lab 1 · first doc (Qmd) — source
A. Stamm 
This page shows the source file of the lab below. Use the button to download it as a plain file and run it in your own workspace.
---
title: "Lab 1: your first Quarto document"
subtitle: "Reproducible Workflows · Session 1"
author: "Your Name"
format: html
editor: source
---
> ~30 min. This is your first **reproducible** document: everything below is
> created from (and rendered by) source; nothing is copied by hand into the
> output. When you're done, ask a neighbour to *render your file on their
> machine* and confirm it produces the same result.
## Step 0: get a working document
1. Create a new Quarto document in Positron (`File → New File → Quarto Document`).
2. Render it (`Preview`) and confirm you see a small HTML report.
3. Open the source (`.qmd`) beside the preview. **Watch** the `.qmd` while you work.
## Step 1: prose
Replace the placeholder text with a short paragraph about yourself: a sentence
or two using a **heading**, a **bold/italic** word, and a **bullet list** of
three things you'd like to get better at in R. If you're new to Markdown, look
at how this lab file is written: headings are `##`, emphasis is `*…*` and
`**…**`, lists are `-`.
## Step 2: inline code
Write a sentence that uses **inline code** to state a number computed by R. The
line below does this for real (it evaluates when you render):
The sum of `r sum(1:10)` is the total of the first ten integers.
Edit the `1:10` and re-render; the number in the sentence *updates by itself*.
That's the pattern: a single backtick, the letter r, your expression, and a
closing backtick, evaluated on every render. (The line above shows it working;
open that line's source to see the exact syntax).
## Step 3: a code chunk and a figure
Add a code chunk that produces a simple plot. The chunk below loads the
**tidyverse** (silencing its startup messages with `#| message: false`) and
draws a `ggplot2` scatter plot of the built-in `iris` data:
```xkb
#| label: fig-scatter
#| fig-cap: "Sepal length vs. petal length in the iris data."
#| message: false
library(tidyverse)
ggplot(iris, aes(Sepal.Length, Petal.Length)) +
geom_point(colour = "#2E7D6B")
```
Re-render. Notice:
- the **code** *and* the **plot** both appear;
- the plot gets a **caption** (`fig-cap`) and a number;
- try adding `#| echo: false` above the chunk; now the plot appears *without* the code, like a real figure in a report.
## Step 4: a table
Add a chunk that computes a small summary table and prints it (the tidyverse
is already loaded from Step 3, so no library call is needed):
```xkb
#| label: tbl-summary
iris |>
group_by(Species) |>
summarise(mean_sepal = mean(Sepal.Length), .groups = "drop")
```
Now refer to that work in prose with a proper **caption**. Set a table caption
with `#| tbl-cap: "Mean sepal length by species."` just above the chunk.
## Step 5: a heading structure
Give your document a clear heading structure. A minimal report reads:
- `## The question`
- `## The data`
- `## Cleaning` (a note on what you decided and why)
- `## Results` (your figure and table live here)
- `## Findings`
## Done: check yourself
- Does the document **render** from scratch (`quarto render`, no manual steps)?
- Does the sentence with **inline code** stay correct when you change the input?
- Is every **figure** and **table** given a **caption**?
- Would a classmate, opening only your `.qmd` file, be able to reproduce your report?
> **Stretch.** Add a second figure using `ggplot2` (`#| message: false` to
> silence the package-load message) and a short paragraph that *refers to it in
> prose*: "Fig. 2 shows that…". Changing the figure's title to match.