[SPARK-6807] [SparkR] Merge recent SparkR-pkg changes

R/pkg/DESCRIPTION

@@ -19,7 +19,7 @@ Collate:
     'jobj.R'
     'RDD.R'
     'pairRDD.R'
-    'SQLTypes.R'
+    'schema.R'
     'column.R'
     'group.R'
     'DataFrame.R'

R/pkg/NAMESPACE

@@ -5,6 +5,7 @@ exportMethods(
               "aggregateByKey",
               "aggregateRDD",
               "cache",
+              "cartesian",
               "checkpoint",
               "coalesce",
               "cogroup",
@@ -28,6 +29,7 @@ exportMethods(
               "fullOuterJoin",
               "glom",
               "groupByKey",
+              "intersection",
               "join",
               "keyBy",
               "keys",
@@ -52,11 +54,14 @@ exportMethods(
               "reduceByKeyLocally",
               "repartition",
               "rightOuterJoin",
+              "sampleByKey",
               "sampleRDD",
               "saveAsTextFile",
               "saveAsObjectFile",
               "sortBy",
               "sortByKey",
+              "subtract",
+              "subtractByKey",
               "sumRDD",
               "take",
               "takeOrdered",
@@ -95,6 +100,7 @@ exportClasses("DataFrame")
 exportMethods("columns",
               "distinct",
               "dtypes",
+              "except",
               "explain",
               "filter",
               "groupBy",
@@ -118,7 +124,6 @@ exportMethods("columns",
               "show",
               "showDF",
               "sortDF",
-              "subtract",
               "toJSON",
               "toRDD",
               "unionAll",
@@ -178,5 +183,14 @@ export("cacheTable",
        "toDF",
        "uncacheTable")
 
-export("print.structType",
-       "print.structField")
+export("sparkRSQL.init",
+       "sparkRHive.init")
+
+export("structField",
+       "structField.jobj",
+       "structField.character",
+       "print.structField",
+       "structType",
+       "structType.jobj",
+       "structType.structField",
+       "print.structType")

R/pkg/R/DataFrame.R

@@ -17,7 +17,7 @@
 
 # DataFrame.R - DataFrame class and methods implemented in S4 OO classes
 
-#' @include generics.R jobj.R SQLTypes.R RDD.R pairRDD.R column.R group.R
+#' @include generics.R jobj.R schema.R RDD.R pairRDD.R column.R group.R
 NULL
 
 setOldClass("jobj")
@@ -1141,29 +1141,31 @@ setMethod("intersect",
             dataFrame(intersected)
           })
 
-#' Subtract
+#' except
 #'
 #' Return a new DataFrame containing rows in this DataFrame
 #' but not in another DataFrame. This is equivalent to `EXCEPT` in SQL.
 #'
 #' @param x A Spark DataFrame
 #' @param y A Spark DataFrame
-#' @return A DataFrame containing the result of the subtract operation.
-#' @rdname subtract
+#' @return A DataFrame containing the result of the except operation.
+#' @rdname except
 #' @export
 #' @examples
 #'\dontrun{
 #' sc <- sparkR.init()
 #' sqlCtx <- sparkRSQL.init(sc)
 #' df1 <- jsonFile(sqlCtx, path)
 #' df2 <- jsonFile(sqlCtx, path2)
-#' subtractDF <- subtract(df, df2)
+#' exceptDF <- except(df, df2)
 #' }
-setMethod("subtract",
+#' @rdname except
+#' @export
+setMethod("except",
           signature(x = "DataFrame", y = "DataFrame"),
           function(x, y) {
-            subtracted <- callJMethod(x@sdf, "except", y@sdf)
-            dataFrame(subtracted)
+            excepted <- callJMethod(x@sdf, "except", y@sdf)
+            dataFrame(excepted)
           })
 
 #' Save the contents of the DataFrame to a data source

R/pkg/R/RDD.R

@@ -730,6 +730,7 @@ setMethod("take",
             index <- -1
             jrdd <- getJRDD(x)
             numPartitions <- numPartitions(x)
+            serializedModeRDD <- getSerializedMode(x)
 
             # TODO(shivaram): Collect more than one partition based on size
             # estimates similar to the scala version of `take`.
@@ -748,13 +749,14 @@ setMethod("take",
               elems <- convertJListToRList(partition,
                                            flatten = TRUE,
                                            logicalUpperBound = size,
-                                           serializedMode = getSerializedMode(x))
-              # TODO: Check if this append is O(n^2)?
+                                           serializedMode = serializedModeRDD)
+
               resList <- append(resList, elems)
             }
             resList
           })
 
+
 #' First
 #'
 #' Return the first element of an RDD
@@ -1092,21 +1094,42 @@ takeOrderedElem <- function(x, num, ascending = TRUE) {
     if (num < length(part)) {
       # R limitation: order works only on primitive types!
       ord <- order(unlist(part, recursive = FALSE), decreasing = !ascending)
-      list(part[ord[1:num]])
+      part[ord[1:num]]
     } else {
-      list(part)
+      part
     }
   }
 
-  reduceFunc <- function(elems, part) {
-    newElems <- append(elems, part)
-    # R limitation: order works only on primitive types!
-    ord <- order(unlist(newElems, recursive = FALSE), decreasing = !ascending)
-    newElems[ord[1:num]]
-  }
-
   newRdd <- mapPartitions(x, partitionFunc)
-  reduce(newRdd, reduceFunc)
+
+  resList <- list()
+  index <- -1
+  jrdd <- getJRDD(newRdd)
+  numPartitions <- numPartitions(newRdd)
+  serializedModeRDD <- getSerializedMode(newRdd)
+
+  while (TRUE) {
+    index <- index + 1
+
+    if (index >= numPartitions) {
+      ord <- order(unlist(resList, recursive = FALSE), decreasing = !ascending)
+      resList <- resList[ord[1:num]]
+      break
+    }
+
+    # a JList of byte arrays
+    partitionArr <- callJMethod(jrdd, "collectPartitions", as.list(as.integer(index)))
+    partition <- partitionArr[[1]]
+
+    # elems is capped to have at most `num` elements
+    elems <- convertJListToRList(partition,
+                                 flatten = TRUE,
+                                 logicalUpperBound = num,
+                                 serializedMode = serializedModeRDD)
+
+    resList <- append(resList, elems)
+  }
+  resList
 }
 
 #' Returns the first N elements from an RDD in ascending order.
@@ -1465,67 +1488,105 @@ setMethod("zipRDD",
               stop("Can only zip RDDs which have the same number of partitions.")
             }
 
-            if (getSerializedMode(x) != getSerializedMode(other) || 
-                getSerializedMode(x) == "byte") {
-              # Append the number of elements in each partition to that partition so that we can later
-              # check if corresponding partitions of both RDDs have the same number of elements.
-              #
-              # Note that this appending also serves the purpose of reserialization, because even if 
-              # any RDD is serialized, we need to reserialize it to make sure its partitions are encoded
-              # as a single byte array. For example, partitions of an RDD generated from partitionBy()
-              # may be encoded as multiple byte arrays.          
-              appendLength <- function(part) {
-                part[[length(part) + 1]] <- length(part) + 1
-                part
-              }
-              x <- lapplyPartition(x, appendLength)
-              other <- lapplyPartition(other, appendLength)
-            }
+            rdds <- appendPartitionLengths(x, other)
+            jrdd <- callJMethod(getJRDD(rdds[[1]]), "zip", getJRDD(rdds[[2]]))
+            # The jrdd's elements are of scala Tuple2 type. The serialized
+            # flag here is used for the elements inside the tuples.
+            rdd <- RDD(jrdd, getSerializedMode(rdds[[1]]))
 
-            zippedJRDD <- callJMethod(getJRDD(x), "zip", getJRDD(other))
-            # The zippedRDD's elements are of scala Tuple2 type. The serialized
-            # flag Here is used for the elements inside the tuples.
-            serializerMode <- getSerializedMode(x)
-            zippedRDD <- RDD(zippedJRDD, serializerMode)
+            mergePartitions(rdd, TRUE)
+          })
+
+#' Cartesian product of this RDD and another one.
+#'
+#' Return the Cartesian product of this RDD and another one, 
+#' that is, the RDD of all pairs of elements (a, b) where a 
+#' is in this and b is in other.
+#' 
+#' @param x An RDD.
+#' @param other An RDD.
+#' @return A new RDD which is the Cartesian product of these two RDDs.
+#' @examples
+#'\dontrun{
+#' sc <- sparkR.init()
+#' rdd <- parallelize(sc, 1:2)
+#' sortByKey(cartesian(rdd, rdd)) 
+#' # list(list(1, 1), list(1, 2), list(2, 1), list(2, 2))
+#'}
+#' @rdname cartesian
+#' @aliases cartesian,RDD,RDD-method
+setMethod("cartesian",
+          signature(x = "RDD", other = "RDD"),
+          function(x, other) {
+            rdds <- appendPartitionLengths(x, other)
+            jrdd <- callJMethod(getJRDD(rdds[[1]]), "cartesian", getJRDD(rdds[[2]]))
+            # The jrdd's elements are of scala Tuple2 type. The serialized
+            # flag here is used for the elements inside the tuples.
+            rdd <- RDD(jrdd, getSerializedMode(rdds[[1]]))
 
-            partitionFunc <- function(split, part) {
-              len <- length(part)
-              if (len > 0) {
-                if (serializerMode == "byte") {
-                  lengthOfValues <- part[[len]]
-                  lengthOfKeys <- part[[len - lengthOfValues]]
-                  stopifnot(len == lengthOfKeys + lengthOfValues)
-
-                  # check if corresponding partitions of both RDDs have the same number of elements.
-                  if (lengthOfKeys != lengthOfValues) {
-                    stop("Can only zip RDDs with same number of elements in each pair of corresponding partitions.")
-                  }
-
-                  if (lengthOfKeys > 1) {
-                    keys <- part[1 : (lengthOfKeys - 1)]
-                    values <- part[(lengthOfKeys + 1) : (len - 1)]                    
-                  } else {
-                    keys <- list()
-                    values <- list()
-                  }
-                } else {
-                  # Keys, values must have same length here, because this has
-                  # been validated inside the JavaRDD.zip() function.
-                  keys <- part[c(TRUE, FALSE)]
-                  values <- part[c(FALSE, TRUE)]
-                }
-                mapply(
-                    function(k, v) {
-                      list(k, v)
-                    },
-                    keys,
-                    values,
-                    SIMPLIFY = FALSE,
-                    USE.NAMES = FALSE)
-              } else {
-                part
-              }
+            mergePartitions(rdd, FALSE)
+          })
+
+#' Subtract an RDD with another RDD.
+#'
+#' Return an RDD with the elements from this that are not in other.
+#'
+#' @param x An RDD.
+#' @param other An RDD.
+#' @param numPartitions Number of the partitions in the result RDD.
+#' @return An RDD with the elements from this that are not in other.
+#' @examples
+#'\dontrun{
+#' sc <- sparkR.init()
+#' rdd1 <- parallelize(sc, list(1, 1, 2, 2, 3, 4))
+#' rdd2 <- parallelize(sc, list(2, 4))
+#' collect(subtract(rdd1, rdd2))
+#' # list(1, 1, 3)
+#'}
+#' @rdname subtract
+#' @aliases subtract,RDD
+setMethod("subtract",
+          signature(x = "RDD", other = "RDD"),
+          function(x, other, numPartitions = SparkR::numPartitions(x)) {
+            mapFunction <- function(e) { list(e, NA) }
+            rdd1 <- map(x, mapFunction)
+            rdd2 <- map(other, mapFunction)
+            keys(subtractByKey(rdd1, rdd2, numPartitions))
+          })
+
+#' Intersection of this RDD and another one.
+#'
+#' Return the intersection of this RDD and another one.
+#' The output will not contain any duplicate elements,
+#' even if the input RDDs did. Performs a hash partition
+#' across the cluster.
+#' Note that this method performs a shuffle internally.
+#'
+#' @param x An RDD.
+#' @param other An RDD.
+#' @param numPartitions The number of partitions in the result RDD.
+#' @return An RDD which is the intersection of these two RDDs.
+#' @examples
+#'\dontrun{
+#' sc <- sparkR.init()
+#' rdd1 <- parallelize(sc, list(1, 10, 2, 3, 4, 5))
+#' rdd2 <- parallelize(sc, list(1, 6, 2, 3, 7, 8))
+#' collect(sortBy(intersection(rdd1, rdd2), function(x) { x }))
+#' # list(1, 2, 3)
+#'}
+#' @rdname intersection
+#' @aliases intersection,RDD
+setMethod("intersection",
+          signature(x = "RDD", other = "RDD"),
+          function(x, other, numPartitions = SparkR::numPartitions(x)) {
+            rdd1 <- map(x, function(v) { list(v, NA) })
+            rdd2 <- map(other, function(v) { list(v, NA) })
+
+            filterFunction <- function(elem) {
+              iters <- elem[[2]]
+              all(as.vector(
+                lapply(iters, function(iter) { length(iter) > 0 }), mode = "logical"))
             }
-            
-            PipelinedRDD(zippedRDD, partitionFunc)
+
+            keys(filterRDD(cogroup(rdd1, rdd2, numPartitions = numPartitions), filterFunction))
           })