R: Extract entries from a BibEntry object by index

[[.BibEntry {RefManageR} | R Documentation

## Extract entries from a BibEntry object by index

### Description

Operator for extracting BibEntry objects by index.

### Usage

    ## S3 method for class 'BibEntry'
    x[[i, drop = FALSE]]

### Arguments

`x` | a BibEntry object
`i` | numeric indices of entries to extract, or a character vector of keys corresponding to the entries to be extracted.
`drop` | logical, should attributes besides class be dropped from result?

### Value

an object of class BibEntry.

### Note

This method is different than the usual operator `[[` for lists in that a vector of indices may be specified.

This method behaves differently than the `[` operator for BibEntry objects in that it does not expand crossreferences when returning, so that a parent entry or xdata entry will be dropped if it is not also indexed when indexing the child entry.

This method is not affected by the value of `BibOptions()$return.ind`.

### See Also

Other operators: `$.BibEntry`, `$<-.BibEntry`, `+.BibEntry`, `[.BibEntry`, `[<-.BibEntry`, `[[<-.BibEntry`, `c.BibEntry`

### Examples

    file.name <- system.file("Bib", "biblatexExamples.bib", package="RefManageR")
    bib <- suppressMessages(ReadBib(file.name))
    bib[[20:21]]
    bib[c("hyman", "loh")]

    ## Note this is FALSE because [[ does not inherit from the dropped parent entry while [ does.
    identical(bib[1], bib[[1]])

[Package RefManageR version 1.2.0 Index]