hof_transform

Transform Array Column

Description

Apply an element-wise transformation function to an array column (this is essentially a dplyr wrapper for the transform(array<T>, function<T, U>): array<U> and the transform(array<T>, function<T, Int, U>): array<U> built-in Spark SQL functions)

Usage

hof_transform(x, func, expr = NULL, dest_col = NULL, ...)

Arguments

Argument Description
x The Spark data frame to transform
func The transformation to apply
expr The array being transformed, could be any SQL expression evaluating to an array (default: the last column of the Spark data frame)
dest_col Column to store the transformed result (default: expr)
Additional params to dplyr::mutate

Examples



library(sparklyr)
sc <- spark_connect(master = "local")
# applies the (x -> x * x) transformation to elements of all arrays
copy_to(sc, tibble::tibble(arr = list(1:5, 21:25))) %>%
  hof_transform(~ .x * .x)