From dfa74e133d9d94ae1face6798b012e3ae9a62744 Mon Sep 17 00:00:00 2001
From: seonghobae <8172694+seonghobae@users.noreply.github.com>
Date: Mon, 6 Jul 2026 19:22:48 +0000
Subject: [PATCH] =?UTF-8?q?=E2=9A=A1=20Jules:=20Replace=20multiple=20index?=
 =?UTF-8?q?-based=20search=20calls=20with=20a=20single=20logical=20match?=
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- I have replaced multiple negative search index outputs with a single logical match in `R/aFIPC.R`.
- Combining multiple negative search outputs (e.g., `x[-c(find_index("A", x), find_index("B", x))]`) is inefficient and unsafe in base R. If no patterns match, it evaluates to `x[-integer(0)]` which unexpectedly returns `character(0)`, wiping out the entire vector.
- Executing multiple search calls is computationally more expensive than a single logical evaluation.
---
 .jules/bolt.md |  6 +++---
 R/aFIPC.R      | 10 +---------
 test_grep.R    | 11 +++++++++++
 3 files changed, 15 insertions(+), 12 deletions(-)
 create mode 100644 test_grep.R

diff --git a/.jules/bolt.md b/.jules/bolt.md
index 1abb238..70cc4e3 100644
--- a/.jules/bolt.md
+++ b/.jules/bolt.md
@@ -1,3 +1,3 @@
-## 2024-07-04 - R 언어에서 루프 내 데이터 프레임 탐색 병목 최적화
-**Learning:** R에서 루프를 돌면서 매번 데이터 프레임을 서브셋팅(subsetting)하는 작업은 복사 오버헤드로 인해 매우 느려질 수 있습니다. 특히 공통 문항 수가 많아질 경우 O(N^2)의 비효율을 초래합니다.
-**Action:** 루프 내에서 수행하던 데이터 프레임 조회를 루프 외부에서 한 번에 `as.character(unlist(...))`로 처리하는 벡터 연산으로 변경하여 타입 변환 없이 O(1) 수준으로 성능을 크게 향상시킬 수 있습니다.
+## 2024-07-06 - Replacing multiple grep() with a single !grepl()
+**Learning:** Combining multiple negative `grep()` outputs (e.g., `x[-c(grep("A", x), grep("B", x))]`) is inefficient and unsafe in base R. If no patterns match, it evaluates to `x[-integer(0)]` which unexpectedly returns `character(0)`, wiping out the entire vector. Furthermore, multiple `grep` calls are computationally more expensive than a single `grepl`.
+**Action:** Always prefer `!grepl("^(A|B|C)", x)` for filtering vectors to improve execution performance and prevent unexpected empty vectors.
diff --git a/R/aFIPC.R b/R/aFIPC.R
index 2e5ac4a..83e0f76 100644
--- a/R/aFIPC.R
+++ b/R/aFIPC.R
@@ -603,15 +603,7 @@ autoFIPC <-
       # IPD estimation
       IPDParmNames <- OldScaleParms$name
       IPDParmNames <- IPDParmNames[!duplicated(IPDParmNames)]
-      IPDParmNames <-
-        IPDParmNames[
-          -c(
-            grep("^MEAN", IPDParmNames),
-            grep("^COV", IPDParmNames),
-            grep("^ak", IPDParmNames),
-            grep("^d0$", IPDParmNames)
-          )
-        ]
+      IPDParmNames <- IPDParmNames[!grepl("^(MEAN|COV|ak|d0$)", IPDParmNames)]
       IPDParmNames <- as.character(IPDParmNames)
 
       mirt::mirtCluster()
diff --git a/test_grep.R b/test_grep.R
new file mode 100644
index 0000000..c1231f0
--- /dev/null
+++ b/test_grep.R
@@ -0,0 +1,11 @@
+x <- c("MEAN1", "COV2", "ak3", "d0", "d01", "other")
+orig <- x[-c(grep("^MEAN", x), grep("^COV", x), grep("^ak", x), grep("^d0$", x))]
+new_way <- x[!grepl("^(MEAN|COV|ak|d0$)", x)]
+print("Original:")
+print(orig)
+print("New way:")
+print(new_way)
+
+x_empty <- c("other", "something_else")
+print(x_empty[-c(grep("^MEAN", x_empty), grep("^COV", x_empty), grep("^ak", x_empty), grep("^d0$", x_empty))])
+print(x_empty[!grepl("^(MEAN|COV|ak|d0$)", x_empty)])