Update extrema bounding method for compute="eccentricities" parameter (#5409)

Fixes #5402

* update extrema bounding method

* update style

* update style 2

* update style 3

* update style 4

* update documentation and add a test

* Rm test encapsulation.

Co-authored-by: Ross Barnowski <rossbar@berkeley.edu>

2 files changed, 17 insertions, 9 deletions

diff --git a/networkx/algorithms/distance_measures.py b/networkx/algorithms/distance_measures.py
index ef665dc7..7a1ce3d6 100644
--- a/networkx/algorithms/distance_measures.py
+++ b/networkx/algorithms/distance_measures.py
@@ -30,20 +30,23 @@ def extrema_bounding(G, compute="diameter"):
     compute : string denoting the requesting metric
        "diameter" for the maximal eccentricity value,
        "radius" for the minimal eccentricity value,
-       "periphery" for the set of nodes with eccentricity equal to the diameter
-       "center" for the set of nodes with eccentricity equal to the radius
+       "periphery" for the set of nodes with eccentricity equal to the diameter,
+       "center" for the set of nodes with eccentricity equal to the radius,
+       "eccentricities" for the maximum distance from each node to all other nodes in G
 
     Returns
     -------
     value : value of the requested metric
        int for "diameter" and "radius" or
-       list of nodes for "center" and "periphery"
+       list of nodes for "center" and "periphery" or
+       dictionary of eccentricity values keyed by node for "eccentricities"
 
     Raises
     ------
     NetworkXError
         If the graph consists of multiple components
-
+    ValueError
+        If `compute` is not one of "diameter", "radius", "periphery", "center", or "eccentricities".
     Notes
     -----
     This algorithm was proposed in the following papers:
@@ -125,14 +128,12 @@ def extrema_bounding(G, compute="diameter"):
                 for i in candidates
                 if ecc_upper[i] <= maxlower and 2 * ecc_lower[i] >= maxupper
             }
-
         elif compute == "radius":
             ruled_out = {
                 i
                 for i in candidates
                 if ecc_lower[i] >= minupper and ecc_upper[i] + 1 <= 2 * minlower
             }
-
         elif compute == "periphery":
             ruled_out = {
                 i
@@ -140,7 +141,6 @@ def extrema_bounding(G, compute="diameter"):
                 if ecc_upper[i] < maxlower
                 and (maxlower == maxupper or ecc_lower[i] > maxupper)
             }
-
         elif compute == "center":
             ruled_out = {
                 i
@@ -148,9 +148,11 @@ def extrema_bounding(G, compute="diameter"):
                 if ecc_lower[i] > minupper
                 and (minlower == minupper or ecc_upper[i] + 1 < 2 * minlower)
             }
-
         elif compute == "eccentricities":
-            ruled_out = {}
+            ruled_out = set()
+        else:
+            msg = "compute must be one of 'diameter', 'radius', 'periphery', 'center', 'eccentricities'"
+            raise ValueError(msg)
 
         ruled_out.update(i for i in candidates if ecc_lower[i] == ecc_upper[i])
         candidates -= ruled_out
diff --git a/networkx/algorithms/tests/test_distance_measures.py b/networkx/algorithms/tests/test_distance_measures.py
index f36d58a3..e3c825e5 100644
--- a/networkx/algorithms/tests/test_distance_measures.py
+++ b/networkx/algorithms/tests/test_distance_measures.py
@@ -7,6 +7,12 @@ import networkx as nx
 from networkx import convert_node_labels_to_integers as cnlti
 
 
+def test_extrema_bounding_invalid_compute_kwarg():
+    G = nx.path_graph(3)
+    with pytest.raises(ValueError, match="compute must be one of"):
+        nx.extrema_bounding(G, compute="spam")
+
+
 class TestDistance:
     def setup_method(self):
         G = cnlti(nx.grid_2d_graph(4, 4), first_label=1, ordering="sorted")