Creating a Density Plot with a VLine as Cutoff: A Step-by-Step Guide to Shading Above or Below the Threshold in R

Resolving Compilation Issues with glmnet in Amazon Linux Docker Images

Understanding Double Quotes vs Single Quotes in R: Why Preference Lies with Double Quots

Understanding and Using OAuth with TwitteR for Secure Twitter API Access in R

Here's a revised version of your code with additional comments and explanations:

Optimizing Partial Matching in R: A Guide to pmatch, Apply, and Beyond

Customizing the Legend Title in ggplot2: A Guide to Labels, Legends, and More

Converting NetCDF Files in R: A Step-by-Step Guide for Longitude-Latitude Grids

Converting R Lists to JSON-Like Strings Compatible with Cypher DSL

Implementing Object-Oriented Programming (OOPs) in R Shiny Applications: Best Practices and Advanced Techniques