Returns a stratified sample without replacement

Returns a stratified sample without replacement based on the fraction given on each stratum.

Usage

sampleBy(x, col, fractions, seed)

# S4 method for SparkDataFrame,character,list,numeric
sampleBy(x, col, fractions, seed)

Arguments

x

A SparkDataFrame

col

column that defines strata

fractions

A named list giving sampling fraction for each stratum. If a stratum is not specified, we treat its fraction as zero.

seed

random seed

Value

A new SparkDataFrame that represents the stratified sample

Note

sampleBy since 1.6.0

See also

Other stat functions: approxQuantile(), corr(), cov(), crosstab(), freqItems()

Examples

if (FALSE) {
df <- read.json("/path/to/file.json")
sample <- sampleBy(df, "key", fractions, 36)
}