Detect a Pattern Match
These functions determine, for each string in str,
if there is at least one match to a corresponding pattern.
stri_detect(str, ..., regex, fixed, coll, charclass) stri_detect_fixed( str, pattern, negate = FALSE, max_count = -1, ..., opts_fixed = NULL ) stri_detect_charclass(str, pattern, negate = FALSE, max_count = -1) stri_detect_coll( str, pattern, negate = FALSE, max_count = -1, ..., opts_collator = NULL ) stri_detect_regex( str, pattern, negate = FALSE, max_count = -1, ..., opts_regex = NULL )
str |
character vector; strings to search in |
... |
supplementary arguments passed to the underlying functions,
including additional settings for |
pattern, regex, fixed, coll, charclass |
character vector; search patterns; for more details refer to stringi-search |
negate |
single logical value; whether a no-match to a pattern is rather of interest |
max_count |
single integer; allows to stop searching once a given
number of occurrences is detected; |
opts_collator, opts_fixed, opts_regex |
a named list used to tune up
the search engine's settings; see
|
Vectorized over str and pattern (with recycling
of the elements in the shorter vector if necessary). This allows to,
for instance, search for one pattern in each given string,
search for each pattern in one given string,
and search for the i-th pattern within the i-th string.
If pattern is empty, then the result is NA
and a warning is generated.
stri_detect is a convenience function.
It calls either stri_detect_regex,
stri_detect_fixed, stri_detect_coll,
or stri_detect_charclass, depending on the argument used.
See also stri_startswith and stri_endswith
for testing whether a string starts or ends with a match to a given pattern.
Moreover, see stri_subset for a character vector subsetting.
If max_count is negative, then all stings are examined.
Otherwise, searching terminates
once max_count matches (or, if negate is TRUE,
no-matches) are detected. The uninspected cases are marked
as missing in the return vector. Be aware that, unless pattern is a
singleton, the elements in str might be inspected in a
non-consecutive order.
Each function returns a logical vector.
Other search_detect:
about_search,
stri_startswith()
stri_detect_fixed(c('stringi R', 'R STRINGI', '123'), c('i', 'R', '0'))
stri_detect_fixed(c('stringi R', 'R STRINGI', '123'), 'R')
stri_detect_charclass(c('stRRRingi','R STRINGI', '123'),
c('\\p{Ll}', '\\p{Lu}', '\\p{Zs}'))
stri_detect_regex(c('stringi R', 'R STRINGI', '123'), 'R.')
stri_detect_regex(c('stringi R', 'R STRINGI', '123'), '[[:alpha:]]*?')
stri_detect_regex(c('stringi R', 'R STRINGI', '123'), '[a-zC1]')
stri_detect_regex(c('stringi R', 'R STRINGI', '123'), '( R|RE)')
stri_detect_regex('stringi', 'STRING.', case_insensitive=TRUE)
stri_detect_regex(c('abc', 'def', '123', 'ghi', '456', '789', 'jkl'),
'^[0-9]+$', max_count=1)
stri_detect_regex(c('abc', 'def', '123', 'ghi', '456', '789', 'jkl'),
'^[0-9]+$', max_count=2)
stri_detect_regex(c('abc', 'def', '123', 'ghi', '456', '789', 'jkl'),
'^[0-9]+$', negate=TRUE, max_count=3)Please choose more modern alternatives, such as Google Chrome or Mozilla Firefox.