duplicated2: Determine Duplicate Elements

In gdata: Various R Programming Tools for Data Manipulation

Description

duplicated2() determines which elements of a vector or data frame are duplicates, and returns a logical vector indicating which elements (rows) are duplicates.

Usage

duplicated2(x, bothWays=TRUE, ...)

Arguments

x	a vector or a data frame or an array or NULL.
bothWays	if TRUE (the default), duplication should be considered from both sides. For more information see the argument fromLast to the function duplicated.
...	further arguments passed down to duplicated() and its methods.

Details

The standard duplicated function (in package:base) only returns TRUE for the second and following copies of each duplicated value (second-to-last and earlier when fromLast=TRUE). This function returns all duplicated elementes, including the first (last) value.

When bothWays is FALSE, duplicated2() defaults to a duplicated call. When bothWays is TRUE, the following call is being executed: duplicated(x, ...) | duplicated(x, fromLast=TRUE, ...)

Value

For a vector input, a logical vector of the same length as x. For a data frame, a logical vector with one element for each row. For a matrix or array, and when MARGIN = 0, a logical array with the same dimensions and dimnames.

For more details see duplicated.

Author(s)

Liviu Andronic

See Also

duplicated, unique

Examples

  data(iris)
  iris[duplicated(iris), ]                 # 2nd duplicated value
  iris[duplicated(iris, fromLast=TRUE), ]  # 1st duplicated value
  iris[duplicated2(iris), ]                # both duplicated values

Example output

sh: 1: /usr/bin/perl: Permission denied
gdata: Unable to load perl libaries needed by read.xls()
gdata: to support 'XLX' (Excel 97-2004) files.

gdata: Unable to load perl libaries needed by read.xls()
gdata: to support 'XLSX' (Excel 2007+) files.

gdata: Run the function 'installXLSXsupport()'
gdata: to automatically download and install the perl
gdata: libaries needed to support Excel XLS and XLSX formats.

Attaching package: ‘gdata’

The following object is masked from ‘package:stats’:

    nobs

The following object is masked from ‘package:utils’:

    object.size

The following object is masked from ‘package:base’:

    startsWith

Warning message:
In system(cmd, intern = TRUE) :
  running command ''/usr/bin/perl' '/usr/lib/R/site-library/gdata/perl/supportedFormats.pl'' had status 126
    Sepal.Length Sepal.Width Petal.Length Petal.Width   Species
143          5.8         2.7          5.1         1.9 virginica
    Sepal.Length Sepal.Width Petal.Length Petal.Width   Species
102          5.8         2.7          5.1         1.9 virginica
    Sepal.Length Sepal.Width Petal.Length Petal.Width   Species
102          5.8         2.7          5.1         1.9 virginica
143          5.8         2.7          5.1         1.9 virginica

gdata documentation built on May 2, 2019, 5:49 p.m.