ReadMeFeed / Community knowledge
Real questions. Useful conversations. Find the people who know your stack.
Languages & runtimes · #r
Learn how to diagnose and resolve 'cannot allocate vector' errors in R by identifying memory leaks, optimizing data structures, and managing the garbage collector.
Learn to distinguish between missing packages, failed namespace loads, and compilation errors in R, with ordered checks and targeted fixes.
Learn how to convert a data frame to a data.table and compute sums or means of numeric columns grouped by one or more factor variables with the fast .() syntax.
Learn how data.table’s i‑j‑by syntax speeds up aggregations on multi‑million‑row datasets, with a concrete sales‑summary example, trade‑offs, and verification steps.
When R says object of type closure is not subsettable you are subsetting a function, not data. This guide shows how to diagnose name collisions and missing parentheses, and fix them.
Learn how R's native pipe (|>) and underscore placeholder work, how they differ from magrittr's %>%, and how to migrate production pipelines safely.
R silently repeats shorter vectors to match longer ones in arithmetic and assignment. Learn the recycling rule, see it in action, and guard against silent bugs.
Learn how data.table's := operator updates columns in place, avoiding copies and speeding up grouped manipulations on large R datasets.
Large CSVs choke base read.csv(); data.table's fread() and in-place := cut memory and time. Example shows the swap and warns about aliasing.