From 515ebf36c4c05255d91a511ce66b412a3054f30a Mon Sep 17 00:00:00 2001
From: Toru Seo <34780089+toruseo@users.noreply.github.com>
Date: Mon, 16 Sep 2024 19:18:24 +0900
Subject: [PATCH 1/2] add `get_shortest_path_distance_between_all_nodes`

---
 uxsim/uxsim.py | 32 ++++++++++++++++++++++++++++++++
 1 file changed, 32 insertions(+)

diff --git a/uxsim/uxsim.py b/uxsim/uxsim.py
index 12051e1..37b6d15 100644
--- a/uxsim/uxsim.py
+++ b/uxsim/uxsim.py
@@ -2208,6 +2208,38 @@ def get_nodes_in_area(W, x, y, r):
             if (node.x-x)**2 + (node.y-y)**2 < r**2:
                 nodes.append(node)
         return nodes
+    
+    def get_distance_between_all_nodes(W, return_matrix=False):
+        """
+        Get the shortest distances (in meters) between all node pairs based on link lengths.
+
+        Parameters
+        ----------
+        return_matrix : bool, optional
+            Whether to return the distance matrix as a numpy array. Default is False.
+
+        Returns
+        -------
+        dict or numpy array
+            Returns a dictionary of distances between nodes whose key is node if `return_matrix` is False.
+            Returns a numpy array of distances between nodes whose index is node.id if `return_matrix` is True.
+        """
+        num_nodes = len(W.NODES)
+        distances = np.full((num_nodes, num_nodes), np.inf)  # Initialize with infinity
+
+        # Fill in the distances based on the link lengths
+        for link in W.LINKS:
+            i = link.start_node.id
+            j = link.end_node.id
+            distances[i, j] = min(distances[i, j], link.length)
+
+        # Use Dijkstra algorithm to compute shortest distances
+        distances = *dijkstra(csr_matrix(distances), directed=True, return_predecessors=False),
+
+        if return_matrix == True:
+            return distances
+        else:
+            raise NotImplementedError("return_matrix=True is not implemented yet.")#TODO
 
     def load_scenario_from_csv(W, fname_node, fname_link, fname_demand, tmax=None):
         """

From 5239708bda67a401a36a348a0df1a8a701122086 Mon Sep 17 00:00:00 2001
From: Toru Seo <34780089+toruseo@users.noreply.github.com>
Date: Mon, 16 Sep 2024 19:21:15 +0900
Subject: [PATCH 2/2] correct name
 `get_shortest_path_distance_between_all_nodes`

---
 uxsim/uxsim.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/uxsim/uxsim.py b/uxsim/uxsim.py
index 37b6d15..b6025b6 100644
--- a/uxsim/uxsim.py
+++ b/uxsim/uxsim.py
@@ -2209,7 +2209,7 @@ def get_nodes_in_area(W, x, y, r):
                 nodes.append(node)
         return nodes
     
-    def get_distance_between_all_nodes(W, return_matrix=False):
+    def get_shortest_path_distance_between_all_nodes(W, return_matrix=False):
         """
         Get the shortest distances (in meters) between all node pairs based on link lengths.