R: Write Transactions or Associations to a File

write {arules} | R Documentation

## Write Transactions or Associations to a File

### Description

Provides the generic function `write` and the S4 methods to write transactions or associations (itemsets, rules) to a file.

### Usage

    write(x, file = "",...)
    ## S4 method for signature 'transactions'
    write(x, file="", format = c("basket", "single"),
                    sep=" ", quote=TRUE, ...)
    ## S4 method for signature 'associations'
    write(x, file="", sep=" ", quote=TRUE, ...)

### Arguments

`x` | the transactions or associations (rules, itemsets, etc.) object.
`file` | either a character string naming a file or a connection open for writing. '""' indicates output to the console.
`format` | format to write transactions.
`sep` | the field separator string. Values within each row of x are separated by this string. Use `quote=TRUE` and `sep=","` for saving data as in csv format.
`quote` | a logical value. Quote fields?
`...` | further arguments passed on to `write.table` or `write`. Use `fileEncoding` to set the encoding used for writing the file.

### Details

For associations (rules and itemsets) `write` first uses coercion to data.frame to obtain a printable form of `x` and then uses `write.table` to write the data to disk.

Transactions can be saved in basket (one line per transaction) or in single (one line per item) format.

Note: To save and load associations in compact form, use `save` and `load` from the base package. Alternatively, association can be written to disk in PMML (Predictive Model Markup Language) via `write.PMML`. This requiresvpackages pmml.

### Author(s)

Michael Hahsler

### See Also

`read.transactions` for reading transactions from a file, `read.PMML` and `write.PMML` for reading/writing associations in PMML format, `write.table` (in base), `transactions-class`, `associations-class`

### Examples

    data("Epub")

    ## write the formated transactions to screen (basket format)
    write(head(Epub))

    ## write the formated transactions to screen (single format)
    write(head(Epub), format="single")

    ## write the formated result to file in CSV format
    write(Epub, file = "data.csv", format="single", sep = ",")

    ## write rules in CSV format
    rules <- apriori(Epub, parameter=list(support=0.0005, conf=0.8))
    write(rules, file = "data.csv", sep = ",")

    unlink("data.csv") # tidy up

[Package arules version 1.6-7 Index]