate R package: https://rstudio.github.io/reticulate/reference/eng_python.html

Regarding inline execution, it is a knitr specific feature to the R engine - so only `r x` works (or `{r} x` in quarto - https://quarto.org/docs/computations/inline-code.html#syntax-compatibility) - at least for now yihui/knitr#2026

However, some packages like reticulate offers interoperatibility, and so Python values can be accessed from R. This means you just have to leverage the R inline syntax. See https://rstudio.github.io/reticulate/articles/r_markdown.html

---
title: test
---

```{r}
library(reticulate)
```


```{python}
a = 5
```

The variable is `r py$a`

```{r}
b = 5
```

The variable is `r b`

I hope this helps understand how it works.

[mcanouil]

I knew, there was a trick! Thanks Christophe!

[victorvanpelt]

Thanks a lot for explaining!