stringr

I would like to filter a dataframe using filter() and str_detect() matching for multiple patterns without multiple str_detect() function calls. In the example below I would like to filter the dataframe df to show only rows containing the letters a f and o . df <- data.frame(numbers = 1:52, letters = letters) df %>% filter( str_detect(.$letters, "a")| str_detect(.$letters, "f")| str_detect(.$letters, "o") ) # numbers letters #1 1 a #2 6 f #3 15 o #4 27 a #5 32 f #6 41 o I have attempted the following df %>% filter( str_detect(.$letters, c("a", "f", "o")) ) # numbers letters #1 1 a #2 15 o #3 32

Unfortunately I suck at regexp. If I have a path like so: /long/path/to/file , I just need to extact file . If someone supplies file/ I just need file . If someone supplies /file/ , I still need just file . I've been using stringr functions as a crutch but this seems like straight up grep territory. Help, please? If I understand correctly, you could use the basename function. f <- "/long/path/to/file" basename(f) # [1] "file" What about this? > path <- "/long/path/to/file" > require(stringr) > str_extract(path, "[^/]*$") [1] "file" 来源： https://stackoverflow.com/questions/9693877/how-do-i

I have a string, say fruit <- "()goodapple" I want to remove the brackets in the string. I decide to use stringr package because it usually can handle this kind of issues. I use : str_replace(fruit,"()","") But nothing is replaced, and the following is replaced: [1] "()good" If I only want to replace the right half bracket, it works: str_replace(fruit,")","") [1] "(good" However, the left half bracket does not work: str_replace(fruit,"(","") and the following error is shown: Error in sub("(", "", "()good", fixed = FALSE, ignore.case = FALSE, perl = FALSE) : invalid regular expression '(',

I have a list comprised of words. > head(splitWords2) [[1]] [1] "Some" "additional" "information" "that" "we" "would" "need" "to" "replicate" "the" [11] "experiment" "is" "how" "much" "vinegar" "should" "be" "placed" "in" "each" [21] "identical" "container" "or" "what" "tool" "use" "measure" "mass" "of" "four" [31] "different" "samples" "and" "distilled" "water" "rinse" "after" "taking" "them" "out" [[2]] [1] "After" "reading" "the" "expirement" "I" "realized" "that" "additional" "information" "you" [11] "need" "to" "replicate" "expireiment" "is" "one" "amant" "of" "vinegar" "poured" [21] "in"

I am trying to use the stringr library to extract emails from a big, messy file. str_match doesn't allow perl=TRUE, and I can't figure out the escape characters to get it to work. Can someone recommend a relatively robust regex that would work in the context below? c("larry@gmail.com", "larry-sally@sally.com", "larry@sally.larry.com")->emails "SomeRegex"->regex str_match(emails, regex) 42- > "^[[:alnum:].-_]+@[[:alnum:].-]+$"->regex > str_match(emails, regex) [,1] [1,] "larry@gmail.com" [2,] "larry-sally@sally.com" [3,] "larry@sally.larry.com" The @-sign is not in need of escaping in regex.