simplify RE for Sqrt

Author: fedimser

qmath/func/sqrt.py

@@ -73,7 +73,7 @@ def _estimate(self, x: SymbolicQFixed):
             gidney_lelbows=num_elbows,
             gidney_relbows=num_elbows,
             toffs=n + 1 + (n % 2),
-            local_ancillae=2 * x.num_qubits + 1 + 3 * (n % 2) + 3 * r,
+            local_ancillae=2 * n + 1 + 3 * (n % 2) + r,
             active_volume=18.75 * n**2 + (151.5 + 37.5 * (n % 2)) * n + 170.25 * (n % 2) - 225,
         )
         self.get_qc().add_cost_event(cost)

qmath/func/sqrt_re_test.py

@@ -9,9 +9,9 @@
 # @pytest.mark.skipif(not RUN_SLOW_TESTS, reason="slow test")
 @pytest.mark.parametrize("half_arg", [False, True])
 def test_re_sqrt(half_arg: bool):
-    op = Sqrt(half_arg=False)
+    op = Sqrt(half_arg=half_arg)
     re_symbolic = re_symbolic_fixed_point(op)
     re_numeric = lambda assgn: re_numeric_fixed_point(op, assgn)
-    for n in [5, 6, 7, 20, 21]:
-        for radix in [0, 1, 2]:
+    for n in [5, 6] + ([7, 20, 21] if RUN_SLOW_TESTS else []):
+        for radix in [0, 1] + ([2, 5] if RUN_SLOW_TESTS else []):
             verify_re(re_symbolic, re_numeric, {"n": n, "radix": radix})