Minor feats

.gitignore

@@ -86,7 +86,7 @@ ipython_config.py
 # pyenv
 #   For a library or package, you might want to ignore these files since the code is
 #   intended to run in multiple environments; otherwise, check them in:
-# .python-version
+.python-version
 
 # pipenv
 #   According to pypa/pipenv#598, it is recommended to include Pipfile.lock in version control.
@@ -148,4 +148,4 @@ tutorials/test.*
 
 # airspeed velocity files
 benchmarks/html/
-benchmarks/results/
+benchmarks/results/

tests/classes/test_function.py

@@ -4,6 +4,16 @@
 from xgi.exception import IDNotFound, XGIError
 
 
+def test_num_edges_order(edgelist2):
+
+    H = xgi.Hypergraph(edgelist2)
+
+    assert xgi.num_edges_order(H, 0) == 0
+    assert xgi.num_edges_order(H, 1) == 2
+    assert xgi.num_edges_order(H, 2) == 1
+    assert xgi.num_edges_order(H) == 3
+
+
 def test_max_edge_order(edgelist1, edgelist4, edgelist5):
     H0 = xgi.empty_hypergraph()
     H1 = xgi.empty_hypergraph()
@@ -59,6 +69,8 @@ def test_degree_counts(edgelist1, edgelist2, edgelist3):
     assert xgi.degree_counts(H2) == [0, 5, 1]
     assert xgi.degree_counts(H3) == [0, 4, 2]
 
+    assert xgi.degree_counts(H1, order=2) == [2,6]
+
 
 def test_degree_histogram(edgelist1, edgelist2, edgelist3):
     H1 = xgi.Hypergraph(edgelist1)

xgi/classes/function.py

@@ -8,6 +8,7 @@
 from .hypergraph import Hypergraph
 
 __all__ = [
+    "num_edges_order",
     "max_edge_order",
     "is_possible_order",
     "is_uniform",
@@ -27,6 +28,23 @@
     "convert_labels_to_integers",
 ]
 
+def num_edges_order(H, d=None):
+    """The number of edges of order d.
+
+    Parameters
+    ----------
+    H : Hypergraph
+        The hypergraph of interest.
+
+    d : int | None, optional
+        The order of edges to count. If None (default), counts
+        for all orders. 
+    """
+
+    if d is not None: 
+        return len(H.edges.filterby("order", d))
+    else: 
+        return H.num_edges
 
 def max_edge_order(H):
     """The maximum order of edges in the hypergraph.
@@ -149,13 +167,16 @@ def edge_neighborhood(H, n, include_self=False):
         return [H.edges.members(e) - {n} for e in H.nodes.memberships(n)]
 
 
-def degree_counts(H):
+def degree_counts(H, order=None):
     """Returns a list of the frequency of each degree value.
 
     Parameters
     ----------
     H : Hypergraph object
         The hypergraph of interest
+    order: int, optional
+        Order of edges to take into account. If None (default), 
+        consider all edges.
 
     Returns
     -------
@@ -177,7 +198,7 @@ def degree_counts(H):
     [0, 3, 1]
 
     """
-    counts = Counter(H.degree().values())
+    counts = Counter(H.degree(order=order).values())
     return [counts.get(i, 0) for i in range(max(counts) + 1)]