use zdrot

qiskit-community · Sep 20, 2023 · 857a25d · 857a25d
1 parent 5ca031f
commit 857a25d
Showing 1 changed file with 2 additions and 3 deletions.
diff --git a/python/ffsim/slow/gates/orbital_rotation.py b/python/ffsim/slow/gates/orbital_rotation.py
@@ -11,6 +11,7 @@
 from __future__ import annotations
 
 import numpy as np
+from scipy.linalg.blas import zdrot
 
 
 def gen_orbital_rotation_index_in_place_slow(
@@ -74,7 +75,5 @@ def apply_givens_rotation_in_place_slow(
     phase_conj = phase.conjugate()
     for i, j in zip(slice1, slice2):
         vec[i] *= phase_conj
-        tmp = c * vec[i] + s * vec[j]
-        vec[j] = c * vec[j] - s * vec[i]
-        vec[i] = tmp
+        vec[i], vec[j] = zdrot(vec[i], vec[j], c, s)
         vec[i] *= phase