Requirements
- Target platform
- OpenClaw
- Install method
- Manual import
- Extraction
- Extract archive
- Prerequisites
- OpenClaw
- Primary doc
- SKILL.md
Avoid common R mistakes — vectorization traps, NA propagation, factor surprises, and indexing gotchas.
Avoid common R mistakes — vectorization traps, NA propagation, factor surprises, and indexing gotchas.
Hand the extracted package to your coding agent with a concrete install brief instead of figuring it out manually.
I downloaded a skill package from Yavira. Read SKILL.md from the extracted folder and install it by following the included instructions. Tell me what you changed and call out any manual steps you could not complete.
I downloaded an updated skill package from Yavira. Read SKILL.md from the extracted folder, compare it with my current installation, and upgrade it while preserving any custom configuration unless the package docs explicitly say otherwise. Summarize what changed and any follow-up checks I should run.
Loops are slow — use apply(), lapply(), sapply(), or purrr::map() Vectorized functions operate on whole vectors — sum(x) not for (i in x) total <- total + i ifelse() is vectorized — if is not, use ifelse() for vector conditions Column operations faster than row — R is column-major
R is 1-indexed — first element is x[1], not x[0] x[0] returns empty vector — not error, silent bug Negative index excludes — x[-1] removes first element [[ extracts single element — [ returns subset (list stays list) df[, 1] drops to vector — use df[, 1, drop = FALSE] to keep data frame
NA propagates — 1 + NA is NA, NA == NA is NA Use is.na() to check — not x == NA Most functions need na.rm = TRUE — mean(x) returns NA if any NA present na.omit() removes rows with any NA — may lose data unexpectedly complete.cases() returns logical vector — rows without NA
Old R converted strings to factors by default — use stringsAsFactors = FALSE or modern R levels() shows categories — but factor values are integers internally Adding new value not in levels gives NA — use factor(x, levels = c(old, new)) as.numeric(factor) gives level indices — use as.numeric(as.character(factor)) for values Dropping unused levels: droplevels() — or factor() again
Shorter vector recycled to match longer — c(1,2,3) + c(10,20) gives 11, 22, 13 No error if lengths aren't multiples — just warning, easy to miss Single values recycle intentionally — x + 1 adds 1 to all elements
Tibble never converts strings to factors — safer defaults Tibble never drops dimensions — df[, 1] stays tibble Tibble prints better — shows type, doesn't flood console as_tibble() to convert — from tibble or dplyr package
<- is idiomatic R — = works but avoided in style guides <<- assigns to parent environment — global assignment, usually a mistake -> right assignment exists — rarely used, confusing
Functions look up in parent environment — can accidentally use global variable Local variable shadows global — same name hides outer variable local() creates isolated scope — variables don't leak out
T and F can be overwritten — use TRUE and FALSE always 1:length(x) fails on empty x — gives c(1, 0), use seq_along(x) sample(5) vs sample(c(5)) — different! first gives 1:5 permutation String splitting: strsplit() returns list — even for single string
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