"rbind" recombination - Combine ddf divisions by row binding
combRbind(...)additional attributes to define the combiner (currently only used internally)
combRbind is passed to the argument combine in recombine
divide, recombine, combDdo, combDdf, combCollect, combMeanCoef, combMean
# NOT RUN {
# Create a distributed data frame using the iris data set
bySpecies <- divide(iris, by = "Species")
# Create a function that will calculate the standard deviation of each
# variable in in a subset. The calls to 'as.data.frame()' and 't()'
# convert the vector output of 'apply()' into a data.frame with a single row
sdCol <- function(x) as.data.frame(t(apply(x, 2, sd)))
# Combine the results using rbind
combined <- recombine(addTransform(bySpecies, sdCol), combine = combRbind)
class(combined)
combined
# A more concise (and readable) way to do it
bySpecies %>%
addTransform(sdCol) %>%
recombine(combRbind)
# }
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