Lesson 2 — Installing R & RStudio, and Using CSUB JupyterHub

1Objectives¶

By the end of this lesson you will be able to:

1. Decide, for your own situation, whether to install R/RStudio or use CSUB JupyterHub.

2. Install R and RStudio Desktop on a Windows or Mac computer.

3. Open CSUB JupyterHub and start an R notebook without installing anything.

4. Confirm that your setup is actually working.

2Two ways to get R — pick one¶

You do not need both. Pick whichever fits you; you can always switch later, since the R underneath is identical either way (Lesson 1).

3Option A — Install R and RStudio on your own computer¶

You need two separate downloads, installed in this order: R first, then RStudio. RStudio is just the friendly window (Lesson 1); it needs R already present to have an engine to run.

3.1Step 1 — Install R¶

1. Go to cran.r-project.org (CRAN — the official home of R).

2. Click the download link for your operating system:

   • Windows: “Download R for Windows” → “base” → the big Download R link.

   • Mac: “Download R for macOS” → the .pkg file matching your Mac (Apple silicon vs. Intel — if you’re not sure which chip your Mac has, choose the arm64 build for anything from late 2020 onward, or check Apple menu ▸ About This Mac).

3. Open the downloaded file and click through the installer with the default options — you don’t need to change anything.

3.2Step 2 — Install RStudio Desktop¶

1. Go to posit.co/download/rstudio-desktop (RStudio is made by a company called Posit).

2. Download the free RStudio Desktop installer for your operating system.

3. Run the installer with the default options.

3.3Step 3 — Open RStudio and confirm it worked¶

Open RStudio (not R by itself — you’ll always open RStudio, and it starts R for you automatically). You’ll see a window divided into a few panes; Lesson 3 tours them properly. For now, click inside the pane titled Console (it should already be active) and type this, then press Enter:

R.version.string

[1] "R version 4.5.2 (2025-10-31 ucrt)"

Your version number and date will likely differ from the one shown above (new R versions come out a few times a year) — that’s completely fine. What matters is that you see some version string print back, which means R is installed and RStudio can talk to it.

4Option B — Use the CSUB JupyterHub (no installation)¶

CSUB provides a shared JupyterHub server where R already has the whole course toolkit (Lesson 5) pre-installed — you log in through a browser and get a notebook, a document that mixes your own notes with runnable R code (more on notebooks in Lesson 3).

1. Go to https://csub.jupyter.cal-icor.org/. That is CSUB’s JupyterHub for this course; mosaic and BSDA are already installed there for you. (Your instructor or the course Canvas page may also give you a link that pre-loads a specific lab.)

2. Log in with your CSUB credentials (the same ones you use for Canvas/MyCSUB).

3. You’ll land on a file browser. Your instructor will tell you whether to open a notebook they’ve already shared with you, or to create a new one: New ▸ Notebook ▸ R.

4. In the first gray box (a cell), type a line of R and run it with Shift + Enter (this runs the cell and moves you to the next one).

There is nothing to install, nothing to update, and your work is saved on CSUB’s server — handy if you switch between the campus computer lab and your own laptop.

5Which one should you actually use?¶

If you’re not sure, start with CSUB JupyterHub — it has zero setup, so you can be running R in the next five minutes and worry about installing anything later (or never, if JupyterHub works fine for you all semester).

6Troubleshooting a stuck install¶

• Windows says it can’t run the installer / “protected your PC.” Click More info, then Run anyway — this is a standard Windows warning for any new installer, not a sign of a problem.

• Mac says the app is from an “unidentified developer.” Right-click (or Control-click) the installer and choose Open, then confirm.

• RStudio opens but the Console shows an error about R not being found. R didn’t finish installing, or RStudio was installed first. Reinstall R (Step 1), then reopen RStudio.

• You’re not sure JupyterHub logged you in correctly. Log out and back in with your full CSUB email/username, the same one you use for Canvas.

A full table of error messages and fixes is in Lesson 12.

7Summary¶

• You need R installed before RStudio, if installing locally: R first, then RStudio Desktop, both free from CRAN and Posit.

• CSUB JupyterHub needs no installation at all — just a browser and a link from your instructor.

• R.version.string (or the shorter getRversion()) is a one-line way to confirm R is alive and talking to you, in either setup.

8Check your understanding¶

1. Which install option makes more sense for your own situation, and why?

2. What is the correct order to install R and RStudio, and why does the order matter?

3. If a classmate’s R.version.string prints a different version number than yours, should you be worried? Why or why not?