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YOUR R LEARNING PATH

A little more R.
A little more confidence.

One idea at a time, with examples you can follow and checkpoints to see what’s clicking. New here? Begin with chapter one. Know a little already? Jump right in.

Before you start

Basic arithmetic and an interest in tabular data are useful. Start with vectors before missing values, data frames, and grouped calculations.

Review a foundation whenever you need it: First Python program

Start chapter one Ready for the final?
13 open chapters. Your progress is saved as you go.

Your chapters

Choose any starting point
  1. 01

    Vectors and elementwise arithmetic

    Beginner

    Treat vectors as the basic unit of an R calculation.

    Start here, or skip ahead
    Open chapter: Vectors and elementwise arithmetic
  2. 02

    Coercion and recycling contracts

    Beginner

    Check type and length before applying vector arithmetic.

    Open whenever you’re ready
    Open chapter: Coercion and recycling contracts
  3. 03

    Indexing and missing values

    Beginner

    Select vector elements while handling unknown data explicitly.

    Open whenever you’re ready
    Open chapter: Indexing and missing values
  4. 04

    Categories and level semantics

    Intermediate

    Treat categories as labels with a deliberate level set.

    Open whenever you’re ready
    Open chapter: Categories and level semantics
  5. 05

    Data frames and column structure

    Intermediate

    Preserve rectangular data and its intended column types.

    Open whenever you’re ready
    Open chapter: Data frames and column structure
  6. 06

    Matrix shape and margin operations

    Intermediate

    Align row and column operations explicitly.

    Open whenever you’re ready
    Open chapter: Matrix shape and margin operations
  7. 07

    Functions and controlled iteration

    Intermediate

    Write reusable functions with clear scalar decisions and empty-input behavior.

    Open whenever you’re ready
    Open chapter: Functions and controlled iteration
  8. 08

    Lists and predictable transformations

    Advanced

    Transform heterogeneous structures without surprising output shapes.

    Open whenever you’re ready
    Open chapter: Lists and predictable transformations
  9. 09

    Keyed alignment and join cardinality

    Intermediate

    Align records by keys rather than by incidental row positions.

    Open whenever you’re ready
    Open chapter: Keyed alignment and join cardinality
  10. 10

    Grouped summaries and validation

    Advanced

    Summarize groups with explicit missing-data and input rules.

    Open whenever you’re ready
    Open chapter: Grouped summaries and validation
  11. 11

    Lexical scope and forced configuration

    Advanced

    Keep function factories predictable when arguments are lazy.

    Open whenever you’re ready
    Open chapter: Lexical scope and forced configuration
  12. 12

    Conditions and reliable cleanup

    Advanced

    Recover narrowly and restore temporary state.

    Open whenever you’re ready
    Open chapter: Conditions and reliable cleanup
  13. 13

    Reproducible sampling and simulation

    Advanced

    Control random state while keeping statistical claims honest.

    Open whenever you’re ready
    Open chapter: Reproducible sampling and simulation

PUT IT TOGETHER

Final assessment & certificate

30 multiple-choice questions and 2 written coding problems. Pass the knowledge section at 80% overall and at least 50% in every chapter area, complete and review the written practice, and meet the attempt-integrity checks to unlock your certificate.

The certificate records a CodeQuest foundations assessment. Written work is self-reviewed; identity and independent proficiency are not verified.

Open final assessment

Take an issuer-recorded assessment with a verifiable certificate

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