gsub

How do you limit the number of replacements made by String#gsub in Ruby? In PHP this can be easy done with preg_replace which takes a parameter for limiting replacements, but I can't figure out how to do this in Ruby. gsub replaces all occurences. You can try String#sub http://ruby-doc.org/core/classes/String.html#M001185 You can create a counter and decrement that within a gsub loop. str = 'aaaaaaaaaa' count = 5 p str.gsub(/a/){if count.zero? then $& else count -= 1; 'x' end} # => "xxxxxaaaaa" str = 'aaaaaaaaaa' # The following is so that the variable new_string exists in this scope, # not

I read a file: local logfile = io.open("log.txt", "r") data = logfile:read("*a") print(data) output: ... "(\.)\n(\w)", r"\1 \2" "\n[^\t]", "", x, re.S ... Yes, logfile looks awful as it's full of various commands How can I call gsub and remove i.e. "(\.)\n(\w)", r"\1 \2" line from data variable? Below snippet, does not work: s='"(\.)\n(\w)", r"\1 \2"' data=data:gsub(s, '') I guess some escaping needs to be done. Any easy solution? Update : local data = [["(\.)\n(\w)", r"\1 \2" "\n[^\t]", "", x, re.S]] local s = [["(\.)\n(\w)", r"\1 \2"]] local function esc(x) return (x:gsub('%%', '%%%%') :gsub

How to use gsub with more than 9 backreferences? I would expect the output in the example below to be "e, g, i, j, o". > test <- "abcdefghijklmnop" > gsub("(\\w)(\\w)(\\w)(\\w)(\\w)(\\w)(\\w)(\\w)(\\w)(\\w)(\\w)(\\w)(\\w)(\\w)(\\w)(\\w)", "\\5, \\7, \\9, \\10, \\15", test, perl = TRUE) [1] "e, g, i, a0, a5" See Regular Expressions with The R Language : You can use the backreferences \1 through \9 in the replacement text to reinsert text matched by a capturing group . There is no replacement text token for the overall match. Place the entire regex in a capturing group and then use \1 . But with

I have csv file contents having double quotes inside quoted text test,first,line,"you are a "kind" man",thanks again,second,li,"my "boss" is you",good I need to replace every double quote not preceded or succeeded by a comma by "" test,first,line,"you are a ""kind"" man",thanks again,second,li,"my ""boss"" is you",good so " is replaced by "" I tried x.gsub(/([^,])"([^,])/, "#{$1}\"\"#{$2}") but didn't work Phrogz Your regex needs to be a little more bold, in case the quotes occur at the start of the first value, or at the end of the last value: csv = <<ENDCSV test,first,line,"you are a "kind"

I'm working on a Text Mining Solution with SQL and R. First I Import Data into R from my SQL selection and than I do data mining stuff with it. Here is what I got: rawData = sqlQuery(dwhConnect,sqlString) a = data.frame(rawData$ENNOTE_NEU) If I do a a[[1]][1:3] you see the structure: [1] lorem ipsum li ld ee wö wo di dd [2] la kdin di da dogs chicken [3] kd good i need some help Now I want to do some data cleaning with my own dictionary. An Example would be to replace li with lorem ipsum and kd as well as kdin with kunde My Problem is how to do that for the whole Data Frame. for(i in 1:(nrow(a