Computational Environment Example 4

Orienting you to the GitHub repository

There are lots of links here, they're here to help understand the different branches in GitHub.

If you already know this, then feel free to jump to the instructions below.

There are three branches in this repository.

• master : https://github.com/alan-turing-institute/CompEnv-Ex4/tree/master
• branch-a : https://github.com/alan-turing-institute/CompEnv-Ex4/tree/branch-a
• branch-b : https://github.com/alan-turing-institute/CompEnv-Ex4/tree/branch-b

There's an identical analysis.R file in all three branches.

• analysis.R in master : https://github.com/alan-turing-institute/CompEnv-Ex4/blob/master/analysis.R
• analysis.R in branch-a : https://github.com/alan-turing-institute/CompEnv-Ex4/blob/branch-a/analysis.R
• analysis.R in branch-b : https://github.com/alan-turing-institute/CompEnv-Ex4/blob/branch-b/analysis.R

There's an identical CompEnv-Ex4.Rproj file in all three branches.

• CompEnv-Ex4.Rproj in master : https://github.com/alan-turing-institute/CompEnv-Ex4/blob/master/CompEnv-Ex4.Rproj
• CompEnv-Ex4.Rproj in branch-a : https://github.com/alan-turing-institute/CompEnv-Ex4/blob/branch-a/CompEnv-Ex4.Rproj
• CompEnv-Ex4.Rproj in branch-b : https://github.com/alan-turing-institute/CompEnv-Ex4/blob/branch-b/CompEnv-Ex4.Rproj

Two of the branches have files that capture the computational environment:

• master does not contain files to capture the computational environment.
• branch-a has two files to capture the computational environment: https://github.com/alan-turing-institute/CompEnv-Ex4/blob/branch-a/install.R and https://github.com/alan-turing-institute/CompEnv-Ex4/blob/branch-a/runtime.txt
• branch-b has two files to capture the computational environment: https://github.com/alan-turing-institute/CompEnv-Ex4/blob/branch-b/install.R and https://github.com/alan-turing-institute/CompEnv-Ex4/blob/branch-b/runtime.txt

Instructions

1. Click the links below to open the Binders for branch-a and branch-b. These will take you to RStudio. We recommend you right click and select "Open Link in a New Tab" in order to keep these instructions visible.

• 👉 Binder for branch-a: https://mybinder.org/v2/gh/alan-turing-institute/CompEnv-Ex4/branch-a?urlpath=rstudio

• 👉 Binder for branch-b: https://mybinder.org/v2/gh/alan-turing-institute/CompEnv-Ex4/branch-b?urlpath=rstudio

  RStudio is an IDE (integrated development environment). It has 3 windows

  • On the left is the R Console where R commands can be executed interactively.
  • On the upper right is a window which shows the variables saved in the environment after code is executed (among other things).
  • And on the lower right is a file structure window.

2. Open the analysis.R file by clicking on it in the bottom right window.

   This will open a new window in the upper left, above the R console, containing the code.

3. With your cursor, highlight the all of the code in the new window. Run the code by clicking the "Run" button at the top of this window.

Questions

• What's different between these two branches?
• What is the difference in the output?
• How do these differences arise?