public static Complex CalcAmpFlat(CircuitOp[] remaining_circuit, int circuitpos, int inital_state, int target_state)
{
int curridx = -1; // number of active elements in the queue.
WorkUnit[] worklist = new WorkUnit[16];
CircuitOp current_gate = remaining_circuit[circuitpos - 1];
// wuDefault(ref worklist[0]); // ref types don't work in Kiwi, fine
// WorkUnit firstelement = wuDefault();
worklist[0].target = target_state;
worklist[0].depth = circuitpos;
// add_preds(ref worklist[0], current_gate);
curridx = 0; // if -1, return.
WorkUnit current;
Complex lasteval;
// while (curridx > 0) { // valid indices for the work list
// Kiwi.Pause();
// current = worklist[curridx-1];
// current_gate = remaining_circuit[curridx-1];
// if (can_evaluate(current)) {
// lasteval = evaluate(current, current_gate);
// curridx -= 1; // pop off the stack.
// } else {
// Console.WriteLine("need to addd to the worklist, cant do that yet!");
// curridx -= 1;
// }
// }
Console.WriteLine("RAN OFF THE END OF THE WORKLIST!");
return(new Complex(0.0, 0.0));
}
public static WorkUnit add_preds(ref WorkUnit current, CircuitOp gate)
{
int[] predecessors = state_ball(current.target, gate.qubits);
switch (gate.op)
{
case Op.H:
current.dep_done_0 = false; current.dep_done_1 = false;
current.dep_done_2 = true; current.dep_done_3 = true;
current.dep_target_0 = predecessors[0]; current.dep_target_1 = predecessors[1];
current.dep_target_2 = 0; current.dep_target_3 = 0;
break;
case Op.CNOT:
current.dep_done_0 = false; current.dep_done_1 = false;
current.dep_done_2 = false; current.dep_done_3 = false;
current.dep_target_0 = predecessors[0]; current.dep_target_1 = predecessors[1];
current.dep_target_2 = predecessors[0]; current.dep_target_3 = predecessors[1];
break;
default:
Console.WriteLine("UNKNOWN OPERATION!");
break;
}
return(current);
}
//static int debuglevel = 0;
public static Complex CalcAmp(CircuitOp[] remaining_circuit, int circuitpos, int inital_state, int target_state)
{
// class-based dynamic dispatch errors out if the return value from this wunction is created with operator new inside a branch that is conditional on remaining_circuit.Length.
// so
double realpart, imagpart;
if (circuitpos == 0)
{
//Console.WriteLine("{0}Base case for target {1}", new string (' ', debuglevel), target_state);
realpart = (target_state == inital_state) ? 1.0 : 0.0;
imagpart = 0.0;
}
else
{
//Console.WriteLine("{0}evaluating for lvl {1} target {2}", new string (' ', debuglevel), circuitpos, target_state);
CircuitOp current_gate = remaining_circuit[circuitpos - 1];
int[] predecessors = state_ball(target_state, current_gate.qubits);
Complex[] predecessor_amp = new Complex[predecessors.Length];
for (int i = 0; i < predecessors.Length; i++)
{
Kiwi.Pause();
//debuglevel += 1;
predecessor_amp[i] = CalcAmp(remaining_circuit, circuitpos - 1, inital_state, predecessors[i]);
//debuglevel -= 1;
}
Complex resamp = zero;
for (int i = 0; i < predecessors.Length; i++)
{
switch (current_gate.op)
{
case Op.H:
resamp = resamp + H_select(
partial_trace(predecessors[i], current_gate.qubits),
predecessor_amp[i],
partial_trace(target_state, current_gate.qubits)
);
break;
case Op.CNOT:
resamp = resamp + CNOT_select(
partial_trace(predecessors[i], current_gate.qubits),
predecessor_amp[i],
partial_trace(target_state, current_gate.qubits)
);
break;
default:
Console.WriteLine("UNKNOWN OPERATION!");
break;
}
}
realpart = resamp.real; //(target_state == inital_state) ? 1.0 : 0.0;
imagpart = resamp.imag;
}
return(new Complex(realpart, imagpart));
}
public static Complex evaluate(WorkUnit current, CircuitOp current_gate)
{
Complex resamp = zero;
switch (current_gate.op)
{
case Op.H:
resamp = resamp + H_select(
partial_trace(current.dep_target_0, current_gate.qubits),
current.dep_amp_0,
partial_trace(current.target, current_gate.qubits));
resamp = resamp + H_select(
partial_trace(current.dep_target_1, current_gate.qubits),
current.dep_amp_1,
partial_trace(current.target, current_gate.qubits));
break;
case Op.CNOT:
resamp = resamp + CNOT_select(
partial_trace(current.dep_target_0, current_gate.qubits),
current.dep_amp_0,
partial_trace(current.target, current_gate.qubits));
resamp = resamp + CNOT_select(
partial_trace(current.dep_target_1, current_gate.qubits),
current.dep_amp_1,
partial_trace(current.target, current_gate.qubits));
resamp = resamp + CNOT_select(
partial_trace(current.dep_target_2, current_gate.qubits),
current.dep_amp_2,
partial_trace(current.target, current_gate.qubits));
resamp = resamp + CNOT_select(
partial_trace(current.dep_target_3, current_gate.qubits),
current.dep_amp_3,
partial_trace(current.target, current_gate.qubits));
break;
default:
Console.WriteLine("UNKNOWN OPERATION!");
break;
}
return(resamp);
}
static void Main()
{
CircuitOp[] circuit = new CircuitOp[2];
circuit[0] = new CircuitOp(Op.H, new int[] { 0 });
circuit[1] = new CircuitOp(Op.H, new int[] { 1 });
// circuit[2] = new CircuitOp(Op.CNOT, new int[] { 1, 0 });
//
//
// circuit[3] = new CircuitOp(Op.H, new int[] { 0 });
// circuit[4] = new CircuitOp(Op.H, new int[] { 1 });
int tgt = 0;
Complex res = CalcAmpFlat(circuit, circuit.Length, 0, tgt);
Console.WriteLine("HH|{0}> on |0> is {1}", tgt, res.real);
// Complex res = H_select(0, new Complex(1.0, 0.0), 0);
// for (int tgt=0; tgt<4; tgt++) {
// Complex res = CalcAmp(circuit, circuit.Length, 2, tgt);
// Console.WriteLine("H|{0}> on |2> is {1}", tgt, res.real);
// }
// Console.WriteLine("0 with bit set at idx 1 is {0}", insert_bit(0, true, 1) ); // true
//
// Console.WriteLine("0 with bit set at idx 1 is {0}", insert_bit(0, false, 1) ); // false, does not clear the bit.
//
// Console.WriteLine("trace of 1 out of |010> is {0}", partial_trace(2, new int[] {1}));
//
//
// Console.WriteLine("stateball for |000> on pos 1 is");
// int[] stateball = state_ball(0, new int[] {1});
// for (int i=0; i<stateball.Length; i++) {
// Console.WriteLine("|{0}>", stateball[i]);
// }
done = true;
}
