Using ggplot2 in IJulia notebook through RCall

RCall_IJulia_ggplot2.qmd

---
jupyter: julia-1.7
---

```{julia}
using RCall
```

```{julia}
RCall.ijulia_setdevice(MIME("image/svg+xml"))
```

```{julia}
R"""
#| label: fig-mpghwydispl
#| fig-cap: Highway gas mileage versus engine displacement by vehicle class
library(ggplot2)
ggplot(mpg, aes(displ, hwy, color = class)) + geom_point()
"""
```

RCall_IJulia_qqplot2_2.qmd

---
jupyter: julia-1.7  
format:
  html:
    code-fold: true
---

Load [RCall.jl](https://github.com/JuliaInterop/RCall.jl) and set the R graphics device output to SVG (Scalable Vector Graphics).

```{julia}
using RCall
RCall.ijulia_setdevice(MIME("image/svg+xml"));
```

As seen in @fig-mpghwydispl, cars with engines of lower displacement tend to have better gas mileage.

```{julia}
#| label: fig-mpghwydispl
#| fig-cap: Highway gas mileage versus engine displacement by vehicle class
R"""
library(ggplot2)
print(ggplot(mpg, aes(displ, hwy, color=class)) + geom_point())
""";
```

By explicitly `print`ing the plot in R and suppressing the output printing in Julia (the semicolon after the `@R_str` macro call) the plot and caption are displayed as desired.