optimize stabilizer circuit gate application

Author: refraction-ray

tensorcircuit/fgs.py

@@ -28,7 +28,6 @@ def onehot_matrix(i: int, j: int, N: int) -> Tensor:
 
 # TODO(@refraction-ray): efficiency benchmark with jit
 # TODO(@refraction-ray): FGS mixed state support?
-# TODO(@refraction-ray): overlap?
 # TODO(@refraction-ray): fermionic logarithmic negativity
 
 

tensorcircuit/stabilizercircuit.py

@@ -96,10 +96,12 @@ def apply_general_gate(
 
         if name.lower() in self.gate_map:
             # self._stim_circuit.append(gate_map[name.lower()], list(index))
-            instruction = f"{self.gate_map[name.lower()]} {' '.join(map(str, index))}"
+            gn = self.gate_map[name.lower()]
+            instruction = f"{gn} {' '.join(map(str, index))}"
             self._stim_circuit.append_from_stim_program_text(instruction)
             # append is much slower
-            self.current_sim.do(stim.Circuit(instruction))
+            # self.current_sim.do(stim.Circuit(instruction))
+            getattr(self.current_sim, gn.lower())(*index)
         else:
             raise ValueError(f"Gate {name} is not supported in stabilizer simulation")