1 files changed, 6 insertions, 4 deletions
diff --git a/spec/reference.bqn b/spec/reference.bqn
index 61e5313a..ea0db2a5 100644
--- a/spec/reference.bqn
+++ b/spec/reference.bqn
@@ -145,8 +145,9 @@ Range←{
 Pick1←{
   ! 1=≠≢𝕨
   ! 𝕨=○≠s←≢𝕩
-  ! ∧´Nat¨𝕨
-  ! ∧´𝕨<s
+  ! ∧´Int¨𝕨
+  ! ∧´𝕨(≥⟜-∧<)s
+  𝕨↩𝕨+s×𝕨<0
   (⥊𝕩)⊑˜0(⊑⟜𝕨+⊑⟜s×⊢)´↕≠𝕨
 }
 Pickd←(∨´IsArray¨)◶Pick1‿{Pickd⟜𝕩¨𝕨}
@@ -251,8 +252,9 @@ _onAxes_←{
 
 SelSub←{
   ! IsArray 𝕨
-  ! Nat¨ 𝕨
-  ! 𝕨 <¨ ≠𝕩
+  ! Int¨ 𝕨
+  ! ∧´⥊ 𝕨 (≥⟜-∧<) ≠𝕩
+  𝕨↩𝕨+(≠𝕩)×𝕨<0
   c←×´s←1 Cell 𝕩
   ⊑⟜(⥊𝕩)¨(c×𝕨)+⌜s⥊↕c
 }