Pattern matching in r (grep and grepl)
Pattern matching in r (grep and grepl)
grep and grepl commands are used for pattern matching in r.
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grep_result <- grep("a", c("a", "b", "c", "d"))
class(grep_result)
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[1] "integer"
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grep_result
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[1] 1
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grepl_result <- grepl("a", c("a", "b", "c", "d"))
class(grepl_result)
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[1] "logical"
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grepl_result
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[1] TRUE FALSE FALSE FALSE
grep returns a integer vector (index).
grepl returns a logical vector (boolean).
Summary for grep and grepl
grep |
grepl |
|
|---|---|---|
| Return | integer index | logical |
References:
RDocumentation grep: Pattern Matching and Replacement