Fix handling of empty arguments in ProgressiveIndexOf

1 files changed, 1 insertions, 1 deletions

diff --git a/src/r.bqn b/src/r.bqn
index 0010fc9f..3ebd50b3 100644
--- a/src/r.bqn
+++ b/src/r.bqn
@@ -545,7 +545,7 @@ ReorderAxesInv←{
 ⍉ ← Transpose      ⊘ ReorderAxes
 
 OccurrenceCount ← ⊐˜(⊢-⊏)⍋∘⍋
-ProgressiveIndexOf ← {𝕨⊐○(≍˘⟜OccurrenceCount𝕨⊸⊐)𝕩}
+ProgressiveIndexOf ← {𝕨⊐○((≠∾2˙)⥊·≍˘⟜OccurrenceCount𝕨⊸⊐)𝕩}
 
 ⊏ ← (<0)⊸GetCells  ⊘ (ToArray⊸(SelSub _onAxes_ 1))
 ⊑ ↩ (0⊑⥊)          ⊘ Pick