Demo r nvim plugin

r-nvim-demo.qmd

---
title: "R.nvim Feature Demo"
format: html
---

## Getting Started with R.nvim

R.nvim is a Neovim plugin for R development. Open this file in Neovim and
follow along to explore its features.

### Starting R

Press `\rf` to start R in a split terminal. R.nvim will open an R console
beside your editor. Other start commands:

- `\rf` — Start R (default)
- `\rq` — Quit R
- `\rl` — List the R workspace (`ls()`)
- `\rc` — Clear the R console

## Executing Code

### Send a single line

Place your cursor on any line below and press `\l` to send it to R:

```{r}
x <- seq(1, 100)
y <- x^2 + rnorm(100, sd = 200)
message("x and y are now defined")
```

### Send a selection

In visual mode, select lines and press `\ss` to send the selection.

### Send an entire code block

Place your cursor inside the block below and press `\cc` to send the whole
chunk to R:

```{r}
library(datasets)

# Basic arithmetic
a <- 10
b <- 25
result <- a * b + sqrt(b)
print(paste("Result:", result))
```

### Send from the cursor to the end of the block

Press `\cd` to send from the current line to the end of the chunk.

```{r}
nums <- c(3, 7, 2, 9, 4, 6, 1, 8, 5)
sorted <- sort(nums)
print(sorted)
cat("Mean:", mean(nums), "\n")
cat("SD:", sd(nums), "\n")
```

## Plotting

R.nvim can display plots in a separate graphics window. Send the chunks below
with `\cd` to see plots rendered.

### Base R plot

```{r}
#| label: fig-scatter
#| fig-cap: "Scatter plot with trend line"

plot(x, y,
     main = "Quadratic Relationship with Noise",
     xlab = "x",
     ylab = "y",
     pch = 19,
     col = rgb(0.2, 0.4, 0.8, 0.6))
abline(lm(y ~ x), col = "red", lwd = 2)
```

### ggplot2

```{r}
#| label: fig-ggplot
#| fig-cap: "Distribution of diamond prices"

library(ggplot2)

ggplot(diamonds[sample(nrow(diamonds), 2000), ], aes(x = carat, y = price)) +
  geom_point(aes(color = cut), alpha = 0.6) +
  geom_smooth(method = "loess", se = TRUE) +
  scale_color_viridis_d() +
  labs(title = "Diamond Price vs Carat",
       x = "Carat",
       y = "Price (USD)") +
  theme_minimal()
```

### Histogram

```{r}
#| label: fig-hist
#| fig-cap: "Distribution of residuals"

residuals <- y - predict(lm(y ~ x))
hist(residuals,
     breaks = 20,
     col = "steelblue",
     border = "white",
     main = "Residuals from Linear Fit",
     xlab = "Residual Value")
```

## Viewing Dataframes

R.nvim provides built-in dataframe viewing. Place your cursor on a dataframe
name and press `\rv` to view it in a tab. Navitage tabs with gt and gT. 
:tabclose to close it.

### Create and inspect a dataframe

```{r}
df <- data.frame(
  id = 1:20,
  name = paste0("subject_", sprintf("%02d", 1:20)),
  group = rep(c("control", "treatment"), each = 10),
  score = c(rnorm(10, mean = 50, sd = 10),
            rnorm(10, mean = 58, sd = 10)),
  passed = sample(c(TRUE, FALSE), 20, replace = TRUE, prob = c(0.7, 0.3))
)
```

Now try these R.nvim object inspection shortcuts:

- `\rv` — View the dataframe (opens in a buffer via `head()`)
- `\vs` — Print `summary(df)` in the R console
- `\rh` — Show help for the object under cursor

```{r}
# Cursor on 'df' and press \rv to view it
df

# Explore structure
str(df)
summary(df)
```

### Working with built-in datasets

```{r}
# View the mtcars dataset — place cursor on mtcars and press \rv
data(mtcars)
head(mtcars)
```

```{r}
# Grouped summary
aggregate(mpg ~ cyl, data = mtcars, FUN = mean)
```

## Object Browser

Press `\ro` to open the Object Browser. It shows all objects in your R
environment organized by type. You can expand lists and dataframes to see
their structure.

```{r}
# Create some objects to see in the browser
my_list <- list(
  numbers = 1:5,
  text = c("hello", "world"),
  nested = list(a = TRUE, b = 3.14)
)

my_matrix <- matrix(1:12, nrow = 3, ncol = 4)
my_factor <- factor(c("low", "med", "high", "low", "high"))
```

## Useful Keybinding Summary

| Keybinding | Action                          |
|------------|---------------------------------|
| `\rf`      | Start R                         |
| `\rq`      | Quit R                          |
| `\l`       | Send current line               |
| `\ss`      | Send selection (visual mode)    |
| `\cc`      | Send current code block         |
| `\bd`      | Send block from cursor downward |
| `\rv`      | View object under cursor        |
| `\vs`      | Summary of object               |
| `\rh`      | Help on object                  |
| `\ro`      | Toggle Object Browser           |
| `\rl`      | List workspace                  |
| `\rc`      | Clear console                   |
| `\gn`      | Jump to next code chunk         |
| `\gN`      | Jump to previous code chunk     |
| `gt`       | Switch tabs                     |
:tabclose