strwrapx: Wrap strings at white space and + symbols

Description Usage Arguments Details Examples

View source: R/mle.R

Description

Extended (hacked) version of strwrap: wraps a string at whitespace and plus symbols

Usage

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strwrapx(x, width = 0.9 * getOption("width"), indent = 0,
exdent = 0, prefix = "", simplify = TRUE,
parsplit = "\n[ \t\n]*\n", wordsplit = "[ \t\n]")

Arguments

x

a character vector, or an object which can be converted to a character vector by as.character.

width

a positive integer giving the target column for wrapping lines in the output.

indent

a non-negative integer giving the indentation of the first line in a paragraph.

exdent

a non-negative integer specifying the indentation of subsequent lines in paragraphs.

prefix

a character string to be used as prefix for each line.

simplify

a logical. If TRUE, the result is a single character vector of line text; otherwise, it is a list of the same length as x the elements of which are character vectors of line text obtained from the corresponding element of x. (Hence, the result in the former case is obtained by unlisting that of the latter.)

parsplit

Regular expression describing how to split paragraphs

wordsplit

Regular expression decribing how to split words

Details

Whitespace in the input is destroyed. Double spaces after periods (thought as representing sentence ends) are preserved. Currently, possible sentence ends at line breaks are not considered specially.

Indentation is relative to the number of characters in the prefix string.

Examples

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## Read in file 'THANKS'.
x <- paste(readLines(file.path(R.home("doc"), "THANKS")), collapse = "\n")
## Split into paragraphs and remove the first three ones
x <- unlist(strsplit(x, "\n[ \t\n]*\n"))[-(1:3)]
## Join the rest
x <- paste(x, collapse = "\n\n")
## Now for some fun:
writeLines(strwrap(x, width = 60))
writeLines(strwrap(x, width = 60, indent = 5))
writeLines(strwrap(x, width = 60, exdent = 5))
writeLines(strwrap(x, prefix = "THANKS> "))

## Note that messages are wrapped AT the target column indicated by
## 'width' (and not beyond it).
## From an R-devel posting by J. Hosking <[email protected]>.
x <- paste(sapply(sample(10, 100, rep=TRUE),
           function(x) substring("aaaaaaaaaa", 1, x)), collapse = " ")
sapply(10:40,
       function(m)
       c(target = m, actual = max(nchar(strwrap(x, m)))))

bbmle documentation built on Nov. 17, 2017, 6:42 a.m.