Subsample a data frame object

A simple function that subsamples a data frame or numeric vector in order to "thin" large datasets.

subsample(x, n = NULL, length.out = NULL, random_start = FALSE, plot = TRUE)

Arguments

x

data frame or vector. The data to subsample.

n

numeric. Subsample every n elements or rows.

length.out

numeric. Subsample to a specific length or number of rows.

random_start

logical. Defaults to FALSE. If TRUE, randomises the start position from which to start the subsample (applies to n input only).

plot

logical. Defaults to TRUE. Plots the data. If there are multiple columns in the data frame, only the first two are plotted. Vectors are plotted against a position index.

Value

Returns a subsampled data frame or vector object depending on input.

Details

Two subsampling methods are provided. The n input selects every n'th element or row, or alternatively the length.out input uniformly subsamples the data to the desired length.

More

For additional help, documentation, vignettes, and more visit the respR website at https://januarharianto.github.io/respR/

Examples

# Subsample by every 200th row:
subsample(squid.rd, n = 200)


# Subsample to 100 rows:
subsample(sardine.rd, length.out = 100)
#> subsample: plotting first column of data only.


# Subsample with random starting position:
subsample(sardine.rd, n = 20, random_start = TRUE)
#> subsample: plotting first column of data only.


# Subsample a vector
subsample(sardine.rd[[2]], n = 20)