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Last data update: 2014.03.03

R: Reads a cdb file

read.cdb

R Documentation

Reads a cdb file

Description

This function reads a cdb file (or its text version) and creates a data frame with the keys and values.

Usage

read.cdb(file, type=c("cdb","txt"))

Arguments

`file`	The name of the cdb file to read.
`type`	A character string describing the type of file. Value `cdb` reads a file with the native format; `txt` needs a text record format. See the Details section.

Details

This function reads data files in the cdb format or in its text version. The format is described in the documents of the reference section.

It reads all the keys and values and transforms them as a data frame with two columns.

Value

An object of the class data.frame with two columns: The first one collects the keys and the second one shows the values.

Author(s)

Emilio Torres Manzanera

References

D. J. Bernstein The cdbmake and cdbdump programs http://cr.yp.to/cdb/cdbmake.html

Yusuke Shinyama (2003) Constant Database (cdb) Internals http://www.unixuser.org/~euske/doc/cdbinternals/

Michael Tokarev (2012) TinyCDB - a Constant DataBase http://www.corpit.ru/mjt/tinycdb.html

Examples

packages <- rownames(as.data.frame(installed.packages()))
set.seed(123)
a <- data.frame(key=sample(packages, 10, replace = TRUE),
                value=sample(packages, 10, replace = TRUE))
write.cdb(a, "Base.txt", type="txt")

b <- read.cdb("Base.txt", type="txt")
b

c <- read.cdb(system.file("extdata", "example.cdb",
                        package = "cdb"))
c