Sample a dataframe for n obs and returns full dataframe if n > nrow

Source: R/sample.R

Sample a dataframe for n obs and returns full dataframe if n > nrow

sample_all_or_n(data, n, replace = FALSE, weight = NULL)

Arguments

data

A dataframe or tibble.
n

Number of rows to sample. If n is greater than the row count, the dataframe will be returned unchanged.
replace

Sample with or without replacement?
weight

Sampling weights. This must evaluate to a vector of non-negative numbers the same length as the input. Weights are automatically standardised to sum to 1.

See also

sample_n

Examples

library(tidyverse)
test_data <- 
        tibble(
                Group = sample(c("Apple", "Pear"), size = 10, replace = TRUE),
                A     = sample(c(NA_integer_, 1:3), size = 10, replace = TRUE),
                B     = sample(c(NA_integer_, 4:6), size = 10, replace = TRUE)
        )


# Sample less than row count
sample_all_or_n(data = test_data,
                n = 5)

#> # A tibble: 5 x 3
#>   Group     A     B
#>   <chr> <int> <int>
#> 1 Apple     1     5
#> 2 Apple     3     4
#> 3 Pear      3     4
#> 4 Apple     3    NA
#> 5 Pear      1     6

# When n is greater than row count, the dataframe is returned unchanged
sample_all_or_n(data = test_data,
                n = 11)

#> # A tibble: 10 x 3
#>    Group     A     B
#>    <chr> <int> <int>
#>  1 Pear      1     6
#>  2 Apple     1     5
#>  3 Apple     3    NA
#>  4 Apple     3     4
#>  5 Pear      3     4
#>  6 Apple    NA     4
#>  7 Apple    NA     4
#>  8 Pear     NA    NA
#>  9 Apple    NA     6
#> 10 Apple     2     5