[SPARK-9201] [ML] Initial integration of MLlib + SparkR using RFormula

This exposes the SparkR:::glm() and SparkR:::predict() APIs. It was necessary to change RFormula to silently drop the label column if it was missing from the input dataset, which is kind of a hack but necessary to integrate with the Pipeline API.

The umbrella design doc for MLlib + SparkR integration can be viewed here: https://docs.google.com/document/d/10NZNSEurN2EdWM31uFYsgayIPfCFHiuIu3pCWrUmP_c/edit

mengxr

Author: Eric Liang <ekl@databricks.com>

Closes #7483 from ericl/spark-8774 and squashes the following commits:

3dfac0c [Eric Liang] update
17ef516 [Eric Liang] more comments
1753a0f [Eric Liang] make glm generic
b0f50f8 [Eric Liang] equivalence test
550d56d [Eric Liang] export methods
c015697 [Eric Liang] second pass
117949a [Eric Liang] comments
5afbc67 [Eric Liang] test label columns
6b7f15f [Eric Liang] Fri Jul 17 14:20:22 PDT 2015
3a63ae5 [Eric Liang] Fri Jul 17 13:41:52 PDT 2015
ce61367 [Eric Liang] Fri Jul 17 13:41:17 PDT 2015
0299c59 [Eric Liang] Fri Jul 17 13:40:32 PDT 2015
e37603f [Eric Liang] Fri Jul 17 12:15:03 PDT 2015
d417d0c [Eric Liang] Merge remote-tracking branch 'upstream/master' into spark-8774
29a2ce7 [Eric Liang] Merge branch 'spark-8774-1' into spark-8774
d1959d2 [Eric Liang] clarify comment
2db68aa [Eric Liang] second round of comments
dc3c943 [Eric Liang] address comments
5765ec6 [Eric Liang] fix style checks
1f361b0 [Eric Liang] doc
d33211b [Eric Liang] r support
fb0826b [Eric Liang] [SPARK-8774] Add R model formula with basic support as a transformer

1 files changed, 42 insertions, 0 deletions

diff --git a/R/pkg/inst/tests/test_mllib.R b/R/pkg/inst/tests/test_mllib.R
new file mode 100644
index 0000000000..a492763344
--- /dev/null
+++ b/R/pkg/inst/tests/test_mllib.R
@@ -0,0 +1,42 @@
+#
+# Licensed to the Apache Software Foundation (ASF) under one or more
+# contributor license agreements.  See the NOTICE file distributed with
+# this work for additional information regarding copyright ownership.
+# The ASF licenses this file to You 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
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+library(testthat)
+
+context("MLlib functions")
+
+# Tests for MLlib functions in SparkR
+
+sc <- sparkR.init()
+
+sqlContext <- sparkRSQL.init(sc)
+
+test_that("glm and predict", {
+  training <- createDataFrame(sqlContext, iris)
+  test <- select(training, "Sepal_Length")
+  model <- glm(Sepal_Width ~ Sepal_Length, training, family = "gaussian")
+  prediction <- predict(model, test)
+  expect_equal(typeof(take(select(prediction, "prediction"), 1)$prediction), "double")
+})
+
+test_that("predictions match with native glm", {
+  training <- createDataFrame(sqlContext, iris)
+  model <- glm(Sepal_Width ~ Sepal_Length, data = training)
+  vals <- collect(select(predict(model, training), "prediction"))
+  rVals <- predict(glm(Sepal.Width ~ Sepal.Length, data = iris), iris)
+  expect_true(all(abs(rVals - vals) < 1e-9), rVals - vals)
+})