algorithms -> components...

and one of the tests in algorithms beloned in test_base.py

Author: rocky

pymathics/graph/measures_and_metrics.py

@@ -110,17 +110,13 @@ class GraphDistance(_NetworkXBuiltin):
      = Infinity
 
     >> GraphDistance[g, 5]
-     = [Infinity, Infinity, Infinity, 0]
+     = {Infinity, Infinity, Infinity, Infinity, 0}
 
     >> GraphDistance[g, 3]
      = {Infinity, 1, 2, 0, 3}
 
     >> GraphDistance[g, 4]
-     = {1, 2, 1, 0, 2}
-
-    #> GraphDistance[{1 -> 2}, 3, 4]
-     : The vertex at position 2 in GraphDistance[{1 -> 2}, 3, 4] does not belong to the graph at position 1.
-     = GraphDistance[{1 -> 2}, 3, 4]
+     = {Infinity, 1, 0, 1, 1}
     """
 
     summary_text = "get path distance"

test/test_algorithms.py

@@ -0,0 +1,32 @@
+# -*- coding: utf-8 -*-
+"""
+Unit tests for pymathics.graph.base
+"""
+from test.helper import check_evaluation, evaluate, evaluate_value
+
+import pytest
+
+
+def setup_module(module):
+    """Load pymathics.graph"""
+    assert evaluate_value('LoadModule["pymathics.graph"]') == "pymathics.graph"
+    evaluate("SortList[list_] := Sort[Map[Sort, list]]")
+
+
+@pytest.mark.parametrize(
+    ("str_expr", "str_expected", "msg"),
+    [
+        (None, None, None),
+        (
+            "g = Graph[{a -> b, b <-> c, d -> c, d -> a, e <-> c, d -> b}];",
+            "Null",
+            "Intialize graph",
+        ),
+        ("Sort[DegreeCentrality[g]]", "{2, 2, 3, 4, 5}", None),
+        ('Sort[DegreeCentrality[g, "In"]]', "{0, 1, 1, 3, 3}", None),
+        ('Sort[DegreeCentrality[g, "Out"]]', "{1, 1, 1, 2, 3}", None),
+        (None, None, None),
+    ],
+)
+def test_degree_centrality(str_expr, str_expected, msg):
+    check_evaluation(str_expr, str_expected, failure_message=msg)

test/test_base.py

@@ -0,0 +1,22 @@
+# -*- coding: utf-8 -*-
+"""
+Unit tests for pymathics.graph.components
+"""
+from test.helper import check_evaluation, evaluate, evaluate_value
+
+
+def setup_module(module):
+    """Load pymathics.graph"""
+    assert evaluate_value('LoadModule["pymathics.graph"]') == "pymathics.graph"
+    evaluate("SortList[list_] := Sort[Map[Sort, list]]")
+
+
+def test_connected_components():
+    for str_expr, str_expected in [
+        ("PlanarGraphQ[Graph[{}]]", "False"),
+        ("g = Graph[{1 -> 2, 2 -> 3, 3 <-> 4}];", "Null"),
+        ("SortList[ConnectedComponents[g]]", "{{1}, {2}, {3, 4}}"),
+        ("g = Graph[{1 -> 2, 2 -> 3, 3 -> 1}];", "Null"),
+        ("SortList[ConnectedComponents[g]]", "{{1, 2, 3}}"),
+    ]:
+        check_evaluation(str_expr, str_expected)

test/test_components.py

@@ -0,0 +1,43 @@
+"""
+Unit tests for pymathics.graph.measures_and_metrics
+"""
+
+from test.helper import check_evaluation
+
+
+def test_graph_distance():
+    for str_expr, str_expected, mess in [
+        (
+            "GraphDistance[{1 <-> 2, 2 <-> 3, 3 <-> 4, 2 <-> 4, 4 -> 5}, 1, 5]",
+            "3",
+            None,
+        ),
+        ("GraphDistance[{1 <-> 2, 2 <-> 3, 3 <-> 4, 4 -> 2, 4 -> 5}, 1, 5]", "4", None),
+        (
+            "GraphDistance[{1 <-> 2, 2 <-> 3, 4 -> 3, 4 -> 2, 4 -> 5}, 1, 5]",
+            "Infinity",
+            None,
+        ),
+        (
+            "Sort[GraphDistance[{1 <-> 2, 2 <-> 3, 3 <-> 4, 2 <-> 4, 4 -> 5}, 3]]",
+            "{0, 1, 1, 2, 2}",
+            None,
+        ),
+        (
+            "GraphDistance[{}, 1, 1]",
+            "GraphDistance[{}, 1, 1]",
+            [
+                "The vertex at position 2 in GraphDistance[{}, 1, 1] does not belong to "
+                "the graph at position 1."
+            ],
+        ),
+        (
+            "GraphDistance[{1 -> 2}, 3, 4]",
+            "GraphDistance[{1 -> 2}, 3, 4]",
+            [
+                "The vertex at position 2 in GraphDistance[{1 -> 2}, 3, 4] does not belong "
+                "to the graph at position 1."
+            ],
+        ),
+    ]:
+        check_evaluation(str_expr, str_expected, expected_messages=mess)