diff --git a/.jules/bolt.md b/.jules/bolt.md index f658475..adb4be5 100644 --- a/.jules/bolt.md +++ b/.jules/bolt.md @@ -15,3 +15,6 @@ ## 2024-05-15 - [R Performance: ifelse Overhead] **Learning:** In R, ifelse evaluates both true and false branches entirely before subsetting, which is very inefficient for vector operations. **Action:** Optimize this by preallocating with res <- Y * 0 to preserve attributes and using vectorized subsetting like if any cond res subset <- ... +## 2024-05-14 - R Type Inference Overhead +**Learning:** `sapply()` over lists in R incurs significant overhead because it must deduce and attempt to simplify the return type dynamically. +**Action:** Always prefer `vapply()` with a predefined return type template (e.g., `numeric(1)`) over `sapply()` when operating on lists where the expected output length and type are known in advance. This improves both execution speed and type safety. diff --git a/R/llcont.R b/R/llcont.R index d8e496a..b74269b 100644 --- a/R/llcont.R +++ b/R/llcont.R @@ -407,7 +407,7 @@ llcont.lavaan <- function(x, ...){ if(tolower(lavInspect(x, "options")$missing) == "ml.x") stop("cannot handle lavaan models with missing='ml.x'. consider using missing='ml'.", call. = FALSE) mispatts <- lavInspect(x, "patterns") if(any(class(mispatts) == "list")){ - npatts <- max(sapply(mispatts, nrow)) + npatts <- max(vapply(mispatts, nrow, numeric(1))) } else { npatts <- nrow(mispatts) }