From 2a4e00ca4d4e7a148b4ff8ce0ad1c6d517cee55f Mon Sep 17 00:00:00 2001 From: felixcheung Date: Fri, 28 Aug 2015 18:35:01 -0700 Subject: [SPARK-9803] [SPARKR] Add subset and transform + tests Add subset and transform Also reorganize `[` & `[[` to subset instead of select Note: for transform, transform is very similar to mutate. Spark doesn't seem to replace existing column with the name in mutate (ie. `mutate(df, age = df$age + 2)` - returned DataFrame has 2 columns with the same name 'age'), so therefore not doing that for now in transform. Though it is clearly stated it should replace column with matching name (should I open a JIRA for mutate/transform?) Author: felixcheung Closes #8503 from felixcheung/rsubset_transform. --- R/pkg/NAMESPACE | 2 ++ R/pkg/R/DataFrame.R | 70 +++++++++++++++++++++++++++++++--------- R/pkg/R/generics.R | 10 +++++- R/pkg/inst/tests/test_sparkSQL.R | 20 +++++++++++- 4 files changed, 85 insertions(+), 17 deletions(-) (limited to 'R') diff --git a/R/pkg/NAMESPACE b/R/pkg/NAMESPACE index 5286c01986..9d39630706 100644 --- a/R/pkg/NAMESPACE +++ b/R/pkg/NAMESPACE @@ -69,9 +69,11 @@ exportMethods("arrange", "selectExpr", "show", "showDF", + "subset", "summarize", "summary", "take", + "transform", "unionAll", "unique", "unpersist", diff --git a/R/pkg/R/DataFrame.R b/R/pkg/R/DataFrame.R index 74de7c81e3..8a00238b41 100644 --- a/R/pkg/R/DataFrame.R +++ b/R/pkg/R/DataFrame.R @@ -987,7 +987,7 @@ setMethod("$<-", signature(x = "DataFrame"), setClassUnion("numericOrcharacter", c("numeric", "character")) -#' @rdname select +#' @rdname subset #' @name [[ setMethod("[[", signature(x = "DataFrame", i = "numericOrcharacter"), function(x, i) { @@ -998,7 +998,7 @@ setMethod("[[", signature(x = "DataFrame", i = "numericOrcharacter"), getColumn(x, i) }) -#' @rdname select +#' @rdname subset #' @name [ setMethod("[", signature(x = "DataFrame", i = "missing"), function(x, i, j, ...) { @@ -1012,7 +1012,7 @@ setMethod("[", signature(x = "DataFrame", i = "missing"), select(x, j) }) -#' @rdname select +#' @rdname subset #' @name [ setMethod("[", signature(x = "DataFrame", i = "Column"), function(x, i, j, ...) { @@ -1020,12 +1020,43 @@ setMethod("[", signature(x = "DataFrame", i = "Column"), # https://stat.ethz.ch/R-manual/R-devel/library/base/html/Extract.data.frame.html filtered <- filter(x, i) if (!missing(j)) { - filtered[, j] + filtered[, j, ...] } else { filtered } }) +#' Subset +#' +#' Return subsets of DataFrame according to given conditions +#' @param x A DataFrame +#' @param subset A logical expression to filter on rows +#' @param select expression for the single Column or a list of columns to select from the DataFrame +#' @return A new DataFrame containing only the rows that meet the condition with selected columns +#' @export +#' @rdname subset +#' @name subset +#' @aliases [ +#' @family subsetting functions +#' @examples +#' \dontrun{ +#' # Columns can be selected using `[[` and `[` +#' df[[2]] == df[["age"]] +#' df[,2] == df[,"age"] +#' df[,c("name", "age")] +#' # Or to filter rows +#' df[df$age > 20,] +#' # DataFrame can be subset on both rows and Columns +#' df[df$name == "Smith", c(1,2)] +#' df[df$age %in% c(19, 30), 1:2] +#' subset(df, df$age %in% c(19, 30), 1:2) +#' subset(df, df$age %in% c(19), select = c(1,2)) +#' } +setMethod("subset", signature(x = "DataFrame"), + function(x, subset, select, ...) { + x[subset, select, ...] + }) + #' Select #' #' Selects a set of columns with names or Column expressions. @@ -1034,6 +1065,8 @@ setMethod("[", signature(x = "DataFrame", i = "Column"), #' @return A new DataFrame with selected columns #' @export #' @rdname select +#' @name select +#' @family subsetting functions #' @examples #' \dontrun{ #' select(df, "*") @@ -1041,15 +1074,8 @@ setMethod("[", signature(x = "DataFrame", i = "Column"), #' select(df, df$name, df$age + 1) #' select(df, c("col1", "col2")) #' select(df, list(df$name, df$age + 1)) -#' # Columns can also be selected using `[[` and `[` -#' df[[2]] == df[["age"]] -#' df[,2] == df[,"age"] -#' df[,c("name", "age")] #' # Similar to R data frames columns can also be selected using `$` #' df$age -#' # It can also be subset on rows and Columns -#' df[df$name == "Smith", c(1,2)] -#' df[df$age %in% c(19, 30), 1:2] #' } setMethod("select", signature(x = "DataFrame", col = "character"), function(x, col, ...) { @@ -1121,7 +1147,7 @@ setMethod("selectExpr", #' @return A DataFrame with the new column added. #' @rdname withColumn #' @name withColumn -#' @aliases mutate +#' @aliases mutate transform #' @export #' @examples #'\dontrun{ @@ -1141,11 +1167,12 @@ setMethod("withColumn", #' #' Return a new DataFrame with the specified columns added. #' -#' @param x A DataFrame +#' @param .data A DataFrame #' @param col a named argument of the form name = col #' @return A new DataFrame with the new columns added. #' @rdname withColumn #' @name mutate +#' @aliases withColumn transform #' @export #' @examples #'\dontrun{ @@ -1155,10 +1182,12 @@ setMethod("withColumn", #' df <- jsonFile(sqlContext, path) #' newDF <- mutate(df, newCol = df$col1 * 5, newCol2 = df$col1 * 2) #' names(newDF) # Will contain newCol, newCol2 +#' newDF2 <- transform(df, newCol = df$col1 / 5, newCol2 = df$col1 * 2) #' } setMethod("mutate", - signature(x = "DataFrame"), - function(x, ...) { + signature(.data = "DataFrame"), + function(.data, ...) { + x <- .data cols <- list(...) stopifnot(length(cols) > 0) stopifnot(class(cols[[1]]) == "Column") @@ -1173,6 +1202,16 @@ setMethod("mutate", do.call(select, c(x, x$"*", cols)) }) +#' @export +#' @rdname withColumn +#' @name transform +#' @aliases withColumn mutate +setMethod("transform", + signature(`_data` = "DataFrame"), + function(`_data`, ...) { + mutate(`_data`, ...) + }) + #' WithColumnRenamed #' #' Rename an existing column in a DataFrame. @@ -1300,6 +1339,7 @@ setMethod("orderBy", #' @return A DataFrame containing only the rows that meet the condition. #' @rdname filter #' @name filter +#' @family subsetting functions #' @export #' @examples #'\dontrun{ diff --git a/R/pkg/R/generics.R b/R/pkg/R/generics.R index b578b8789d..43dd8d283a 100644 --- a/R/pkg/R/generics.R +++ b/R/pkg/R/generics.R @@ -467,7 +467,7 @@ setGeneric("merge") #' @rdname withColumn #' @export -setGeneric("mutate", function(x, ...) {standardGeneric("mutate") }) +setGeneric("mutate", function(.data, ...) {standardGeneric("mutate") }) #' @rdname arrange #' @export @@ -507,6 +507,10 @@ setGeneric("saveAsTable", function(df, tableName, source, mode, ...) { standardGeneric("saveAsTable") }) +#' @rdname withColumn +#' @export +setGeneric("transform", function(`_data`, ...) {standardGeneric("transform") }) + #' @rdname write.df #' @export setGeneric("write.df", function(df, path, ...) { standardGeneric("write.df") }) @@ -531,6 +535,10 @@ setGeneric("selectExpr", function(x, expr, ...) { standardGeneric("selectExpr") #' @export setGeneric("showDF", function(x,...) { standardGeneric("showDF") }) +# @rdname subset +# @export +setGeneric("subset", function(x, subset, select, ...) { standardGeneric("subset") }) + #' @rdname agg #' @export setGeneric("summarize", function(x,...) { standardGeneric("summarize") }) diff --git a/R/pkg/inst/tests/test_sparkSQL.R b/R/pkg/inst/tests/test_sparkSQL.R index 933b11c8ee..0da5e38654 100644 --- a/R/pkg/inst/tests/test_sparkSQL.R +++ b/R/pkg/inst/tests/test_sparkSQL.R @@ -612,6 +612,10 @@ test_that("subsetting", { df5 <- df[df$age %in% c(19), c(1,2)] expect_equal(count(df5), 1) expect_equal(columns(df5), c("name", "age")) + + df6 <- subset(df, df$age %in% c(30), c(1,2)) + expect_equal(count(df6), 1) + expect_equal(columns(df6), c("name", "age")) }) test_that("selectExpr() on a DataFrame", { @@ -1028,7 +1032,7 @@ test_that("withColumn() and withColumnRenamed()", { expect_equal(columns(newDF2)[1], "newerAge") }) -test_that("mutate(), rename() and names()", { +test_that("mutate(), transform(), rename() and names()", { df <- jsonFile(sqlContext, jsonPath) newDF <- mutate(df, newAge = df$age + 2) expect_equal(length(columns(newDF)), 3) @@ -1042,6 +1046,20 @@ test_that("mutate(), rename() and names()", { names(newDF2) <- c("newerName", "evenNewerAge") expect_equal(length(names(newDF2)), 2) expect_equal(names(newDF2)[1], "newerName") + + transformedDF <- transform(df, newAge = -df$age, newAge2 = df$age / 2) + expect_equal(length(columns(transformedDF)), 4) + expect_equal(columns(transformedDF)[3], "newAge") + expect_equal(columns(transformedDF)[4], "newAge2") + expect_equal(first(filter(transformedDF, transformedDF$name == "Andy"))$newAge, -30) + + # test if transform on local data frames works + # ensure the proper signature is used - otherwise this will fail to run + attach(airquality) + result <- transform(Ozone, logOzone = log(Ozone)) + expect_equal(nrow(result), 153) + expect_equal(ncol(result), 2) + detach(airquality) }) test_that("write.df() on DataFrame and works with parquetFile", { -- cgit v1.2.3