http://git-wip-us.apache.org/repos/asf/spark/blob/2fe0a1aa/R/pkg/NAMESPACE ---------------------------------------------------------------------- diff --git a/R/pkg/NAMESPACE b/R/pkg/NAMESPACE new file mode 100644 index 0000000..a354cdc --- /dev/null +++ b/R/pkg/NAMESPACE @@ -0,0 +1,182 @@ +#exportPattern("^[[:alpha:]]+") +exportClasses("RDD") +exportClasses("Broadcast") +exportMethods( + "aggregateByKey", + "aggregateRDD", + "cache", + "checkpoint", + "coalesce", + "cogroup", + "collect", + "collectAsMap", + "collectPartition", + "combineByKey", + "count", + "countByKey", + "countByValue", + "distinct", + "Filter", + "filterRDD", + "first", + "flatMap", + "flatMapValues", + "fold", + "foldByKey", + "foreach", + "foreachPartition", + "fullOuterJoin", + "glom", + "groupByKey", + "join", + "keyBy", + "keys", + "length", + "lapply", + "lapplyPartition", + "lapplyPartitionsWithIndex", + "leftOuterJoin", + "lookup", + "map", + "mapPartitions", + "mapPartitionsWithIndex", + "mapValues", + "maximum", + "minimum", + "numPartitions", + "partitionBy", + "persist", + "pipeRDD", + "reduce", + "reduceByKey", + "reduceByKeyLocally", + "repartition", + "rightOuterJoin", + "sampleRDD", + "saveAsTextFile", + "saveAsObjectFile", + "sortBy", + "sortByKey", + "sumRDD", + "take", + "takeOrdered", + "takeSample", + "top", + "unionRDD", + "unpersist", + "value", + "values", + "zipRDD", + "zipWithIndex", + "zipWithUniqueId" + ) + +# S3 methods exported +export( + "textFile", + "objectFile", + "parallelize", + "hashCode", + "includePackage", + "broadcast", + "setBroadcastValue", + "setCheckpointDir" + ) +export("sparkR.init") +export("sparkR.stop") +export("print.jobj") +useDynLib(SparkR, stringHashCode) +importFrom(methods, setGeneric, setMethod, setOldClass) + +# SparkRSQL + +exportClasses("DataFrame") + +exportMethods("columns", + "distinct", + "dtypes", + "explain", + "filter", + "groupBy", + "head", + "insertInto", + "intersect", + "isLocal", + "limit", + "orderBy", + "names", + "printSchema", + "registerTempTable", + "repartition", + "sampleDF", + "saveAsParquetFile", + "saveAsTable", + "saveDF", + "schema", + "select", + "selectExpr", + "show", + "showDF", + "sortDF", + "subtract", + "toJSON", + "toRDD", + "unionAll", + "where", + "withColumn", + "withColumnRenamed") + +exportClasses("Column") + +exportMethods("abs", + "alias", + "approxCountDistinct", + "asc", + "avg", + "cast", + "contains", + "countDistinct", + "desc", + "endsWith", + "getField", + "getItem", + "isNotNull", + "isNull", + "last", + "like", + "lower", + "max", + "mean", + "min", + "rlike", + "sqrt", + "startsWith", + "substr", + "sum", + "sumDistinct", + "upper") + +exportClasses("GroupedData") +exportMethods("agg") + +export("sparkRSQL.init", + "sparkRHive.init") + +export("cacheTable", + "clearCache", + "createDataFrame", + "createExternalTable", + "dropTempTable", + "jsonFile", + "jsonRDD", + "loadDF", + "parquetFile", + "sql", + "table", + "tableNames", + "tables", + "toDF", + "uncacheTable") + +export("print.structType", + "print.structField")
http://git-wip-us.apache.org/repos/asf/spark/blob/2fe0a1aa/R/pkg/R/DataFrame.R ---------------------------------------------------------------------- diff --git a/R/pkg/R/DataFrame.R b/R/pkg/R/DataFrame.R new file mode 100644 index 0000000..feafd56 --- /dev/null +++ b/R/pkg/R/DataFrame.R @@ -0,0 +1,1270 @@ +# +# 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. +# + +# DataFrame.R - DataFrame class and methods implemented in S4 OO classes + +#' @include jobj.R SQLTypes.R RDD.R pairRDD.R column.R group.R +NULL + +setOldClass("jobj") + +#' @title S4 class that represents a DataFrame +#' @description DataFrames can be created using functions like +#' \code{jsonFile}, \code{table} etc. +#' @rdname DataFrame +#' @seealso jsonFile, table +#' +#' @param env An R environment that stores bookkeeping states of the DataFrame +#' @param sdf A Java object reference to the backing Scala DataFrame +#' @export +setClass("DataFrame", + slots = list(env = "environment", + sdf = "jobj")) + +setMethod("initialize", "DataFrame", function(.Object, sdf, isCached) { + .Object@env <- new.env() + .Object@env$isCached <- isCached + + .Object@sdf <- sdf + .Object +}) + +#' @rdname DataFrame +#' @export +dataFrame <- function(sdf, isCached = FALSE) { + new("DataFrame", sdf, isCached) +} + +############################ DataFrame Methods ############################################## + +#' Print Schema of a DataFrame +#' +#' Prints out the schema in tree format +#' +#' @param x A SparkSQL DataFrame +#' +#' @rdname printSchema +#' @export +#' @examples +#'\dontrun{ +#' sc <- sparkR.init() +#' sqlCtx <- sparkRSQL.init(sc) +#' path <- "path/to/file.json" +#' df <- jsonFile(sqlCtx, path) +#' printSchema(df) +#'} +setMethod("printSchema", + signature(x = "DataFrame"), + function(x) { + schemaString <- callJMethod(schema(x)$jobj, "treeString") + cat(schemaString) + }) + +#' Get schema object +#' +#' Returns the schema of this DataFrame as a structType object. +#' +#' @param x A SparkSQL DataFrame +#' +#' @rdname schema +#' @export +#' @examples +#'\dontrun{ +#' sc <- sparkR.init() +#' sqlCtx <- sparkRSQL.init(sc) +#' path <- "path/to/file.json" +#' df <- jsonFile(sqlCtx, path) +#' dfSchema <- schema(df) +#'} +setMethod("schema", + signature(x = "DataFrame"), + function(x) { + structType(callJMethod(x@sdf, "schema")) + }) + +#' Explain +#' +#' Print the logical and physical Catalyst plans to the console for debugging. +#' +#' @param x A SparkSQL DataFrame +#' @param extended Logical. If extended is False, explain() only prints the physical plan. +#' @rdname explain +#' @export +#' @examples +#'\dontrun{ +#' sc <- sparkR.init() +#' sqlCtx <- sparkRSQL.init(sc) +#' path <- "path/to/file.json" +#' df <- jsonFile(sqlCtx, path) +#' explain(df, TRUE) +#'} +setMethod("explain", + signature(x = "DataFrame"), + function(x, extended = FALSE) { + queryExec <- callJMethod(x@sdf, "queryExecution") + if (extended) { + cat(callJMethod(queryExec, "toString")) + } else { + execPlan <- callJMethod(queryExec, "executedPlan") + cat(callJMethod(execPlan, "toString")) + } + }) + +#' isLocal +#' +#' Returns True if the `collect` and `take` methods can be run locally +#' (without any Spark executors). +#' +#' @param x A SparkSQL DataFrame +#' +#' @rdname isLocal +#' @export +#' @examples +#'\dontrun{ +#' sc <- sparkR.init() +#' sqlCtx <- sparkRSQL.init(sc) +#' path <- "path/to/file.json" +#' df <- jsonFile(sqlCtx, path) +#' isLocal(df) +#'} +setMethod("isLocal", + signature(x = "DataFrame"), + function(x) { + callJMethod(x@sdf, "isLocal") + }) + +#' ShowDF +#' +#' Print the first numRows rows of a DataFrame +#' +#' @param x A SparkSQL DataFrame +#' @param numRows The number of rows to print. Defaults to 20. +#' +#' @rdname showDF +#' @export +#' @examples +#'\dontrun{ +#' sc <- sparkR.init() +#' sqlCtx <- sparkRSQL.init(sc) +#' path <- "path/to/file.json" +#' df <- jsonFile(sqlCtx, path) +#' showDF(df) +#'} +setMethod("showDF", + signature(x = "DataFrame"), + function(x, numRows = 20) { + cat(callJMethod(x@sdf, "showString", numToInt(numRows)), "\n") + }) + +#' show +#' +#' Print the DataFrame column names and types +#' +#' @param x A SparkSQL DataFrame +#' +#' @rdname show +#' @export +#' @examples +#'\dontrun{ +#' sc <- sparkR.init() +#' sqlCtx <- sparkRSQL.init(sc) +#' path <- "path/to/file.json" +#' df <- jsonFile(sqlCtx, path) +#' show(df) +#'} +setMethod("show", "DataFrame", + function(object) { + cols <- lapply(dtypes(object), function(l) { + paste(l, collapse = ":") + }) + s <- paste(cols, collapse = ", ") + cat(paste("DataFrame[", s, "]\n", sep = "")) + }) + +#' DataTypes +#' +#' Return all column names and their data types as a list +#' +#' @param x A SparkSQL DataFrame +#' +#' @rdname dtypes +#' @export +#' @examples +#'\dontrun{ +#' sc <- sparkR.init() +#' sqlCtx <- sparkRSQL.init(sc) +#' path <- "path/to/file.json" +#' df <- jsonFile(sqlCtx, path) +#' dtypes(df) +#'} +setMethod("dtypes", + signature(x = "DataFrame"), + function(x) { + lapply(schema(x)$fields(), function(f) { + c(f$name(), f$dataType.simpleString()) + }) + }) + +#' Column names +#' +#' Return all column names as a list +#' +#' @param x A SparkSQL DataFrame +#' +#' @rdname columns +#' @export +#' @examples +#'\dontrun{ +#' sc <- sparkR.init() +#' sqlCtx <- sparkRSQL.init(sc) +#' path <- "path/to/file.json" +#' df <- jsonFile(sqlCtx, path) +#' columns(df) +#'} +setMethod("columns", + signature(x = "DataFrame"), + function(x) { + sapply(schema(x)$fields(), function(f) { + f$name() + }) + }) + +#' @rdname columns +#' @export +setMethod("names", + signature(x = "DataFrame"), + function(x) { + columns(x) + }) + +#' Register Temporary Table +#' +#' Registers a DataFrame as a Temporary Table in the SQLContext +#' +#' @param x A SparkSQL DataFrame +#' @param tableName A character vector containing the name of the table +#' +#' @rdname registerTempTable +#' @export +#' @examples +#'\dontrun{ +#' sc <- sparkR.init() +#' sqlCtx <- sparkRSQL.init(sc) +#' path <- "path/to/file.json" +#' df <- jsonFile(sqlCtx, path) +#' registerTempTable(df, "json_df") +#' new_df <- sql(sqlCtx, "SELECT * FROM json_df") +#'} +setMethod("registerTempTable", + signature(x = "DataFrame", tableName = "character"), + function(x, tableName) { + callJMethod(x@sdf, "registerTempTable", tableName) + }) + +#' insertInto +#' +#' Insert the contents of a DataFrame into a table registered in the current SQL Context. +#' +#' @param x A SparkSQL DataFrame +#' @param tableName A character vector containing the name of the table +#' @param overwrite A logical argument indicating whether or not to overwrite +#' the existing rows in the table. +#' +#' @rdname insertInto +#' @export +#' @examples +#'\dontrun{ +#' sc <- sparkR.init() +#' sqlCtx <- sparkRSQL.init(sc) +#' df <- loadDF(sqlCtx, path, "parquet") +#' df2 <- loadDF(sqlCtx, path2, "parquet") +#' registerTempTable(df, "table1") +#' insertInto(df2, "table1", overwrite = TRUE) +#'} +setMethod("insertInto", + signature(x = "DataFrame", tableName = "character"), + function(x, tableName, overwrite = FALSE) { + callJMethod(x@sdf, "insertInto", tableName, overwrite) + }) + +#' Cache +#' +#' Persist with the default storage level (MEMORY_ONLY). +#' +#' @param x A SparkSQL DataFrame +#' +#' @rdname cache-methods +#' @export +#' @examples +#'\dontrun{ +#' sc <- sparkR.init() +#' sqlCtx <- sparkRSQL.init(sc) +#' path <- "path/to/file.json" +#' df <- jsonFile(sqlCtx, path) +#' cache(df) +#'} +setMethod("cache", + signature(x = "DataFrame"), + function(x) { + cached <- callJMethod(x@sdf, "cache") + x@env$isCached <- TRUE + x + }) + +#' Persist +#' +#' Persist this DataFrame with the specified storage level. For details of the +#' supported storage levels, refer to +#' http://spark.apache.org/docs/latest/programming-guide.html#rdd-persistence. +#' +#' @param x The DataFrame to persist +#' @rdname persist +#' @export +#' @examples +#'\dontrun{ +#' sc <- sparkR.init() +#' sqlCtx <- sparkRSQL.init(sc) +#' path <- "path/to/file.json" +#' df <- jsonFile(sqlCtx, path) +#' persist(df, "MEMORY_AND_DISK") +#'} +setMethod("persist", + signature(x = "DataFrame", newLevel = "character"), + function(x, newLevel) { + callJMethod(x@sdf, "persist", getStorageLevel(newLevel)) + x@env$isCached <- TRUE + x + }) + +#' Unpersist +#' +#' Mark this DataFrame as non-persistent, and remove all blocks for it from memory and +#' disk. +#' +#' @param x The DataFrame to unpersist +#' @param blocking Whether to block until all blocks are deleted +#' @rdname unpersist-methods +#' @export +#' @examples +#'\dontrun{ +#' sc <- sparkR.init() +#' sqlCtx <- sparkRSQL.init(sc) +#' path <- "path/to/file.json" +#' df <- jsonFile(sqlCtx, path) +#' persist(df, "MEMORY_AND_DISK") +#' unpersist(df) +#'} +setMethod("unpersist", + signature(x = "DataFrame"), + function(x, blocking = TRUE) { + callJMethod(x@sdf, "unpersist", blocking) + x@env$isCached <- FALSE + x + }) + +#' Repartition +#' +#' Return a new DataFrame that has exactly numPartitions partitions. +#' +#' @param x A SparkSQL DataFrame +#' @param numPartitions The number of partitions to use. +#' @rdname repartition +#' @export +#' @examples +#'\dontrun{ +#' sc <- sparkR.init() +#' sqlCtx <- sparkRSQL.init(sc) +#' path <- "path/to/file.json" +#' df <- jsonFile(sqlCtx, path) +#' newDF <- repartition(df, 2L) +#'} +setMethod("repartition", + signature(x = "DataFrame", numPartitions = "numeric"), + function(x, numPartitions) { + sdf <- callJMethod(x@sdf, "repartition", numToInt(numPartitions)) + dataFrame(sdf) + }) + +#' toJSON +#' +#' Convert the rows of a DataFrame into JSON objects and return an RDD where +#' each element contains a JSON string. +#' +#' @param x A SparkSQL DataFrame +#' @return A StringRRDD of JSON objects +#' @rdname tojson +#' @export +#' @examples +#'\dontrun{ +#' sc <- sparkR.init() +#' sqlCtx <- sparkRSQL.init(sc) +#' path <- "path/to/file.json" +#' df <- jsonFile(sqlCtx, path) +#' newRDD <- toJSON(df) +#'} +setMethod("toJSON", + signature(x = "DataFrame"), + function(x) { + rdd <- callJMethod(x@sdf, "toJSON") + jrdd <- callJMethod(rdd, "toJavaRDD") + RDD(jrdd, serializedMode = "string") + }) + +#' saveAsParquetFile +#' +#' Save the contents of a DataFrame as a Parquet file, preserving the schema. Files written out +#' with this method can be read back in as a DataFrame using parquetFile(). +#' +#' @param x A SparkSQL DataFrame +#' @param path The directory where the file is saved +#' @rdname saveAsParquetFile +#' @export +#' @examples +#'\dontrun{ +#' sc <- sparkR.init() +#' sqlCtx <- sparkRSQL.init(sc) +#' path <- "path/to/file.json" +#' df <- jsonFile(sqlCtx, path) +#' saveAsParquetFile(df, "/tmp/sparkr-tmp/") +#'} +setMethod("saveAsParquetFile", + signature(x = "DataFrame", path = "character"), + function(x, path) { + invisible(callJMethod(x@sdf, "saveAsParquetFile", path)) + }) + +#' Distinct +#' +#' Return a new DataFrame containing the distinct rows in this DataFrame. +#' +#' @param x A SparkSQL DataFrame +#' @rdname distinct +#' @export +#' @examples +#'\dontrun{ +#' sc <- sparkR.init() +#' sqlCtx <- sparkRSQL.init(sc) +#' path <- "path/to/file.json" +#' df <- jsonFile(sqlCtx, path) +#' distinctDF <- distinct(df) +#'} +setMethod("distinct", + signature(x = "DataFrame"), + function(x) { + sdf <- callJMethod(x@sdf, "distinct") + dataFrame(sdf) + }) + +#' SampleDF +#' +#' Return a sampled subset of this DataFrame using a random seed. +#' +#' @param x A SparkSQL DataFrame +#' @param withReplacement Sampling with replacement or not +#' @param fraction The (rough) sample target fraction +#' @rdname sampleDF +#' @export +#' @examples +#'\dontrun{ +#' sc <- sparkR.init() +#' sqlCtx <- sparkRSQL.init(sc) +#' path <- "path/to/file.json" +#' df <- jsonFile(sqlCtx, path) +#' collect(sampleDF(df, FALSE, 0.5)) +#' collect(sampleDF(df, TRUE, 0.5)) +#'} +setMethod("sampleDF", + # TODO : Figure out how to send integer as java.lang.Long to JVM so + # we can send seed as an argument through callJMethod + signature(x = "DataFrame", withReplacement = "logical", + fraction = "numeric"), + function(x, withReplacement, fraction) { + if (fraction < 0.0) stop(cat("Negative fraction value:", fraction)) + sdf <- callJMethod(x@sdf, "sample", withReplacement, fraction) + dataFrame(sdf) + }) + +#' Count +#' +#' Returns the number of rows in a DataFrame +#' +#' @param x A SparkSQL DataFrame +#' +#' @rdname count +#' @export +#' @examples +#'\dontrun{ +#' sc <- sparkR.init() +#' sqlCtx <- sparkRSQL.init(sc) +#' path <- "path/to/file.json" +#' df <- jsonFile(sqlCtx, path) +#' count(df) +#' } +setMethod("count", + signature(x = "DataFrame"), + function(x) { + callJMethod(x@sdf, "count") + }) + +#' Collects all the elements of a Spark DataFrame and coerces them into an R data.frame. +#' +#' @param x A SparkSQL DataFrame +#' @param stringsAsFactors (Optional) A logical indicating whether or not string columns +#' should be converted to factors. FALSE by default. + +#' @rdname collect-methods +#' @export +#' @examples +#'\dontrun{ +#' sc <- sparkR.init() +#' sqlCtx <- sparkRSQL.init(sc) +#' path <- "path/to/file.json" +#' df <- jsonFile(sqlCtx, path) +#' collected <- collect(df) +#' firstName <- collected[[1]]$name +#' } +setMethod("collect", + signature(x = "DataFrame"), + function(x, stringsAsFactors = FALSE) { + # listCols is a list of raw vectors, one per column + listCols <- callJStatic("org.apache.spark.sql.api.r.SQLUtils", "dfToCols", x@sdf) + cols <- lapply(listCols, function(col) { + objRaw <- rawConnection(col) + numRows <- readInt(objRaw) + col <- readCol(objRaw, numRows) + close(objRaw) + col + }) + names(cols) <- columns(x) + do.call(cbind.data.frame, list(cols, stringsAsFactors = stringsAsFactors)) + }) + +#' Limit +#' +#' Limit the resulting DataFrame to the number of rows specified. +#' +#' @param x A SparkSQL DataFrame +#' @param num The number of rows to return +#' @return A new DataFrame containing the number of rows specified. +#' +#' @rdname limit +#' @export +#' @examples +#' \dontrun{ +#' sc <- sparkR.init() +#' sqlCtx <- sparkRSQL.init(sc) +#' path <- "path/to/file.json" +#' df <- jsonFile(sqlCtx, path) +#' limitedDF <- limit(df, 10) +#' } +setMethod("limit", + signature(x = "DataFrame", num = "numeric"), + function(x, num) { + res <- callJMethod(x@sdf, "limit", as.integer(num)) + dataFrame(res) + }) + +# Take the first NUM rows of a DataFrame and return a the results as a data.frame + +#' @rdname take +#' @export +#' @examples +#'\dontrun{ +#' sc <- sparkR.init() +#' sqlCtx <- sparkRSQL.init(sc) +#' path <- "path/to/file.json" +#' df <- jsonFile(sqlCtx, path) +#' take(df, 2) +#' } +setMethod("take", + signature(x = "DataFrame", num = "numeric"), + function(x, num) { + limited <- limit(x, num) + collect(limited) + }) + +#' Head +#' +#' Return the first NUM rows of a DataFrame as a data.frame. If NUM is NULL, +#' then head() returns the first 6 rows in keeping with the current data.frame +#' convention in R. +#' +#' @param x A SparkSQL DataFrame +#' @param num The number of rows to return. Default is 6. +#' @return A data.frame +#' +#' @rdname head +#' @export +#' @examples +#'\dontrun{ +#' sc <- sparkR.init() +#' sqlCtx <- sparkRSQL.init(sc) +#' path <- "path/to/file.json" +#' df <- jsonFile(sqlCtx, path) +#' head(df) +#' } +setMethod("head", + signature(x = "DataFrame"), + function(x, num = 6L) { + # Default num is 6L in keeping with R's data.frame convention + take(x, num) + }) + +#' Return the first row of a DataFrame +#' +#' @param x A SparkSQL DataFrame +#' +#' @rdname first +#' @export +#' @examples +#'\dontrun{ +#' sc <- sparkR.init() +#' sqlCtx <- sparkRSQL.init(sc) +#' path <- "path/to/file.json" +#' df <- jsonFile(sqlCtx, path) +#' first(df) +#' } +setMethod("first", + signature(x = "DataFrame"), + function(x) { + take(x, 1) + }) + +#' toRDD() +#' +#' Converts a Spark DataFrame to an RDD while preserving column names. +#' +#' @param x A Spark DataFrame +#' +#' @rdname DataFrame +#' @export +#' @examples +#'\dontrun{ +#' sc <- sparkR.init() +#' sqlCtx <- sparkRSQL.init(sc) +#' path <- "path/to/file.json" +#' df <- jsonFile(sqlCtx, path) +#' rdd <- toRDD(df) +#' } +setMethod("toRDD", + signature(x = "DataFrame"), + function(x) { + jrdd <- callJStatic("org.apache.spark.sql.api.r.SQLUtils", "dfToRowRDD", x@sdf) + colNames <- callJMethod(x@sdf, "columns") + rdd <- RDD(jrdd, serializedMode = "row") + lapply(rdd, function(row) { + names(row) <- colNames + row + }) + }) + +#' GroupBy +#' +#' Groups the DataFrame using the specified columns, so we can run aggregation on them. +#' +#' @param x a DataFrame +#' @return a GroupedData +#' @seealso GroupedData +#' @rdname DataFrame +#' @export +#' @examples +#' \dontrun{ +#' # Compute the average for all numeric columns grouped by department. +#' avg(groupBy(df, "department")) +#' +#' # Compute the max age and average salary, grouped by department and gender. +#' agg(groupBy(df, "department", "gender"), salary="avg", "age" -> "max") +#' } +setMethod("groupBy", + signature(x = "DataFrame"), + function(x, ...) { + cols <- list(...) + if (length(cols) >= 1 && class(cols[[1]]) == "character") { + sgd <- callJMethod(x@sdf, "groupBy", cols[[1]], listToSeq(cols[-1])) + } else { + jcol <- lapply(cols, function(c) { c@jc }) + sgd <- callJMethod(x@sdf, "groupBy", listToSeq(jcol)) + } + groupedData(sgd) + }) + +#' Agg +#' +#' Compute aggregates by specifying a list of columns +#' +#' @rdname DataFrame +#' @export +setMethod("agg", + signature(x = "DataFrame"), + function(x, ...) { + agg(groupBy(x), ...) + }) + + +############################## RDD Map Functions ################################## +# All of the following functions mirror the existing RDD map functions, # +# but allow for use with DataFrames by first converting to an RRDD before calling # +# the requested map function. # +################################################################################### + +#' @rdname lapply +setMethod("lapply", + signature(X = "DataFrame", FUN = "function"), + function(X, FUN) { + rdd <- toRDD(X) + lapply(rdd, FUN) + }) + +#' @rdname lapply +setMethod("map", + signature(X = "DataFrame", FUN = "function"), + function(X, FUN) { + lapply(X, FUN) + }) + +#' @rdname flatMap +setMethod("flatMap", + signature(X = "DataFrame", FUN = "function"), + function(X, FUN) { + rdd <- toRDD(X) + flatMap(rdd, FUN) + }) + +#' @rdname lapplyPartition +setMethod("lapplyPartition", + signature(X = "DataFrame", FUN = "function"), + function(X, FUN) { + rdd <- toRDD(X) + lapplyPartition(rdd, FUN) + }) + +#' @rdname lapplyPartition +setMethod("mapPartitions", + signature(X = "DataFrame", FUN = "function"), + function(X, FUN) { + lapplyPartition(X, FUN) + }) + +#' @rdname foreach +setMethod("foreach", + signature(x = "DataFrame", func = "function"), + function(x, func) { + rdd <- toRDD(x) + foreach(rdd, func) + }) + +#' @rdname foreach +setMethod("foreachPartition", + signature(x = "DataFrame", func = "function"), + function(x, func) { + rdd <- toRDD(x) + foreachPartition(rdd, func) + }) + + +############################## SELECT ################################## + +getColumn <- function(x, c) { + column(callJMethod(x@sdf, "col", c)) +} + +#' @rdname select +setMethod("$", signature(x = "DataFrame"), + function(x, name) { + getColumn(x, name) + }) + +setMethod("$<-", signature(x = "DataFrame"), + function(x, name, value) { + stopifnot(class(value) == "Column") + cols <- columns(x) + if (name %in% cols) { + cols <- lapply(cols, function(c) { + if (c == name) { + alias(value, name) + } else { + col(c) + } + }) + nx <- select(x, cols) + } else { + nx <- withColumn(x, name, value) + } + x@sdf <- nx@sdf + x + }) + +#' @rdname select +setMethod("[[", signature(x = "DataFrame"), + function(x, i) { + if (is.numeric(i)) { + cols <- columns(x) + i <- cols[[i]] + } + getColumn(x, i) + }) + +#' @rdname select +setMethod("[", signature(x = "DataFrame", i = "missing"), + function(x, i, j, ...) { + if (is.numeric(j)) { + cols <- columns(x) + j <- cols[j] + } + if (length(j) > 1) { + j <- as.list(j) + } + select(x, j) + }) + +#' Select +#' +#' Selects a set of columns with names or Column expressions. +#' @param x A DataFrame +#' @param col A list of columns or single Column or name +#' @return A new DataFrame with selected columns +#' @export +#' @rdname select +#' @examples +#' \dontrun{ +#' select(df, "*") +#' select(df, "col1", "col2") +#' select(df, df$name, df$age + 1) +#' select(df, c("col1", "col2")) +#' select(df, list(df$name, df$age + 1)) +#' # Columns can also be selected using `[[` and `[` +#' df[[2]] == df[["age"]] +#' df[,2] == df[,"age"] +#' # Similar to R data frames columns can also be selected using `$` +#' df$age +#' } +setMethod("select", signature(x = "DataFrame", col = "character"), + function(x, col, ...) { + sdf <- callJMethod(x@sdf, "select", col, toSeq(...)) + dataFrame(sdf) + }) + +#' @rdname select +#' @export +setMethod("select", signature(x = "DataFrame", col = "Column"), + function(x, col, ...) { + jcols <- lapply(list(col, ...), function(c) { + c@jc + }) + sdf <- callJMethod(x@sdf, "select", listToSeq(jcols)) + dataFrame(sdf) + }) + +#' @rdname select +#' @export +setMethod("select", + signature(x = "DataFrame", col = "list"), + function(x, col) { + cols <- lapply(col, function(c) { + if (class(c)== "Column") { + c@jc + } else { + col(c)@jc + } + }) + sdf <- callJMethod(x@sdf, "select", listToSeq(cols)) + dataFrame(sdf) + }) + +#' SelectExpr +#' +#' Select from a DataFrame using a set of SQL expressions. +#' +#' @param x A DataFrame to be selected from. +#' @param expr A string containing a SQL expression +#' @param ... Additional expressions +#' @return A DataFrame +#' @rdname selectExpr +#' @export +#' @examples +#'\dontrun{ +#' sc <- sparkR.init() +#' sqlCtx <- sparkRSQL.init(sc) +#' path <- "path/to/file.json" +#' df <- jsonFile(sqlCtx, path) +#' selectExpr(df, "col1", "(col2 * 5) as newCol") +#' } +setMethod("selectExpr", + signature(x = "DataFrame", expr = "character"), + function(x, expr, ...) { + exprList <- list(expr, ...) + sdf <- callJMethod(x@sdf, "selectExpr", listToSeq(exprList)) + dataFrame(sdf) + }) + +#' WithColumn +#' +#' Return a new DataFrame with the specified column added. +#' +#' @param x A DataFrame +#' @param colName A string containing the name of the new column. +#' @param col A Column expression. +#' @return A DataFrame with the new column added. +#' @rdname withColumn +#' @export +#' @examples +#'\dontrun{ +#' sc <- sparkR.init() +#' sqlCtx <- sparkRSQL.init(sc) +#' path <- "path/to/file.json" +#' df <- jsonFile(sqlCtx, path) +#' newDF <- withColumn(df, "newCol", df$col1 * 5) +#' } +setMethod("withColumn", + signature(x = "DataFrame", colName = "character", col = "Column"), + function(x, colName, col) { + select(x, x$"*", alias(col, colName)) + }) + +#' WithColumnRenamed +#' +#' Rename an existing column in a DataFrame. +#' +#' @param x A DataFrame +#' @param existingCol The name of the column you want to change. +#' @param newCol The new column name. +#' @return A DataFrame with the column name changed. +#' @rdname withColumnRenamed +#' @export +#' @examples +#'\dontrun{ +#' sc <- sparkR.init() +#' sqlCtx <- sparkRSQL.init(sc) +#' path <- "path/to/file.json" +#' df <- jsonFile(sqlCtx, path) +#' newDF <- withColumnRenamed(df, "col1", "newCol1") +#' } +setMethod("withColumnRenamed", + signature(x = "DataFrame", existingCol = "character", newCol = "character"), + function(x, existingCol, newCol) { + cols <- lapply(columns(x), function(c) { + if (c == existingCol) { + alias(col(c), newCol) + } else { + col(c) + } + }) + select(x, cols) + }) + +setClassUnion("characterOrColumn", c("character", "Column")) + +#' SortDF +#' +#' Sort a DataFrame by the specified column(s). +#' +#' @param x A DataFrame to be sorted. +#' @param col Either a Column object or character vector indicating the field to sort on +#' @param ... Additional sorting fields +#' @return A DataFrame where all elements are sorted. +#' @rdname sortDF +#' @export +#' @examples +#'\dontrun{ +#' sc <- sparkR.init() +#' sqlCtx <- sparkRSQL.init(sc) +#' path <- "path/to/file.json" +#' df <- jsonFile(sqlCtx, path) +#' sortDF(df, df$col1) +#' sortDF(df, "col1") +#' sortDF(df, asc(df$col1), desc(abs(df$col2))) +#' } +setMethod("sortDF", + signature(x = "DataFrame", col = "characterOrColumn"), + function(x, col, ...) { + if (class(col) == "character") { + sdf <- callJMethod(x@sdf, "sort", col, toSeq(...)) + } else if (class(col) == "Column") { + jcols <- lapply(list(col, ...), function(c) { + c@jc + }) + sdf <- callJMethod(x@sdf, "sort", listToSeq(jcols)) + } + dataFrame(sdf) + }) + +#' @rdname sortDF +#' @export +setMethod("orderBy", + signature(x = "DataFrame", col = "characterOrColumn"), + function(x, col) { + sortDF(x, col) + }) + +#' Filter +#' +#' Filter the rows of a DataFrame according to a given condition. +#' +#' @param x A DataFrame to be sorted. +#' @param condition The condition to sort on. This may either be a Column expression +#' or a string containing a SQL statement +#' @return A DataFrame containing only the rows that meet the condition. +#' @rdname filter +#' @export +#' @examples +#'\dontrun{ +#' sc <- sparkR.init() +#' sqlCtx <- sparkRSQL.init(sc) +#' path <- "path/to/file.json" +#' df <- jsonFile(sqlCtx, path) +#' filter(df, "col1 > 0") +#' filter(df, df$col2 != "abcdefg") +#' } +setMethod("filter", + signature(x = "DataFrame", condition = "characterOrColumn"), + function(x, condition) { + if (class(condition) == "Column") { + condition <- condition@jc + } + sdf <- callJMethod(x@sdf, "filter", condition) + dataFrame(sdf) + }) + +#' @rdname filter +#' @export +setMethod("where", + signature(x = "DataFrame", condition = "characterOrColumn"), + function(x, condition) { + filter(x, condition) + }) + +#' Join +#' +#' Join two DataFrames based on the given join expression. +#' +#' @param x A Spark DataFrame +#' @param y A Spark DataFrame +#' @param joinExpr (Optional) The expression used to perform the join. joinExpr must be a +#' Column expression. If joinExpr is omitted, join() wil perform a Cartesian join +#' @param joinType The type of join to perform. The following join types are available: +#' 'inner', 'outer', 'left_outer', 'right_outer', 'semijoin'. The default joinType is "inner". +#' @return A DataFrame containing the result of the join operation. +#' @rdname join +#' @export +#' @examples +#'\dontrun{ +#' sc <- sparkR.init() +#' sqlCtx <- sparkRSQL.init(sc) +#' df1 <- jsonFile(sqlCtx, path) +#' df2 <- jsonFile(sqlCtx, path2) +#' join(df1, df2) # Performs a Cartesian +#' join(df1, df2, df1$col1 == df2$col2) # Performs an inner join based on expression +#' join(df1, df2, df1$col1 == df2$col2, "right_outer") +#' } +setMethod("join", + signature(x = "DataFrame", y = "DataFrame"), + function(x, y, joinExpr = NULL, joinType = NULL) { + if (is.null(joinExpr)) { + sdf <- callJMethod(x@sdf, "join", y@sdf) + } else { + if (class(joinExpr) != "Column") stop("joinExpr must be a Column") + if (is.null(joinType)) { + sdf <- callJMethod(x@sdf, "join", y@sdf, joinExpr@jc) + } else { + if (joinType %in% c("inner", "outer", "left_outer", "right_outer", "semijoin")) { + sdf <- callJMethod(x@sdf, "join", y@sdf, joinExpr@jc, joinType) + } else { + stop("joinType must be one of the following types: ", + "'inner', 'outer', 'left_outer', 'right_outer', 'semijoin'") + } + } + } + dataFrame(sdf) + }) + +#' UnionAll +#' +#' Return a new DataFrame containing the union of rows in this DataFrame +#' and another DataFrame. This is equivalent to `UNION ALL` in SQL. +#' +#' @param x A Spark DataFrame +#' @param y A Spark DataFrame +#' @return A DataFrame containing the result of the union. +#' @rdname unionAll +#' @export +#' @examples +#'\dontrun{ +#' sc <- sparkR.init() +#' sqlCtx <- sparkRSQL.init(sc) +#' df1 <- jsonFile(sqlCtx, path) +#' df2 <- jsonFile(sqlCtx, path2) +#' unioned <- unionAll(df, df2) +#' } +setMethod("unionAll", + signature(x = "DataFrame", y = "DataFrame"), + function(x, y) { + unioned <- callJMethod(x@sdf, "unionAll", y@sdf) + dataFrame(unioned) + }) + +#' Intersect +#' +#' Return a new DataFrame containing rows only in both this DataFrame +#' and another DataFrame. This is equivalent to `INTERSECT` in SQL. +#' +#' @param x A Spark DataFrame +#' @param y A Spark DataFrame +#' @return A DataFrame containing the result of the intersect. +#' @rdname intersect +#' @export +#' @examples +#'\dontrun{ +#' sc <- sparkR.init() +#' sqlCtx <- sparkRSQL.init(sc) +#' df1 <- jsonFile(sqlCtx, path) +#' df2 <- jsonFile(sqlCtx, path2) +#' intersectDF <- intersect(df, df2) +#' } +setMethod("intersect", + signature(x = "DataFrame", y = "DataFrame"), + function(x, y) { + intersected <- callJMethod(x@sdf, "intersect", y@sdf) + dataFrame(intersected) + }) + +#' Subtract +#' +#' 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 +#' @export +#' @examples +#'\dontrun{ +#' sc <- sparkR.init() +#' sqlCtx <- sparkRSQL.init(sc) +#' df1 <- jsonFile(sqlCtx, path) +#' df2 <- jsonFile(sqlCtx, path2) +#' subtractDF <- subtract(df, df2) +#' } +setMethod("subtract", + signature(x = "DataFrame", y = "DataFrame"), + function(x, y) { + subtracted <- callJMethod(x@sdf, "except", y@sdf) + dataFrame(subtracted) + }) + +#' Save the contents of the DataFrame to a data source +#' +#' The data source is specified by the `source` and a set of options (...). +#' If `source` is not specified, the default data source configured by +#' spark.sql.sources.default will be used. +#' +#' Additionally, mode is used to specify the behavior of the save operation when +#' data already exists in the data source. There are four modes: +#' append: Contents of this DataFrame are expected to be appended to existing data. +#' overwrite: Existing data is expected to be overwritten by the contents of +# this DataFrame. +#' error: An exception is expected to be thrown. +#' ignore: The save operation is expected to not save the contents of the DataFrame +# and to not change the existing data. +#' +#' @param df A SparkSQL DataFrame +#' @param path A name for the table +#' @param source A name for external data source +#' @param mode One of 'append', 'overwrite', 'error', 'ignore' +#' +#' @rdname saveAsTable +#' @export +#' @examples +#'\dontrun{ +#' sc <- sparkR.init() +#' sqlCtx <- sparkRSQL.init(sc) +#' path <- "path/to/file.json" +#' df <- jsonFile(sqlCtx, path) +#' saveAsTable(df, "myfile") +#' } +setMethod("saveDF", + signature(df = "DataFrame", path = 'character', source = 'character', + mode = 'character'), + function(df, path = NULL, source = NULL, mode = "append", ...){ + if (is.null(source)) { + sqlCtx <- get(".sparkRSQLsc", envir = .sparkREnv) + source <- callJMethod(sqlCtx, "getConf", "spark.sql.sources.default", + "org.apache.spark.sql.parquet") + } + allModes <- c("append", "overwrite", "error", "ignore") + if (!(mode %in% allModes)) { + stop('mode should be one of "append", "overwrite", "error", "ignore"') + } + jmode <- callJStatic("org.apache.spark.sql.api.r.SQLUtils", "saveMode", mode) + options <- varargsToEnv(...) + if (!is.null(path)) { + options[['path']] = path + } + callJMethod(df@sdf, "save", source, jmode, options) + }) + + +#' saveAsTable +#' +#' Save the contents of the DataFrame to a data source as a table +#' +#' The data source is specified by the `source` and a set of options (...). +#' If `source` is not specified, the default data source configured by +#' spark.sql.sources.default will be used. +#' +#' Additionally, mode is used to specify the behavior of the save operation when +#' data already exists in the data source. There are four modes: +#' append: Contents of this DataFrame are expected to be appended to existing data. +#' overwrite: Existing data is expected to be overwritten by the contents of +# this DataFrame. +#' error: An exception is expected to be thrown. +#' ignore: The save operation is expected to not save the contents of the DataFrame +# and to not change the existing data. +#' +#' @param df A SparkSQL DataFrame +#' @param tableName A name for the table +#' @param source A name for external data source +#' @param mode One of 'append', 'overwrite', 'error', 'ignore' +#' +#' @rdname saveAsTable +#' @export +#' @examples +#'\dontrun{ +#' sc <- sparkR.init() +#' sqlCtx <- sparkRSQL.init(sc) +#' path <- "path/to/file.json" +#' df <- jsonFile(sqlCtx, path) +#' saveAsTable(df, "myfile") +#' } +setMethod("saveAsTable", + signature(df = "DataFrame", tableName = 'character', source = 'character', + mode = 'character'), + function(df, tableName, source = NULL, mode="append", ...){ + if (is.null(source)) { + sqlCtx <- get(".sparkRSQLsc", envir = .sparkREnv) + source <- callJMethod(sqlCtx, "getConf", "spark.sql.sources.default", + "org.apache.spark.sql.parquet") + } + allModes <- c("append", "overwrite", "error", "ignore") + if (!(mode %in% allModes)) { + stop('mode should be one of "append", "overwrite", "error", "ignore"') + } + jmode <- callJStatic("org.apache.spark.sql.api.r.SQLUtils", "saveMode", mode) + options <- varargsToEnv(...) + callJMethod(df@sdf, "saveAsTable", tableName, source, jmode, options) + }) + --------------------------------------------------------------------- To unsubscribe, e-mail: commits-unsubscr...@spark.apache.org For additional commands, e-mail: commits-h...@spark.apache.org