AMR/man/like.Rd

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% Generated by roxygen2: do not edit by hand
% Please edit documentation in R/like.R
\name{like}
\alias{like}
\alias{\%like\%}
\alias{\%like_case\%}
\title{Pattern Matching}
\source{
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Idea from the \href{https://github.com/Rdatatable/data.table/blob/master/R/like.R}{\code{like} function from the \code{data.table} package}
}
\usage{
like(x, pattern, ignore.case = TRUE)
x \%like\% pattern
x \%like_case\% pattern
}
\arguments{
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\item{x}{a character vector where matches are sought, or an object which can be coerced by \code{\link[=as.character]{as.character()}} to a character vector.}
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\item{pattern}{a character string containing a regular expression (or \code{\link{character}} string for \code{fixed = TRUE}) to be matched in the given character vector. Coerced by \code{\link[=as.character]{as.character()}} to a character string if possible. If a \code{\link{character}} vector of length 2 or more is supplied, the first element is used with a warning.}
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\item{ignore.case}{if \code{FALSE}, the pattern matching is \emph{case sensitive} and if \code{TRUE}, case is ignored during matching.}
}
\value{
A \code{\link{logical}} vector
}
\description{
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Convenient wrapper around \code{\link[=grep]{grep()}} to match a pattern: \code{x \%like\% pattern}. It always returns a \code{\link{logical}} vector and is always case-insensitive (use \code{x \%like_case\% pattern} for case-sensitive matching). Also, \code{pattern} can be as long as \code{x} to compare items of each index in both vectors, or they both can have the same length to iterate over all cases.
}
\details{
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The \verb{\%like\%} function:
\itemize{
\item Is case insensitive (use \verb{\%like_case\%} for case-sensitive matching)
\item Supports multiple patterns
\item Checks if \code{pattern} is a regular expression and sets \code{fixed = TRUE} if not, to greatly improve speed
\item Tries again with \code{perl = TRUE} if regex fails
}
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Using RStudio? This function can also be inserted from the Addins menu and can have its own Keyboard Shortcut like \code{Ctrl+Shift+L} or \code{Cmd+Shift+L} (see \code{Tools} > \verb{Modify Keyboard Shortcuts...}).
}
\section{Stable lifecycle}{
\if{html}{\figure{lifecycle_stable.svg}{options: style=margin-bottom:5px} \cr}
The \link[AMR:lifecycle]{lifecycle} of this function is \strong{stable}. In a stable function, we are largely happy with the unlying code, and major changes are unlikely. This means that the unlying code will generally evolve by adding new arguments; we will avoid removing arguments or changing the meaning of existing arguments.
If the unlying code needs breaking changes, they will occur gradually. To begin with, the function or argument will be deprecated; it will continue to work but will emit an message informing you of the change. Next, typically after at least one newly released version on CRAN, the message will be transformed to an error.
}
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\section{Read more on our website!}{
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On our website \url{https://msberends.gitlab.io/AMR} you can find \href{https://msberends.gitlab.io/AMR/articles/AMR.html}{a comprehensive tutorial} about how to conduct AMR analysis, the \href{https://msberends.gitlab.io/AMR/reference}{complete documentation of all functions} (which reads a lot easier than here in R) and \href{https://msberends.gitlab.io/AMR/articles/WHONET.html}{an example analysis using WHONET data}.
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}
\examples{
# simple test
a <- "This is a test"
b <- "TEST"
a \%like\% b
#> TRUE
b \%like\% a
#> FALSE
# also supports multiple patterns, length must be equal to x
a <- c("Test case", "Something different", "Yet another thing")
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b <- c( "case", "diff", "yet")
a \%like\% b
#> TRUE TRUE TRUE
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# get isolates whose name start with 'Ent' or 'ent'
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\dontrun{
library(dplyr)
example_isolates \%>\%
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filter(mo_name(mo) \%like\% "^ent") \%>\%
freq(mo)
}
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}
\seealso{
\code{\link[base:grep]{base::grep()}}
}