diff --git a/demos/PauliWebs.ipynb b/demos/PauliWebs.ipynb
index 6ec7d08e..c382e4a3 100644
--- a/demos/PauliWebs.ipynb
+++ b/demos/PauliWebs.ipynb
@@ -28,13 +28,59 @@
},
{
"cell_type": "code",
- "execution_count": 2,
+ "execution_count": 7,
"metadata": {},
"outputs": [
+ {
+ "name": "stdout",
+ "output_type": "stream",
+ "text": [
+ "CNOT(0,1)\n",
+ "CNOT(1,0)\n",
+ "CNOT(2,0)\n",
+ "HAD(2)\n",
+ "CNOT(2,1)\n",
+ "HAD(2)\n",
+ "CNOT(1,0)\n",
+ "CNOT(0,2)\n",
+ "CNOT(1,2)\n",
+ "T(0)\n",
+ "T(1)\n",
+ "HAD(2)\n",
+ "T(2)\n",
+ "HAD(1)\n",
+ "HAD(0)\n",
+ "CNOT(0,2)\n",
+ "CNOT(0,2)\n",
+ "CNOT(1,0)\n",
+ "T(2)\n",
+ "HAD(2)\n",
+ "HAD(1)\n",
+ "CNOT(1,0)\n",
+ "CNOT(0,1)\n",
+ "CNOT(2,1)\n",
+ "T(0)\n",
+ "CNOT(2,0)\n",
+ "T(0)\n",
+ "T(0)\n",
+ "T(0)\n",
+ "CNOT(2,0)\n",
+ "CNOT(0,2)\n",
+ "T(2)\n",
+ "T(1)\n",
+ "T(1)\n",
+ "T(0)\n",
+ "HAD(1)\n",
+ "T(1)\n",
+ "CNOT(1,0)\n",
+ "CNOT(1,2)\n",
+ "CNOT(1,0)\n"
+ ]
+ },
{
"data": {
"text/html": [
- "\n",
+ "\n",
""
],
"text/plain": [
@@ -413,19 +459,20 @@
"source": [
"# Generate a random CNOT, H, T circuit\n",
"random.seed(1330)\n",
- "c = zx.generate.CNOT_HAD_PHASE_circuit(qubits=3, depth=50)\n",
+ "c = zx.generate.CNOT_HAD_PHASE_circuit(qubits=3, depth=40)\n",
+ "for g in c.gates: print(g)\n",
"zx.draw(c)"
]
},
{
"cell_type": "code",
- "execution_count": 3,
+ "execution_count": 8,
"metadata": {},
"outputs": [
{
"data": {
"text/html": [
- "\n",
+ "\n",
""
],
@@ -823,13 +870,13 @@
},
{
"cell_type": "code",
- "execution_count": 4,
+ "execution_count": 9,
"metadata": {},
"outputs": [
{
"data": {
"text/html": [
- "\n",
+ "\n",
""
],
@@ -1208,7 +1255,16 @@
"source": [
"# Once the Pauli webs have been computed, a specific web can be highlighted by `zx.draw` by passing it in as\n",
"# an optional argument. Note that webs change color when they cross Hadamard edges.\n",
- "zx.draw(g, labels=True, pauli_web=webs[87])"
+ "zx.draw(g, labels=True, pauli_web=webs[67])"
+ ]
+ },
+ {
+ "cell_type": "markdown",
+ "metadata": {},
+ "source": [
+ "We now show how this works in some simpler cases. The first is a single T gate.\n",
+ "\n",
+ "The T gate becomes a single, 1-legged phase gadget, connected to the input. This can be implemented by Z-merging a T magic state, then doing either an X or a Y measurement, depending on the parity of the Pauli web."
]
},
{
@@ -1219,7 +1275,7 @@
{
"data": {
"text/html": [
- "\n",
+ "\n",
""
@@ -1593,21 +1649,7 @@
},
"metadata": {},
"output_type": "display_data"
- }
- ],
- "source": [
- "c = zx.qasm(\"\"\"\n",
- "qreg q[1];\n",
- "t q[0];\n",
- "\"\"\")\n",
- "zx.draw(c)"
- ]
- },
- {
- "cell_type": "code",
- "execution_count": 6,
- "metadata": {},
- "outputs": [
+ },
{
"name": "stdout",
"output_type": "stream",
@@ -1618,7 +1660,7 @@
{
"data": {
"text/html": [
- "\n",
+ "\n",
""
],
"text/plain": [
@@ -1995,12 +2037,825 @@
}
],
"source": [
+ "c = zx.qasm(\"\"\"\n",
+ "qreg q[1];\n",
+ "t q[0];\n",
+ "\"\"\")\n",
+ "zx.draw(c)\n",
+ "\n",
"g = c.to_graph()\n",
"zx.full_reduce(g)\n",
"in_circ, out_circ = preprocess(g)\n",
"order, webs = compute_pauli_webs(g)\n",
"print(f'{in_circ.gates} {out_circ.gates}')\n",
- "zx.draw(g)"
+ "\n",
+ "# highlight the web associated to the T spider\n",
+ "zx.draw(g, labels=True, pauli_web=webs[3])"
+ ]
+ },
+ {
+ "cell_type": "markdown",
+ "metadata": {},
+ "source": [
+ "The next example is a circuit with some CNOT gates and a T gate, which can be simplified to a single phase gadget. I'm doing this manually here, since the automated simplifier comes up with a different answer (which is equivalent to this one, up to local Cliffords, but less clear what is going on)."
+ ]
+ },
+ {
+ "cell_type": "code",
+ "execution_count": 6,
+ "metadata": {},
+ "outputs": [
+ {
+ "data": {
+ "text/html": [
+ "\n",
+ ""
+ ],
+ "text/plain": [
+ ""
+ ]
+ },
+ "metadata": {},
+ "output_type": "display_data"
+ },
+ {
+ "name": "stdout",
+ "output_type": "stream",
+ "text": [
+ "[] []\n"
+ ]
+ },
+ {
+ "data": {
+ "text/html": [
+ "\n",
+ ""
+ ],
+ "text/plain": [
+ ""
+ ]
+ },
+ "metadata": {},
+ "output_type": "display_data"
+ }
+ ],
+ "source": [
+ "c = zx.qasm(\"\"\"\n",
+ "qreg q[3];\n",
+ "cx q[0], q[1];\n",
+ "cx q[1], q[2];\n",
+ "t q[2];\n",
+ "cx q[1], q[2];\n",
+ "cx q[0], q[1];\n",
+ "\"\"\")\n",
+ "zx.draw(c)\n",
+ "\n",
+ "# manual ZX simplification to get a single phase gadget\n",
+ "g = c.to_graph()\n",
+ "zx.simplify.gadgetize(g, graphlike=False)\n",
+ "zx.basicrules.strong_comp(g, 5, 7)\n",
+ "zx.simplify.spider_simp(g, quiet=True)\n",
+ "zx.basicrules.strong_comp(g, 3, 6)\n",
+ "zx.simplify.spider_simp(g, quiet=True)\n",
+ "zx.simplify.id_simp(g, quiet=True)\n",
+ "\n",
+ "# pauli web calculation\n",
+ "in_circ, out_circ = preprocess(g)\n",
+ "order, webs = compute_pauli_webs(g)\n",
+ "print(f'{in_circ.gates} {out_circ.gates}')\n",
+ "\n",
+ "# highlight the web associated to the T spider\n",
+ "zx.draw(g, labels=True, pauli_web=webs[15])"
]
},
{
diff --git a/pyzx/__init__.py b/pyzx/__init__.py
index a204d297..3b49a8d8 100644
--- a/pyzx/__init__.py
+++ b/pyzx/__init__.py
@@ -37,6 +37,7 @@
from . import linalg
from . import extract
from . import rules
+from . import basicrules
from . import hrules
from . import optimize
from . import simplify
diff --git a/pyzx/pauliweb.py b/pyzx/pauliweb.py
index 33e5df45..18ac1356 100644
--- a/pyzx/pauliweb.py
+++ b/pyzx/pauliweb.py
@@ -83,8 +83,8 @@ def preprocess(g: BaseGraph[VT,ET]):
#g.normalize()
gadgetize(g)
gadgets = set(v for v in g.vertices() if g.is_phase_gadget(v))
- boundary_spiders = set(v for v in g.vertices() if any(g.type(w) == VertexType.BOUNDARY for w in g.neighbors(v)))
- to_rg(g, init_z=boundary_spiders, init_x=gadgets)
+ #boundary_spiders = set(v for v in g.vertices() if any(g.type(w) == VertexType.BOUNDARY for w in g.neighbors(v)))
+ to_rg(g, init_z=None, init_x=gadgets)
in_circ = Circuit(len(g.inputs()))
for j,i in enumerate(g.inputs()):
diff --git a/pyzx/simplify.py b/pyzx/simplify.py
index 1f3ce5da..b11c0640 100644
--- a/pyzx/simplify.py
+++ b/pyzx/simplify.py
@@ -367,15 +367,20 @@ def to_rg(g: BaseGraph[VT,ET], init_z: Optional[Set[VT]]=None, init_x: Optional[
for e in g.incident_edges(v):
g.set_edge_type(e, toggle_edge(g.edge_type(e)))
-def gadgetize(g: BaseGraph[VT,ET]):
+def gadgetize(g: BaseGraph[VT,ET], graphlike:bool=True):
"""Convert every non-Clifford phase to a phase gadget"""
for v in list(g.vertices()):
p = g.phase(v)
if not phase_is_clifford(p) and g.vertex_degree(v) > 1:
- x = g.add_vertex(VertexType.Z, -1, g.row(v))
y = g.add_vertex(VertexType.Z, -2, g.row(v))
- g.add_edge((x, y), EdgeType.HADAMARD)
- g.add_edge((v, x), EdgeType.HADAMARD)
+ if graphlike:
+ x = g.add_vertex(VertexType.Z, -1, g.row(v))
+ g.add_edge((x, y), EdgeType.HADAMARD)
+ g.add_edge((v, x), EdgeType.HADAMARD)
+ else:
+ x = g.add_vertex(VertexType.X, -1, g.row(v))
+ g.add_edge((x, y), EdgeType.SIMPLE)
+ g.add_edge((v, x), EdgeType.SIMPLE)
g.set_phase(y, p)
g.set_phase(v, 0)