Repository: spark Updated Branches: refs/heads/master 500436b43 -> 1f73d3589
[SPARK-20550][SPARKR] R wrapper for Dataset.alias ## What changes were proposed in this pull request? - Add SparkR wrapper for `Dataset.alias`. - Adjust roxygen annotations for `functions.alias` (including example usage). ## How was this patch tested? Unit tests, `check_cran.sh`. Author: zero323 <zero...@users.noreply.github.com> Closes #17825 from zero323/SPARK-20550. Project: http://git-wip-us.apache.org/repos/asf/spark/repo Commit: http://git-wip-us.apache.org/repos/asf/spark/commit/1f73d358 Tree: http://git-wip-us.apache.org/repos/asf/spark/tree/1f73d358 Diff: http://git-wip-us.apache.org/repos/asf/spark/diff/1f73d358 Branch: refs/heads/master Commit: 1f73d3589a84b78473598c17ac328a9805896778 Parents: 500436b Author: zero323 <zero...@users.noreply.github.com> Authored: Sun May 7 16:24:42 2017 -0700 Committer: Felix Cheung <felixche...@apache.org> Committed: Sun May 7 16:24:42 2017 -0700 ---------------------------------------------------------------------- R/pkg/R/DataFrame.R | 24 ++++++++++++++++++++++++ R/pkg/R/column.R | 16 ++++++++-------- R/pkg/R/generics.R | 11 +++++++++++ R/pkg/inst/tests/testthat/test_sparkSQL.R | 10 ++++++++++ 4 files changed, 53 insertions(+), 8 deletions(-) ---------------------------------------------------------------------- http://git-wip-us.apache.org/repos/asf/spark/blob/1f73d358/R/pkg/R/DataFrame.R ---------------------------------------------------------------------- diff --git a/R/pkg/R/DataFrame.R b/R/pkg/R/DataFrame.R index 1c88692..b56dddc 100644 --- a/R/pkg/R/DataFrame.R +++ b/R/pkg/R/DataFrame.R @@ -3745,3 +3745,27 @@ setMethod("hint", jdf <- callJMethod(x@sdf, "hint", name, parameters) dataFrame(jdf) }) + +#' alias +#' +#' @aliases alias,SparkDataFrame-method +#' @family SparkDataFrame functions +#' @rdname alias +#' @name alias +#' @export +#' @examples +#' \dontrun{ +#' df <- alias(createDataFrame(mtcars), "mtcars") +#' avg_mpg <- alias(agg(groupBy(df, df$cyl), avg(df$mpg)), "avg_mpg") +#' +#' head(select(df, column("mtcars.mpg"))) +#' head(join(df, avg_mpg, column("mtcars.cyl") == column("avg_mpg.cyl"))) +#' } +#' @note alias(SparkDataFrame) since 2.3.0 +setMethod("alias", + signature(object = "SparkDataFrame"), + function(object, data) { + stopifnot(is.character(data)) + sdf <- callJMethod(object@sdf, "alias", data) + dataFrame(sdf) + }) http://git-wip-us.apache.org/repos/asf/spark/blob/1f73d358/R/pkg/R/column.R ---------------------------------------------------------------------- diff --git a/R/pkg/R/column.R b/R/pkg/R/column.R index 147ee4b..5740780 100644 --- a/R/pkg/R/column.R +++ b/R/pkg/R/column.R @@ -130,19 +130,19 @@ createMethods <- function() { createMethods() -#' alias -#' -#' Set a new name for a column -#' -#' @param object Column to rename -#' @param data new name to use -#' #' @rdname alias #' @name alias #' @aliases alias,Column-method #' @family colum_func #' @export -#' @note alias since 1.4.0 +#' @examples \dontrun{ +#' df <- createDataFrame(iris) +#' +#' head(select( +#' df, alias(df$Sepal_Length, "slength"), alias(df$Petal_Length, "plength") +#' )) +#' } +#' @note alias(Column) since 1.4.0 setMethod("alias", signature(object = "Column"), function(object, data) { http://git-wip-us.apache.org/repos/asf/spark/blob/1f73d358/R/pkg/R/generics.R ---------------------------------------------------------------------- diff --git a/R/pkg/R/generics.R b/R/pkg/R/generics.R index e835ef3..3c84bf8 100644 --- a/R/pkg/R/generics.R +++ b/R/pkg/R/generics.R @@ -387,6 +387,17 @@ setGeneric("value", function(bcast) { standardGeneric("value") }) #' @export setGeneric("agg", function (x, ...) { standardGeneric("agg") }) +#' alias +#' +#' Returns a new SparkDataFrame or a Column with an alias set. Equivalent to SQL "AS" keyword. +#' +#' @name alias +#' @rdname alias +#' @param object x a SparkDataFrame or a Column +#' @param data new name to use +#' @return a SparkDataFrame or a Column +NULL + #' @rdname arrange #' @export setGeneric("arrange", function(x, col, ...) { standardGeneric("arrange") }) http://git-wip-us.apache.org/repos/asf/spark/blob/1f73d358/R/pkg/inst/tests/testthat/test_sparkSQL.R ---------------------------------------------------------------------- diff --git a/R/pkg/inst/tests/testthat/test_sparkSQL.R b/R/pkg/inst/tests/testthat/test_sparkSQL.R index 232246d..0856bab 100644 --- a/R/pkg/inst/tests/testthat/test_sparkSQL.R +++ b/R/pkg/inst/tests/testthat/test_sparkSQL.R @@ -1223,6 +1223,16 @@ test_that("select with column", { expect_equal(columns(df4), c("name", "age")) expect_equal(count(df4), 3) + # Test select with alias + df5 <- alias(df, "table") + + expect_equal(columns(select(df5, column("table.name"))), "name") + expect_equal(columns(select(df5, "table.name")), "name") + + # Test that stats::alias is not masked + expect_is(alias(aov(yield ~ block + N * P * K, npk)), "listof") + + expect_error(select(df, c("name", "age"), "name"), "To select multiple columns, use a character vector or list for col") }) --------------------------------------------------------------------- To unsubscribe, e-mail: commits-unsubscr...@spark.apache.org For additional commands, e-mail: commits-h...@spark.apache.org
