Summary
Congratulations!
You’ve completed the Intermediate R section and significantly expanded your programming capabilities. Let’s review what you’ve accomplished:
What You’ve Mastered
- Handled parameters with default values and the
...ellipsis for variable-length arguments - Used anonymous functions (
\\(x) ...) and higher-order functions (Filter,Map, sappl`y) - Added comments and documentation for clarity
- Designed clean, reusable, well-structured functions
- Imported and organized code effectively using
library()andsource() - Used built-in base R functions (e.g., math, date/time, file utilities)
- Created custom scripts for reuse across projects
- Called specific package functions with the
::operator - Followed best practices for readable and testable code
- Understood common condition types (errors, warnings, messages)
- Used
tryCatch()andfinallyfor controlled error management - Defined custom conditions for domain-specific use cases
- Practiced debugging and robust programming techniques
Real-World Applications You Built
- BMI Calculator – a simple script (
bmi_calculator.R) that computes Body Mass Index (BMI) - Medication Dosage Calculator – a function that calculates a child’s drug dosage based on weight
- Heart Rate Evaluator – a function that classifies a resting heart rate
Key Programming Principles You Now Understand:
- Break big problems into smaller, logical functions
- Group related logic into scripts and eventually packages
- Use
if (sys.nframe() == 0)to protect self-test blocks in sourced files
- Anticipate and validate inputs
- Provide clear, actionable error messages
- Catch specific conditions with
tryCatch()instead of generic handlers
- Add inline comments explaining purpose and assumptions
- Follow snake_case naming conventions
- Write simple test calls for critical functions
What You Can Build Now
- Multi-file R programs with good structure
- Programs that handle files and user input safely
- Utility scripts that others can
source()and use - Apps with graceful error handling and informative output
You’re ready for Data Analysis with R, where you’ll apply these skills to real-world datasets using powerful packages like:
dplyr— for data manipulationggplot2— for visualizationtidyr— for reshaping data- Base R statistics and
statspackage — for hypothesis testing
Next Steps:
The foundation you’ve built here will serve you well as we move into Data Analysis with R, where you’ll apply these skills to real-world data problems using powerful packages like dplyr, ggplot2, and stats.
Remember:
The best way to master R is through consistent practice.
Type out the examples.
Experiment with your own variations.
Break your code. Fix it. Learn from it.
Every function you write strengthens your foundation.