strsplit

I have the following string: Getty <- "Four score and seven years ago our fathers brought forth on this continent a new nation, conceived in liberty, and dedicated to the proposition that all men are created equal." I want to display the first 10 characters. So I began by splitting the string into individual characters: split <- strsplit(Getty, split="") split I get all the individual characters as this point. Then I make a substring of the first 10 characters. first.10 <- substr(split, start=1, stop=10) first.10 And here is the output: "c(\"F\", \"o\"" I am not understanding why this prints

I am trying to extract the part of the string before the first backslash but I can't seem to get it tot work properly. I have tried multiple ways of getting it to work, based on the manual page for strsplit and after searching online. In my actual situation the strings are in a dataframe which I get from a database connection but I can simplify the situation with the following: > strsplit("BLAAT1\022E:\\BLAAT2\\BLAAT3","\\",fixed=TRUE) [[1]] [1] "BLAAT1\022E:" "BLAAT2" "BLAAT3" > strsplit("BLAAT1\022E:\\BLAAT2\\BLAAT3","\\",fixed=FALSE) Error in strsplit("BLAAT1\022E:\\BLAAT2\\BLAAT3", "\\",

I have a data table with one string column. I'd like to create another column that is a subset of this column using strsplit. dat <- data.table(labels=c('a_1','b_2','c_3','d_4')) The output I want is label sub_label a_1 a b_2 b c_3 c d_4 d I've tried the followings but neither seems to work. dat %>% mutate( sub_labels=strsplit(as.character(labels), "_")[[1]][1] ) # gives a column whose values are all "a" this one, which seems logical to me, dat %>% mutate( sub_labels=sapply(strsplit(as.character(labels), "_"), function(x) x[[1]][1]) ) gives an error Error: Don't know how to handle type

I'm trying to use strsplit() in R to break a string into pieces based on commas, but I don't want to split up anything in parentheses. I think the answer is a regex but I'm struggling to get the code right. So for example: x <- "This is it, isn't it (well, yes)" > strsplit(x, ", ") [[1]] [1] "This is it" "isn't it (well" "yes)" When what I would like is: [1] "This is it" "isn't it (well, yes)" akrun We can use PCRE regex to FAIL any , that follows that a ( before the ) and split by , followed by 0 or more space ( \\s* ) strsplit(x, '\\([^)]+,(*SKIP)(*FAIL)|,\\s*', perl=TRUE)[[1]] #[1] "This is

A comment on my answer to this question which should give the desired result using strsplit does not, even though it seems to correctly match the first and last commas in a character vector. This can be proved using gregexpr and regmatches . So why does strsplit split on each comma in this example, even though regmatches only returns two matches for the same regex? # We would like to split on the first comma and # the last comma (positions 4 and 13 in this string) x <- "123,34,56,78,90" # Splits on every comma. Must be wrong. strsplit( x , '^\\w+\\K,|,(?=\\w+$)' , perl = TRUE )[[1]] #[1] "123"

This works x <- "0.466:1.187:2.216:1.196" y <- as.numeric(unlist(strsplit(x, ":"))) Values of blat$LRwAvg all look like X above but this doesn't work for (i in 1:50){ y <- as.numeric(unlist(strsplit(blat$LRwAvg[i], "\\:"))) blat$meanLRwAvg[i]=mean(y) } Because of: Error in strsplit(blat$LRwAvg[i], "\:") : non-character argument It doesn't matter if I have one, two or null backslashes. What's my problem? (Not generally, I mean in this special task, technically) As agstudy implied blat$LRwAvg <- as.character(blat$LRwAvg) before loop fixed it blat$meanLRwAvg <- blat$gtFrqAvg #or some other

When creating functions that use strsplit , vector inputs do not behave as desired, and sapply needs to be used. This is due to the list output that strsplit produces. Is there a way to vectorize the process - that is, the function produces the correct element in the list for each of the elements of the input? For example, to count the lengths of words in a character vector: words <- c("a","quick","brown","fox") > length(strsplit(words,"")) [1] 4 # The number of words (length of the list) > length(strsplit(words,"")[[1]]) [1] 1 # The length of the first word only > sapply(words,function (x)