diff options
| author | Burak Yavuz <brkyvz@gmail.com> | 2015-05-01 13:29:17 -0700 |
|---|---|---|
| committer | Reynold Xin <rxin@databricks.com> | 2015-05-01 13:29:17 -0700 |
| commit | 4dc8d74491b101a794cf8d386d8c5ebc6019b75f (patch) | |
| tree | 01733e92623635c80a0e3d7b50869b742f3f82a1 /python/pyspark/sql/tests.py | |
| parent | 7b5dd3e3c0030087eea5a8224789352c03717c1d (diff) | |
| download | spark-4dc8d74491b101a794cf8d386d8c5ebc6019b75f.tar.gz spark-4dc8d74491b101a794cf8d386d8c5ebc6019b75f.tar.bz2 spark-4dc8d74491b101a794cf8d386d8c5ebc6019b75f.zip | |
[SPARK-7240][SQL] Single pass covariance calculation for dataframes
Added the calculation of covariance between two columns to DataFrames.
cc mengxr rxin
Author: Burak Yavuz <brkyvz@gmail.com>
Closes #5825 from brkyvz/df-cov and squashes the following commits:
cb18046 [Burak Yavuz] changed to sample covariance
f2e862b [Burak Yavuz] fixed failed test
51e39b8 [Burak Yavuz] moved implementation
0c6a759 [Burak Yavuz] addressed math comments
8456eca [Burak Yavuz] fix pyStyle3
aa2ad29 [Burak Yavuz] fix pyStyle2
4e97a50 [Burak Yavuz] Merge branch 'master' of github.com:apache/spark into df-cov
e3b0b85 [Burak Yavuz] addressed comments v0.1
a7115f1 [Burak Yavuz] fix python style
7dc6dbc [Burak Yavuz] reorder imports
408cb77 [Burak Yavuz] initial commit
Diffstat (limited to 'python/pyspark/sql/tests.py')
| -rw-r--r-- | python/pyspark/sql/tests.py | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/python/pyspark/sql/tests.py b/python/pyspark/sql/tests.py index 5640bb5ea2..44c8b6a1aa 100644 --- a/python/pyspark/sql/tests.py +++ b/python/pyspark/sql/tests.py @@ -387,6 +387,11 @@ class SQLTests(ReusedPySparkTestCase): self.assertTrue(95 < g.agg(functions.approxCountDistinct(df.key)).first()[0]) self.assertEqual(100, g.agg(functions.countDistinct(df.value)).first()[0]) + def test_cov(self): + df = self.sc.parallelize([Row(a=i, b=2 * i) for i in range(10)]).toDF() + cov = df.stat.cov("a", "b") + self.assertTrue(abs(cov - 55.0 / 3) < 1e-6) + def test_math_functions(self): df = self.sc.parallelize([Row(a=i, b=2 * i) for i in range(10)]).toDF() from pyspark.sql import mathfunctions as functions |