R: "Compress" a data frame.

compress.data.frame {statnet.common} | R Documentation

## "Compress" a data frame.

### Description

`compress.data.frame` "compresses" a data frame, returning unique rows and a tally of the number of times each row is repeated, as well as a permutation vector that can reconstruct the original data frame. `decompress.data.frame` reconstructs the original data frame.

### Usage

    compress.data.frame(x)

    decompress.data.frame(x)

### Arguments

`x` | For `compress.data.frame` a `data.frame` to be compressed. For `decompress.data.frame` a `list` as returned by `compress.data.frame`.

### Value

For `compress.data.frame`, a `list` with three elements:

`rows` | Unique rows of `x`
`frequencies` | A vector of the same length as the number or rows, giving the number of times the corresponding row is repeated
`ordering` | A vector such that if `c` is the compressed data frame, `c$rows[c$ordering,,drop=FALSE]` equals the original data frame, except for row names
`rownames` | Row names of `x`

For `decompress.data.frame`, the original data frame.

### See Also

`data.frame`

### Examples

    (x <- data.frame(V1=sample.int(3,30,replace=TRUE),
                     V2=sample.int(2,30,replace=TRUE),
                     V3=sample.int(4,30,replace=TRUE)))

    (c <- compress.data.frame(x))

    stopifnot(all(decompress.data.frame(c)==x))

[Package statnet.common version 4.2.0 Index]