Remove SparkR RDD examples, add dataframe examples

Author: shivaram

R/pkg/NAMESPACE

@@ -45,8 +45,6 @@ exportMethods("cache",
               "showDF",
               "sortDF",
               "take",
-              "toJSON",
-              "toRDD",
               "unionAll",
               "unpersist",
               "where",
@@ -95,14 +93,12 @@ export("cacheTable",
        "createExternalTable",
        "dropTempTable",
        "jsonFile",
-       "jsonRDD",
        "loadDF",
        "parquetFile",
        "sql",
        "table",
        "tableNames",
        "tables",
-       "toDF",
        "uncacheTable")
 
 export("sparkRSQL.init",

R/pkg/R/DataFrame.R

@@ -272,7 +272,7 @@ setMethod("names",
 setMethod("registerTempTable",
           signature(x = "DataFrame", tableName = "character"),
           function(x, tableName) {
-              callJMethod(x@sdf, "registerTempTable", tableName)
+              invisible(callJMethod(x@sdf, "registerTempTable", tableName))
           })
 
 #' insertInto

examples/src/main/r/dataframe.R

@@ -0,0 +1,54 @@
+#
+# 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(SparkR)
+
+# Initialize SparkContext and SQLContext
+sc <- sparkR.init(appName="SparkR-DataFrame-example")
+sqlContext <- sparkRSQL.init(sc)
+
+# Create a simple local data.frame
+localDF <- data.frame(name=c("John", "Smith", "Sarah"), age=c(19, 23, 18))
+
+# Convert local data frame to a SparkR DataFrame
+df <- createDataFrame(sqlContext, localDF)
+
+# Print its schema
+printSchema(df)
+# root
+#  |-- name: string (nullable = true)
+#  |-- age: double (nullable = true)
+
+# Create a DataFrame from a JSON file
+path <- file.path(Sys.getenv("SPARK_HOME"), "examples/src/main/resources/people.json")
+peopleDF <- jsonFile(sqlContext, path)
+printSchema(peopleDF)
+
+# Register this DataFrame as a table.
+registerTempTable(peopleDF, "people")
+
+# SQL statements can be run by using the sql methods provided by sqlContext
+teenagers <- sql(sqlContext, "SELECT name FROM people WHERE age >= 13 AND age <= 19")
+
+# Call collect to get a local data.frame
+teenagersLocalDF <- collect(teenagers)
+
+# Print the teenagers in our dataset 
+print(teenagersLocalDF)
+
+# Stop the SparkContext now
+sparkR.stop()