Even more features for G.visualize

Author: adamnsch

graphdatascience/graph/graph_object.py

@@ -1,4 +1,5 @@
 from __future__ import annotations
+from itertools import chain
 
 import colorsys
 import random
@@ -82,7 +83,6 @@ def node_count(self) -> int:
         """
         Returns:
             the number of nodes in the graph
-
         """
         return self._graph_info(["nodeCount"])  # type: ignore
 
@@ -191,7 +191,6 @@ def drop(self, failIfMissing: bool = False) -> "Series[str]":
 
         Returns:
             the result of the drop operation
-
         """
         result = self._query_runner.call_procedure(
             endpoint="gds.graph.drop",
@@ -205,7 +204,6 @@ def creation_time(self) -> Any:  # neo4j.time.DateTime not exported
         """
         Returns:
             the creation time of the graph
-
         """
         return self._graph_info(["creationTime"])
 
@@ -236,12 +234,56 @@ def __repr__(self) -> str:
 
     def visualize(
         self,
-        notebook: bool = True,
         node_count: int = 100,
+        directed: bool = True,
         center_nodes: Optional[List[int]] = None,
-        include_node_properties: List[str] = None,
         color_property: Optional[str] = None,
+        size_property: Optional[str] = None,
+        include_node_properties: Optional[List[str]] = None,
+        rel_weight_property: Optional[str] = None,
+        notebook: bool = True,
+        px_height: int = 750,
+        theme: str = "dark",
     ) -> Any:
+        """
+        Visualize the `Graph` in an interactive graphical interface.
+        The graph will be sampled down to specified `node_count` to limit computationally expensive rendering.
+
+        Args:
+            node_count: number of nodes in the graph to be visualized
+            directed: whether or not to display relationships as directed
+            center_nodes: nodes around subgraph will be sampled, if sampling is necessary
+            color_property: node property that determines node categories for coloring. Default is to use node labels
+            size_property: node property that determines the size of nodes. Default is to compute a page rank for this
+            include_node_properties: node properties to include for mouse-over inspection
+            rel_weight_property: relationship property that determines width of relationships
+            notebook: whether or not the code is run in a notebook
+            px_height: the height of the graphic containing output the visualization
+            theme: coloring theme for the visualization. "light" or "dark"
+
+        Returns:
+            an interactive graphical visualization of the specified graph
+        """
+
+        actual_node_properties = list(chain.from_iterable(self.node_properties().to_dict().values()))
+        if (color_property is not None) and (color_property not in actual_node_properties):
+            raise ValueError(f"There is no node property '{color_property}' in graph '{self._name}'")
+
+        if size_property is not None and size_property not in actual_node_properties:
+            raise ValueError(f"There is no node property '{size_property}' in graph '{self._name}'")
+
+        if include_node_properties is not None:
+            for prop in include_node_properties:
+                if prop not in actual_node_properties:
+                    raise ValueError(f"There is no node property '{prop}' in graph '{self._name}'")
+
+        actual_rel_properties = list(chain.from_iterable(self.relationship_properties().to_dict().values()))
+        if rel_weight_property is not None and rel_weight_property not in actual_rel_properties:
+            raise ValueError(f"There is no relationship property '{rel_weight_property}' in graph '{self._name}'")
+
+        if theme not in {"light", "dark"}:
+            raise ValueError(f"Color `theme` '{theme}' is not allowed. Must be either 'light' or 'dark'")
+
         visual_graph = self._name
         if self.node_count() > node_count:
             visual_graph = str(uuid4())
@@ -256,14 +298,19 @@ def visualize(
                 custom_error=False,
             )
 
-        pr_prop = str(uuid4())
-        self._query_runner.call_procedure(
-            endpoint="gds.pageRank.mutate",
-            params=CallParameters(graph_name=visual_graph, config=dict(mutateProperty=pr_prop)),
-            custom_error=False,
-        )
+        # Make sure we always have at least a size property so that we can run `gds.graph.nodeProperties.stream`
+        if size_property is None:
+            size_property = str(uuid4())
+            self._query_runner.call_procedure(
+                endpoint="gds.pageRank.mutate",
+                params=CallParameters(graph_name=visual_graph, config=dict(mutateProperty=size_property)),
+                custom_error=False,
+            )
+            clean_up_size_prop = True
+        else:
+            clean_up_size_prop = False
 
-        node_properties = [pr_prop]
+        node_properties = [size_property]
         if include_node_properties is not None:
             node_properties.extend(include_node_properties)
 
@@ -295,11 +342,18 @@ def visualize(
             result.columns.name = None
         node_properties_df = result
 
-        relationships_df = self._query_runner.call_procedure(
-            endpoint="gds.graph.relationships.stream",
-            params=CallParameters(graph_name=visual_graph),
-            custom_error=False,
-        )
+        if rel_weight_property is None:
+            relationships_df = self._query_runner.call_procedure(
+                endpoint="gds.graph.relationships.stream",
+                params=CallParameters(graph_name=visual_graph),
+                custom_error=False,
+            )
+        else:
+            relationships_df = self._query_runner.call_procedure(
+                endpoint="gds.graph.relationshipProperty.stream",
+                params=CallParameters(graph_name=visual_graph, properties=rel_weight_property),
+                custom_error=False,
+            )
 
         # Clean up
         if visual_graph != self._name:
@@ -308,10 +362,10 @@ def visualize(
                 params=CallParameters(graph_name=visual_graph),
                 custom_error=False,
             )
-        else:
+        elif clean_up_size_prop:
             self._query_runner.call_procedure(
                 endpoint="gds.graph.nodeProperties.drop",
-                params=CallParameters(graph_name=visual_graph, nodeProperties=pr_prop),
+                params=CallParameters(graph_name=visual_graph, nodeProperties=size_property),
                 custom_error=False,
             )
 
@@ -320,19 +374,21 @@ def visualize(
         net = Network(
             notebook=True if notebook else False,
             cdn_resources="remote" if notebook else "local",
-            bgcolor="#222222",  # Dark background
-            font_color="white",
-            height="750px",  # Modify according to your screen size
+            directed=directed,
+            bgcolor="#222222" if theme == "dark" else "#F2F2F2",
+            font_color="white" if theme == "dark" else "black",
+            height=f"{px_height}px",
             width="100%",
         )
 
         if color_property is None:
-            color_map = {label: self._random_bright_color() for label in self.node_labels()}
+            color_map = {label: self._random_themed_color(theme) for label in self.node_labels()}
         else:
             color_map = {
-                prop_val: self._random_bright_color() for prop_val in node_properties_df[color_property].unique()
+                prop_val: self._random_themed_color(theme) for prop_val in node_properties_df[color_property].unique()
             }
 
+        # Add all the nodes
         for _, node in node_properties_df.iterrows():
             title = f"Node ID: {node['nodeId']}\nLabels: {node['nodeLabels']}"
             if include_node_properties is not None:
@@ -347,17 +403,22 @@ def visualize(
 
             net.add_node(
                 int(node["nodeId"]),
-                value=node[pr_prop],
+                value=node[size_property],
                 color=color,
                 title=title,
             )
 
         # Add all the relationships
-        net.add_edges(zip(relationships_df["sourceNodeId"], relationships_df["targetNodeId"]))
+        for _, rel in relationships_df.iterrows():
+            if rel_weight_property is None:
+                net.add_edge(rel["sourceNodeId"], rel["targetNodeId"], title=f"Type: {rel['relationshipType']}")
+            else:
+                title = f"Type: {rel['relationshipType']}\n{rel_weight_property} = {rel['rel_weight_property']}"
+                net.add_edge(rel["sourceNodeId"], rel["targetNodeId"], title=title, value=rel[rel_weight_property])
 
         return net.show(f"{self._name}.html")
 
     @staticmethod
-    def _random_bright_color() -> str:
-        h = random.randint(0, 255) / 255.0
-        return "#%02X%02X%02X" % tuple(map(lambda x: int(x * 255), colorsys.hls_to_rgb(h, 0.7, 1.0)))
+    def _random_themed_color(theme) -> str:
+        l = 0.7 if theme == "dark" else 0.4
+        return "#%02X%02X%02X" % tuple(map(lambda x: int(x * 255), colorsys.hls_to_rgb(random.random(), l, 1.0)))