stringr

Assume 900+ company names pasted together to form a regex pattern using the pipe separator -- "firm.pat". firm.pat <- str_c(firms$firm, collapse = "|") With a data frame called "bio" that has a large character variable (250 rows each with 100+ words) named "comment", I would like to replace all the company names with blanks. Both a gsub call and a str_replace_all call return the same mysterious error. bio$comment <- gsub(pattern = firm.pat, x = bio$comment, replacement = "") Error in gsub(pattern = firm.pat, x = bio$comment, replacement = "") : assertion 'tree->num_tags == num_tags' failed in

I read up on regular expressions and Hadley Wickham's stringr and dplyr packages but can't figure out how to get this to work. I have library circulation data in a data frame, with the call number as a character variable. I'd like to take the initial capital letters and make that a new variable and the digits between the letters and period into a second new variable. Call_Num HV5822.H4 C47 Circulating Collection, 3rd Floor QE511.4 .G53 1982 Circulating Collection, 3rd Floor TL515 .M63 Circulating Collection, 3rd Floor D753 .F4 Circulating Collection, 3rd Floor DB89.F7 D4 Circulating Collection

I am trying to count the number of appearances of a substring within a character vector. For example: lookin<-c("babababa", "bellow", "ra;baba") searchfor<-"aba" str_count(lookin, searchfor) returns: 2 0 1 However, I want it to return '3 0 1' but it isn't picking up on the middle 'aba' in the first item since it is partially used in the first instance (I think). I found this question but couldn't figure out how to use that with a vector having multiple items. Try: str_count(lookin, paste0("(?=",searchfor,")")) [1] 3 0 1 Which, as answered in your link, uses lookahead to match all instances. 来源

I have data where the words as follows location<- c("xyz, sss, New Zealand", "USA", "Pris,France") id<- c(1,2,3) df<-data.frame(location,id) I would like to extract the country name from the data. The tricky part is if i extract just the last word then I will have only one record (France). library(stringr) df$country<- word(df$location,-1) Any ideas on how to extract country data from this data? id location country 1 xyz, sss, New Zealand New Zealand 2 USA USA 3 Pris,France France You can try sub df$country <- sub('.*,\\s*', '', df$location) df$country #[1] "New Zealand" "USA" "France" Or

Two related questions. I have vectors of text data such as "a(b)jk(p)" "ipq" "e(ijkl)" and want to easily separate it into a vector containing the text OUTSIDE the parentheses: "ajk" "ipq" "e" and a vector containing the text INSIDE the parentheses: "bp" "" "ijkl" Is there any easy way to do this? An added difficulty is that these can get quite large and have a large (unlimited) number of parentheses. Thus, I can't simply grab text "pre/post" the parentheses and need a smarter solution. Text outside the parenthesis > x <- c("a(b)jk(p)" ,"ipq" , "e(ijkl)") > gsub("\\([^()]*\\)", "", x) [1] "ajk

I'm looking to extract the year from a string. This always comes after an 'X' and before "." then a string of other characters. Using stringr 's str_extract I'm trying the following: year = str_extract(string = 'X2015.XML.Outgoing.pounds..millions.' , pattern = 'X(\\d{4})\\.') I thought the brackets would define the capture group, returning 2015 , but I actually get the complete match X2015. Am I doing this correctly? Why am i not trimming "X" and "."? The capture group is irrelevant in this case. The function str_extract will return the whole match including characters before and after the

I don't seem to see a difference between paste / paste0 and str_c for combining a single vector into a single string, multiple strings into one string, or multiple vectors into a single string. While I was writing the question I found this: https://www.rdocumentation.org/packages/stringr/versions/1.3.1/topics/str_c . The community example from richie@datacamp.com says the difference is is that str_c treats blanks as blanks (not as NAs) and recycles more appropriately. Any other differences? paste0(..., collapse = NULL) is a wrapper for paste(..., sep = "", collapse = NULL) , which means there