From a538745da9c49ab5d463372d6d71c6c5ac2b6816 Mon Sep 17 00:00:00 2001
From: Ralph Liu <137829296+nv-rliu@users.noreply.github.com>
Date: Thu, 15 Aug 2024 11:31:27 -0400
Subject: [PATCH] Updates to `cugraph.hypergraph` (Duplicate Col Labels Bug)
 (#4610)

cc: @rlratzel @ChuckHastings

This PR addresses failures seen in certain PRs (like [here](https://github.com/rapidsai/cugraph/actions/runs/10372270389/job/28718471674?pr=4606#step:7:5269)) due to a [recent change](https://github.com/rapidsai/cudf/pull/16514) to `cudf` that disallows selecting duplicate column labels.

---

In `hypergraph.py`, this PR modifies `_create_hyper_edges` and `_create_direct_edges` to ensure that DataFrames are being indexed by non-duplicate column values.

This is done by taking a list that includes duplicates (`fs`), and removing the non-unique values
```python
fs = list(set(fs))
```


_This part requires some attention from the author of the unit test @jnke2016_

In `test_hypergraph.py`, this PR adds the `check_like=True` arg to `assert_frame_equals` function because the ordering of the columns is different for the two DFs.

Authors:
  - Ralph Liu (https://github.com/nv-rliu)

Approvers:
  - Rick Ratzel (https://github.com/rlratzel)
  - Chuck Hastings (https://github.com/ChuckHastings)
  - Paul Taylor (https://github.com/trxcllnt)
  - Joseph Nke (https://github.com/jnke2016)

URL: https://github.com/rapidsai/cugraph/pull/4610
---
 python/cugraph/cugraph/structure/hypergraph.py        |  7 ++++---
 .../cugraph/tests/structure/test_hypergraph.py        | 11 +++++++----
 2 files changed, 11 insertions(+), 7 deletions(-)

diff --git a/python/cugraph/cugraph/structure/hypergraph.py b/python/cugraph/cugraph/structure/hypergraph.py
index add68cb6dac..b52fef4dcfc 100644
--- a/python/cugraph/cugraph/structure/hypergraph.py
+++ b/python/cugraph/cugraph/structure/hypergraph.py
@@ -440,6 +440,7 @@ def _create_hyper_edges(
     for key, col in events[columns].items():
         cat = categories.get(key, key)
         fs = [EVENTID] + ([key] if drop_edge_attrs else edge_attrs)
+        fs = list(set(fs))
         df = events[fs].dropna(subset=[key]) if dropna else events[fs]
         if len(df) == 0:
             continue
@@ -464,8 +465,7 @@ def _create_hyper_edges(
     if not drop_edge_attrs:
         columns += edge_attrs
 
-    edges = cudf.concat(edges)[columns]
-    edges.reset_index(drop=True, inplace=True)
+    edges = cudf.concat(edges, ignore_index=True)[list(set(columns))]
     return edges
 
 
@@ -546,6 +546,7 @@ def _create_direct_edges(
         for key2, col2 in events[sorted(edge_shape[key1])].items():
             cat2 = categories.get(key2, key2)
             fs = [EVENTID] + ([key1, key2] if drop_edge_attrs else edge_attrs)
+            fs = list(set(fs))
             df = events[fs].dropna(subset=[key1, key2]) if dropna else events[fs]
             if len(df) == 0:
                 continue
@@ -573,7 +574,7 @@ def _create_direct_edges(
     if not drop_edge_attrs:
         columns += edge_attrs
 
-    edges = cudf.concat(edges)[columns]
+    edges = cudf.concat(edges)[list(set(columns))]
     edges.reset_index(drop=True, inplace=True)
     return edges
 
diff --git a/python/cugraph/cugraph/tests/structure/test_hypergraph.py b/python/cugraph/cugraph/tests/structure/test_hypergraph.py
index 848f31b940f..f1dfc17a509 100644
--- a/python/cugraph/cugraph/tests/structure/test_hypergraph.py
+++ b/python/cugraph/cugraph/tests/structure/test_hypergraph.py
@@ -1,4 +1,4 @@
-# Copyright (c) 2020-2023, NVIDIA CORPORATION.
+# Copyright (c) 2020-2024, NVIDIA CORPORATION.
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
 # You may obtain a copy of the License at
@@ -171,7 +171,8 @@ def test_hyperedges(categorical_metadata):
     if categorical_metadata:
         edges = edges.astype({"edge_type": "category"})
 
-    assert_frame_equal(edges, h["edges"], check_dtype=False)
+    # check_like ignores the order of columns as long as all correct ones are present
+    assert_frame_equal(edges, h["edges"], check_dtype=False, check_like=True)
     for (k, v) in [("entities", 12), ("nodes", 15), ("edges", 12), ("events", 3)]:
         assert len(h[k]) == v
 
@@ -266,7 +267,8 @@ def test_drop_edge_attrs(categorical_metadata):
     if categorical_metadata:
         edges = edges.astype({"edge_type": "category"})
 
-    assert_frame_equal(edges, h["edges"], check_dtype=False)
+    # check_like ignores the order of columns as long as all correct ones are present
+    assert_frame_equal(edges, h["edges"], check_dtype=False, check_like=True)
 
     for (k, v) in [("entities", 9), ("nodes", 12), ("edges", 9), ("events", 3)]:
         assert len(h[k]) == v
@@ -308,7 +310,8 @@ def test_drop_edge_attrs_direct(categorical_metadata):
     if categorical_metadata:
         edges = edges.astype({"edge_type": "category"})
 
-    assert_frame_equal(edges, h["edges"], check_dtype=False)
+    # check_like ignores the order of columns as long as all correct ones are present
+    assert_frame_equal(edges, h["edges"], check_dtype=False, check_like=True)
 
     for (k, v) in [("entities", 9), ("nodes", 9), ("edges", 6), ("events", 0)]:
         assert len(h[k]) == v