freezr: A simple, transparent reproducibility tool

If you are a data analyst in a scientific or scholarly field, then you've likely experienced the tension between reproducibility demands and fast-changing custom analysis scripts. freezr is an R package meant to alleviate this tension. It helps you archive your current analysis in a snap so you can move on to the next question or approach. In a single line of code, it will helpfully:

• run your script,
• gather the output into a time-stamped results folder,
• save a copy of your code, repo hash, and sessionInfo() along with the results, and
• nag you to write down some notes about what you did.

For bigger projects, freezr includes a simple "inventory" system to keep track of saved data. This allows you to load data into a downstream script without hard-coding paths, which is particularly useful when saving intermediates inside of timestamped freezr archives.

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Getting started

You can install freezr using the devtools package:

install.packages("devtools") # installs devtools
devtools::install_github("ekernf01/freezr") # installs freezr

Then you can start freezing code immediately. The following line will run my_functions.R and then my_script.R, saving them and their results to ~/my_project/results/<timestamp>.

library(freezr)
freezr::freeze( analyses_to_run = c( "my_functions.R", "my_script.R" ),
                destination = file.path( "~", "my_project", "results" ) )

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Features

• The freeze function offers:

  • easy customization: if you want to save your own plots, your scripts can access the user subfolder of the freezr archive via Sys.getenv()[["FREEZR_DESTINATION"]].
  • dependency tracking: freezr is not limited to saving code. You can also save tables or other files that your analysis depends on.
  • R markdown support: freezr can purl an R Markdown file and run the resulting R code.
  • Graphical and plain-text console output: freezr logs all output to files for you to peruse later.
  • Logs of your sessionInfo as well as the commit your repo is on. You can tell it to track other repos, too, if there is a package you are developing in a separate repo alongside your analysis repo.

• The inventory_* functions help you follow data from one analysis to the next. Use them to retrieve files without hard-coding a bunch of paths into your scripts. See ?freezr::inventory_make, ?freezr::inventory_add, ?freezr::inventory_get. These are most useful to me on larger projects, especially projects where my scripts save Seurat objects of size 1GB+ that are excluded from my git repo.

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Other reproducibility tools

I recently found out about recordr, which is very similar to freezr. I haven't tried recordr yet, but I know it is quite sophisticated and has some great interactive features. As far as I can see, the only functionality unique to freezr is the "inventory" system, which helps pass data between scripts. Here are some other tools relating to reproducible research in R. These solve problems that overlap with the domain of freezr, but none has the same purpose or functionality.

• To deal with statistical issues such as the "Garden of forking paths", there's revisit.
• The R Markdown and knitr family allow for readable documents with embedded source code.
• There are several systems to keep track of R package versions (PackRat, checkpoint, pkgsnap).

One inevitable question people ask is why we can't just use Git. Here's why I view Git as complementary to freezr, rather than capable of replacing freezr.

• freezr lets you run the analysis and archive it, both with a single command. This is easier than constantly forcing yourself to alternate between interacting with data and taking notes/making commits.
• freezr makes it easy to run and archive multiple analyses simultaneously. You can view old and new material together, with no need to switch branches or go back to previous commits.
• freezr is tailored to R, saving information on language and package versions that does not usually live inside a repo (unless you use PackRat or similar).
• freezr is easy to learn.

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FAQ

• I'm new to R. How do I access the help/manual page for your package?

Type ?freezr::freeze (core functionality) or ?freezr::inventory_add (extra tools for bigger projects).

• You broke my R console!

I'm sorry! This happens when freezr calls sink() and gets interrupted before it can clean up after itself. Try running freezr::sink_reset().

• What's next?

I'm working on a vignette and on linking freezr archives to the commit on which they were built.

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Citation

freezr is not published in any academic-style manuscripts. If freezr helped you in your work, you can refer to this repository, https://github.com/ekernf01/freezr .