Draw latex diagrams for bloqs using QPIC (#908)

* Draw latex diagrams for bloqs using QPIC

* A bunch of improvements

* Add latex type to show_bloq method and delegate to show_bloq_via_qpic

Author: tanujkhattar

qualtran/bloqs/basic_gates/global_phase.py

@@ -54,6 +54,9 @@ def adjoint(self) -> 'GlobalPhase':
     def pretty_name(self) -> str:
         return 'GPhase'
 
+    def __str__(self) -> str:
+        return str(self.coefficient)
+
     def _t_complexity_(self) -> 'TComplexity':
         return TComplexity()
 

qualtran/cirq_interop/_cirq_to_bloq.py

@@ -162,8 +162,20 @@ def cirq_gate(self) -> cirq.Gate:
         return self.gate
 
 
+def _cirq_wire_symbol_to_qualtran_wire_symbol(symbol: str, side: Side) -> 'WireSymbol':
+
+    from qualtran.drawing import Circle, directional_text_box, ModPlus
+
+    if symbol == "@":
+        return Circle(filled=True)
+    if symbol == "@(0)":
+        return Circle(filled=False)
+    if symbol == "X":
+        return ModPlus()
+    return directional_text_box(symbol, side=side)
+
+
 def _wire_symbol_from_gate(gate: cirq.Gate, signature: Signature, soq: 'Soquet') -> 'WireSymbol':
-    from qualtran.drawing import directional_text_box
 
     wire_symbols = cirq.circuit_diagram_info(gate).wire_symbols
     begin = 0
@@ -187,7 +199,7 @@ def _wire_symbol_from_gate(gate: cirq.Gate, signature: Signature, soq: 'Soquet')
                 # bitsize = 1 and shape is non trivial, index into the array of wireshapes.
                 symbol = np.array(wire_symbols[begin:finish]).reshape(reg.shape)[soq.idx]
         begin = finish
-    return directional_text_box(text=symbol, side=soq.reg.side)
+    return _cirq_wire_symbol_to_qualtran_wire_symbol(symbol, soq.reg.side)
 
 
 def _add_my_tensors_from_gate(

qualtran/drawing/__init__.py

@@ -46,4 +46,11 @@
     format_counts_graph_markdown,
 )
 
-from ._show_funcs import show_bloq, show_bloqs, show_call_graph, show_counts_sigma, show_flame_graph
+from ._show_funcs import (
+    show_bloq,
+    show_bloqs,
+    show_call_graph,
+    show_counts_sigma,
+    show_flame_graph,
+    show_bloq_via_qpic,
+)

qualtran/drawing/_show_funcs.py

@@ -14,6 +14,7 @@
 
 """Convenience functions for showing rich displays in Jupyter notebook."""
 
+import os
 from typing import Dict, Sequence, TYPE_CHECKING, Union
 
 import IPython.display
@@ -23,6 +24,7 @@
 from .flame_graph import get_flame_graph_svg_data
 from .graphviz import PrettyGraphDrawer, TypedGraphDrawer
 from .musical_score import draw_musical_score, get_musical_score_data
+from .qpic_diagram import qpic_diagram_for_bloq
 
 if TYPE_CHECKING:
     import networkx as nx
@@ -36,17 +38,20 @@ def show_bloq(bloq: 'Bloq', type: str = 'graph'):  # pylint: disable=redefined-b
 
     Args:
         bloq: The bloq to show
-        type: Either 'graph', 'dtype', or 'musical_score'. By default, display a directed acyclic
-            graph of the bloq connectivity. If dtype then the connections are
-            labelled with their dtypes rather than bitsizes. Otherwise, draw a
-            musical score diagram.
+        type: Either 'graph', 'dtype', 'musical_score' or 'latex'. By default, display
+            a directed acyclic graph of the bloq connectivity. If dtype then the
+            connections are labelled with their dtypes rather than bitsizes. If 'latex',
+            then latex diagrams are drawn using `qpic`, which should be installed already
+            and is invoked via a subprocess.run() call. Otherwise, draw a musical score diagram.
     """
     if type.lower() == 'graph':
         IPython.display.display(PrettyGraphDrawer(bloq).get_svg())
     elif type.lower() == 'dtype':
         IPython.display.display(TypedGraphDrawer(bloq).get_svg())
     elif type.lower() == 'musical_score':
         draw_musical_score(get_musical_score_data(bloq))
+    elif type.lower() == 'latex':
+        show_bloq_via_qpic(bloq)
     else:
         raise ValueError(f"Unknown `show_bloq` type: {type}.")
 
@@ -84,3 +89,13 @@ def show_flame_graph(*bloqs: 'Bloq', **kwargs):
     """Display hiearchical decomposition and T-complexity costs as a Flame Graph."""
     svg_data = get_flame_graph_svg_data(*bloqs, **kwargs)
     IPython.display.display(IPython.display.SVG(svg_data))
+
+
+def show_bloq_via_qpic(bloq: 'Bloq', width: int = 1000, height: int = 400):
+    """Display latex diagram for bloq by invoking `qpic`. Assumes qpic is already installed."""
+    output_file_path = qpic_diagram_for_bloq(bloq, output_type='png')
+
+    from IPython.display import Image
+
+    IPython.display.display(Image(output_file_path, width=width, height=height))
+    os.remove(output_file_path)