From 546c2c6e570ca07dd8f77b86c59efdbbd18adb20 Mon Sep 17 00:00:00 2001
From: kss2k <slupphaugkjell@gmail.com>
Date: Tue, 17 Mar 2026 08:56:27 +0100
Subject: [PATCH 1/4] Refactor code for `compositeRVCOV()`

---
 R/reliablity_single_item.R | 62 ++++++++++++++++----------------------
 1 file changed, 26 insertions(+), 36 deletions(-)

diff --git a/R/reliablity_single_item.R b/R/reliablity_single_item.R
index d8b5e5f3..358de63c 100644
--- a/R/reliablity_single_item.R
+++ b/R/reliablity_single_item.R
@@ -598,47 +598,37 @@ calcAVE <- function(lambda.std, lV) {
 }
 
 
-getCompositeDenominator <- function(lV, parTable, cfa, scale.corrected) {
-  measr   <- parTable[parTable$lhs == lV & parTable$op == "=~", ]
-  inds    <- unique(measr$rhs)
-  mats    <- lavaan::lavInspect(cfa, what = "coef")
-  if (scale.corrected) {
-    sum(as.vector(mats$lambda[inds, lV]))
-  } else {
-    length(inds)  # rowMeans: divide sum by k
-  }
-}
+getCompositeRVCOV <- function(lVs, parTable, cfa, scale.corrected) {
+  matrices <- lavaan::lavInspect(cfa, what = "coef")
+  lambda   <- matrices$lambda
+  theta    <- matrices$theta
 
+  inds <- rownames(lambda)[apply(lambda, MARGIN = 1L, FUN = \(x) any(x != 0))]
+  lambda <- lambda[inds, lVs, drop = FALSE]
+  theta  <- theta[inds, inds, drop = FALSE]
 
-getCompositeRVCOV <- function(lVs, parTable, cfa, scale.corrected) {
-  # Build Theta blocks and denominators
-  mats   <- lavaan::lavInspect(cfa, what = "coef")
-  thetaF <- mats$theta
+  I <- lambda
+  I[I != 0] <- 1
 
-  # item lists per LV
-  item_list <- lapply(lVs, function(lv)
-    unique(parTable[parTable$lhs == lv & parTable$op == "=~", "rhs"])
-  )
-  names(item_list) <- lVs
+  T <- t(I) %*% theta %*% I
 
-  # denominators D_f
-  denom <- vapply(lVs, function(lv)
-    getCompositeDenominator(lv, parTable, cfa, scale.corrected),
-    numeric(1)
-  )
+  if (scale.corrected) {
+    l <- apply(lambda, MARGIN = 2L, FUN = sum)
+
+    l.inv <- 1 / l
+    l.inv[l <= 0] <- 1L
 
-  p <- length(lVs)
-  resCov <- matrix(0, p, p, dimnames = list(lVs, lVs))
-
-  for (i in seq_len(p)) {
-    Ii <- item_list[[i]]
-    for (j in i:p) {
-      Ij <- item_list[[j]]
-      block_sum <- sum(thetaF[Ii, Ij, drop = FALSE])
-      val <- block_sum / (denom[i] * denom[j])
-      resCov[i, j] <- val
-      resCov[j, i] <- val
+    if (length(l.inv) > 1) {
+      L.inv <- diag(l.inv)
+      dimnames(L.inv) <- list(names(l.inv), names(l.inv))
+
+    } else {
+      L.inv <- matrix(l.inv, nrow = 1, ncol = 1)
+      dimnames(L.inv) <- list(names(l.inv), names(l.inv))
     }
+
+    T <- L.inv %*% T %*% L.inv
   }
-  resCov
+
+  T
 }

From 9f7125e0425f24b24740b8b57159eab2b053f5b3 Mon Sep 17 00:00:00 2001
From: kss2k <slupphaugkjell@gmail.com>
Date: Tue, 17 Mar 2026 09:18:05 +0100
Subject: [PATCH 2/4] Fix codex comments

---
 R/reliablity_single_item.R | 29 ++++++++++++-----------------
 1 file changed, 12 insertions(+), 17 deletions(-)

diff --git a/R/reliablity_single_item.R b/R/reliablity_single_item.R
index 358de63c..757a1ace 100644
--- a/R/reliablity_single_item.R
+++ b/R/reliablity_single_item.R
@@ -607,28 +607,23 @@ getCompositeRVCOV <- function(lVs, parTable, cfa, scale.corrected) {
   lambda <- lambda[inds, lVs, drop = FALSE]
   theta  <- theta[inds, inds, drop = FALSE]
 
-  I <- lambda
-  I[I != 0] <- 1
-
+  I <- sign(lambda)
   T <- t(I) %*% theta %*% I
 
-  if (scale.corrected) {
-    l <- apply(lambda, MARGIN = 2L, FUN = sum)
+  .f <- if (scale.corrected) sum else length
 
-    l.inv <- 1 / l
-    l.inv[l <= 0] <- 1L
+  l <- apply(lambda, MARGIN = 2L, FUN = .f)
+  l.inv <- 1 / l
+  l.inv[l <= 0] <- 1L
 
-    if (length(l.inv) > 1) {
-      L.inv <- diag(l.inv)
-      dimnames(L.inv) <- list(names(l.inv), names(l.inv))
+  if (length(l.inv) > 1) {
+    L.inv <- diag(l.inv)
+    dimnames(L.inv) <- list(names(l.inv), names(l.inv))
 
-    } else {
-      L.inv <- matrix(l.inv, nrow = 1, ncol = 1)
-      dimnames(L.inv) <- list(names(l.inv), names(l.inv))
-    }
-
-    T <- L.inv %*% T %*% L.inv
+  } else {
+    L.inv <- matrix(l.inv, nrow = 1, ncol = 1)
+    dimnames(L.inv) <- list(names(l.inv), names(l.inv))
   }
 
-  T
+  L.inv %*% T %*% L.inv
 }

From 19c0bf151390ee42e2ce6b8cc687e51dad33f606 Mon Sep 17 00:00:00 2001
From: kss2k <slupphaugkjell@gmail.com>
Date: Tue, 17 Mar 2026 09:20:45 +0100
Subject: [PATCH 3/4] Don't use sign(I)

---
 R/reliablity_single_item.R | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/R/reliablity_single_item.R b/R/reliablity_single_item.R
index 757a1ace..b6e09d78 100644
--- a/R/reliablity_single_item.R
+++ b/R/reliablity_single_item.R
@@ -607,7 +607,9 @@ getCompositeRVCOV <- function(lVs, parTable, cfa, scale.corrected) {
   lambda <- lambda[inds, lVs, drop = FALSE]
   theta  <- theta[inds, inds, drop = FALSE]
 
-  I <- sign(lambda)
+  I <- lambda
+  I[I!=0] <- 1
+
   T <- t(I) %*% theta %*% I
 
   .f <- if (scale.corrected) sum else length

From fbd7de117bd6a8ea32e9685b873c649481c49e8c Mon Sep 17 00:00:00 2001
From: kss2k <slupphaugkjell@gmail.com>
Date: Tue, 17 Mar 2026 09:26:01 +0100
Subject: [PATCH 4/4] Check non-zero values, not length

---
 R/reliablity_single_item.R | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/R/reliablity_single_item.R b/R/reliablity_single_item.R
index b6e09d78..0386d1fb 100644
--- a/R/reliablity_single_item.R
+++ b/R/reliablity_single_item.R
@@ -612,9 +612,9 @@ getCompositeRVCOV <- function(lVs, parTable, cfa, scale.corrected) {
 
   T <- t(I) %*% theta %*% I
 
-  .f <- if (scale.corrected) sum else length
+  FUN <- if (scale.corrected) sum else \(x) sum(x != 0)
 
-  l <- apply(lambda, MARGIN = 2L, FUN = .f)
+  l <- apply(lambda, MARGIN = 2L, FUN = FUN)
   l.inv <- 1 / l
   l.inv[l <= 0] <- 1L