From 994cae1369f1436bfdaf5ffa8dec67f8295dde2b Mon Sep 17 00:00:00 2001
From: Kenil shah <kenilshah1505@gmail.com>
Date: Tue, 31 Mar 2026 13:39:25 +0530
Subject: [PATCH] perf: direct element-wise subtraction for LagrangeBasis refs

---
 ipa-multipoint/src/lagrange_basis.rs | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/ipa-multipoint/src/lagrange_basis.rs b/ipa-multipoint/src/lagrange_basis.rs
index 9c272d92..e0e496d8 100644
--- a/ipa-multipoint/src/lagrange_basis.rs
+++ b/ipa-multipoint/src/lagrange_basis.rs
@@ -96,7 +96,18 @@ impl Sub<&LagrangeBasis> for &LagrangeBasis {
     type Output = LagrangeBasis;
 
     fn sub(self, rhs: &LagrangeBasis) -> Self::Output {
-        self.clone() + (-rhs)
+        assert_eq!(
+            self.values.len(),
+            rhs.values.len(),
+            "LagrangeBasis subtraction requires same length"
+        );
+        LagrangeBasis::new(
+            self.values
+                .iter()
+                .zip(rhs.values.iter())
+                .map(|(a, b)| *a - *b)
+                .collect(),
+        )
     }
 }