In 2DegreesInvesting/ds-targets: What the Package Does (One Line, Title Case)

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A series of meetups about data pipelines with the package "targets".

Syllabus

Except for the first one, each item in this syllabus corresponds to a meetup and a GitHub release that preserves a snapshot of this repository exactly as it was shown during thee meetup.

We'll follow targets' manual but loosely.

Motivation

Meet Will Landau.

Walkthrough

Setup a minimal targets project from scratch.

Objectives:

• Setup a file "_targets.R" and explore its structure.

• Try common functions:

  • tar_script().
  • tar_edit().
  • tar_glimpse().
  • tar_make().
  • tar_visnetwork().
  • tar_objects().
  • tar_read().

• Create a report using targets.

• Understand the benefit.

Functions

This meetup adapts the examples shown in the "Functions" chapter of targets manual. It covers how to refactor a data science project, moving from a workflow based on a sequence of scripts to a workflow based on a pipeline of functions.

Objectives:

• Explore an analysis structured as a sequence of scripts.

• Make and use our own targets.

• Report multiple analyses with the same superset of targets.

• Transform code chunks into functions.

• Report the analysis as using targets.

• Make and use targets from the package targets.

Target cues

This meetup covers the rules that mark a target as outdated. It explores the helpfile of tar_cue(). After this session you will be more able to predict when tar_make() will either skip or run a target, and to set the options that trigger the behavior you want.

Objective:

• Understand the details of tar_cue().

Best practices

This meetup covers selected topics from the chapter Best Practices of target's manual.

Objectives:

• Understand how to define good targets.

• Understand how to ignore or depend on changes in R packages.

External files and literate programming

This meetup covers selected topics from the chapter External files and literate programming of targets's manual.

Objectives:

• Understand what it means for a file to be external.

• Understand how to use external files as inputs and outputs.

• Use a superset of targets in a subset of workflows (rmarkdown files).

• Use a targets factory to render rmarkdown reports inside the targets pipeline.

Debugging

This meetup covers the chapter Debugging of targets's manual.

Objectives:

• Understand three approaches to debugging, which the manual refers to as:
  • environment browser,
  • the debug option,
  • workspaces.

Next

We could cover branching (dynamic and static) and targets factories, but this might also be a good stopping point.

Resources

• Repo: https://github.com/2DegreesInvesting/ds-targets

• Will's bio: https://wlandau.github.io/about.html

• 10’ intro: https://youtu.be/GRqKJBaC5g4

• Website: https://docs.ropensci.org/targets/

• 1/2 day tutorial: https://github.com/wlandau/targets-tutorial

• Manual: https://books.ropensci.org/targets/

• R packages, particularly The whole game and The package within

• Targetopia.

2DegreesInvesting/ds-targets documentation built on March 19, 2021, 9:45 a.m.