From 2c8fade3d7da2ae934d06d55494a3896a0591f9b Mon Sep 17 00:00:00 2001
From: Han Fei <hanfei19910905@gmail.com>
Date: Mon, 19 Aug 2024 17:06:24 +0200
Subject: [PATCH] fix bug in mann whitney u test

---
 .../AggregateFunctionMannWhitney.cpp          |  2 +-
 .../01561_mann_whitney_scipy.python           | 22 ++++++++++++++++++-
 2 files changed, 22 insertions(+), 2 deletions(-)

diff --git a/src/AggregateFunctions/AggregateFunctionMannWhitney.cpp b/src/AggregateFunctions/AggregateFunctionMannWhitney.cpp
index fa90846650d..ecd848f5af3 100644
--- a/src/AggregateFunctions/AggregateFunctionMannWhitney.cpp
+++ b/src/AggregateFunctions/AggregateFunctionMannWhitney.cpp
@@ -114,7 +114,7 @@ private:
             {
                 if (ind < first.size())
                     return first[ind];
-                return second[ind % first.size()];
+                return second[ind - first.size()];
             }
 
             size_t size() const
diff --git a/tests/queries/0_stateless/01561_mann_whitney_scipy.python b/tests/queries/0_stateless/01561_mann_whitney_scipy.python
index 4713120287d..a15ab7a41d9 100644
--- a/tests/queries/0_stateless/01561_mann_whitney_scipy.python
+++ b/tests/queries/0_stateless/01561_mann_whitney_scipy.python
@@ -17,9 +17,20 @@ def test_and_check(name, a, b, t_stat, p_value):
     client.query(
         "CREATE TABLE mann_whitney (left Float64, right UInt8) ENGINE = Memory;"
     )
+    #client.query(
+    #    "INSERT INTO mann_whitney VALUES {};".format(
+    #        ", ".join(["({},{}), ({},{})".format(i, 0, j, 1) for i, j in zip(a, b)])
+    #    )
+    #)
     client.query(
         "INSERT INTO mann_whitney VALUES {};".format(
-            ", ".join(["({},{}), ({},{})".format(i, 0, j, 1) for i, j in zip(a, b)])
+            ", ".join(["({},{})".format(i, 0) for i in a])
+        )
+    )
+
+    client.query(
+        "INSERT INTO mann_whitney VALUES {};".format(
+            ", ".join(["({},{})".format(i, 1) for i in b])
         )
     )
 
@@ -59,6 +70,15 @@ def test_mann_whitney():
     test_and_check("mannWhitneyUTest('greater')", rvs1, rvs2, s, p)
 
 
+def test_mann_whitney_skew():
+    rvs1 = [1]
+    rvs2 = [0,2,4]
+    s, p = stats.mannwhitneyu(rvs1, rvs2, alternative="two-sided")
+    test_and_check("mannWhitneyUTest", rvs1, rvs2, s, p)
+    test_and_check("mannWhitneyUTest('two-sided')", rvs1, rvs2, s, p)
+
+
 if __name__ == "__main__":
     test_mann_whitney()
+    test_mann_whitney_skew()
     print("Ok.")