feat: improved exponent calculation for numba

qiboteam · Mar 5, 2024 · e658274 · e658274
1 parent 5b2cc23
commit e658274
Showing 1 changed file with 5 additions and 12 deletions.
diff --git a/src/qibojit/backends/clifford_operations_cpu.py b/src/qibojit/backends/clifford_operations_cpu.py
@@ -268,18 +268,11 @@ def _rowsum(symplectic_matrix, h, i, nqubits, determined=False):
  g_xi_xh = xi.copy()
  g_zi_zh = xi.copy()
  for j in prange(len(h)): # pylint: disable=not-an-iterable
- exp = np.zeros(nqubits, dtype=uint64)
- x1_eq_z1 = (xi[j] ^ zi[j]) == False
- x1_neq_z1 = ~x1_eq_z1
- x1_eq_0 = xi[j] == False
- x1_eq_1 = ~x1_eq_0
- ind2 = x1_eq_z1 & x1_eq_1
- ind3 = x1_eq_1 & x1_neq_z1
- ind4 = x1_eq_0 & x1_neq_z1
- exp[ind2] = zh[j, ind2].astype(uint64) - xh[j, ind2].astype(uint64)
- exp[ind3] = zh[j, ind3].astype(uint64) * (2 * xh[j, ind3].astype(uint64) - 1)
- exp[ind4] = xh[j, ind4].astype(uint64) * (1 - 2 * zh[j, ind4].astype(uint64))
-
+ exp = (
+ 2 * (xi[j] * xh[j] * (zh[j] - zi[j]) + zi[j] * zh[j] * (xi[j] - xh[j]))
+ - xi[j] * zh[j]
+ + xh[j] * zi[j]
+ )
  r = (
  2 * symplectic_matrix[h[j], -1]
  + 2 * symplectic_matrix[i[j], -1]