How to Strsplit Using '|' Character, It Behaves Unexpectedly

How to strsplit using '|' character, it behaves unexpectedly?

The problem is that by default strsplit interprets " | " as a regular expression, in which | has special meaning (as "or").

Use fixed argument:

unlist(strsplit("I am | very smart", " | ", fixed=TRUE))
# [1] "I am"       "very smart"

Side effect is faster computation.

stringr alternative:

unlist(stringr::str_split("I am | very smart", fixed(" | ")))

strsplit with vertical bar (pipe)

As you can read on ?strsplit, the argument split in function strsplit is a regular expression. Hence either you need to escape the vertical bar (it is a special character)

strsplit(r,split='\\|and')

or you can choose fixed=TRUE to indicate that split is not a regular expression

strsplit(r,split='|and',fixed=TRUE)

R splitting string based on double-character delimiter

We can wrap with fixed as | is a metacharacter for OR

library(stringr)
str_split(myString, fixed("||"))[[1]]
#[1] "Test"  "Test1" "test2"

Or another option is to escape (\\ - as @joran mentioned in the comments) or place it inside a square bracket

data

myString <- "Test||Test1||test2"

Using strsplit wid pipe separator in R

Just needs to add to backslash before the bar:

strsplit(x, "\\|")

For example:

> x <- "Hello | Could you help me please?"
> strsplit(x, "\\|")
[[1]]
[1] "Hello "                     " Could you help me please?"

Splitting string with pipe character ( | )

| is a metacharacter in regex. You'd need to escape it:

String[] value_split = rat_values.split("\\|");

Split string into key-value pairs

You could do a single call to split() and a single pass on the String using the following code. But it of course assumes the String is valid in the first place:

    Map<String, String> map = new HashMap<String, String>();
    String test = "pet:cat::car:honda::location:Japan::food:sushi";

    // split on ':' and on '::'
    String[] parts = test.split("::?");

    for (int i = 0; i < parts.length; i += 2) {
        map.put(parts[i], parts[i + 1]);
    }

    for (String s : map.keySet()) {
        System.out.println(s + " is " + map.get(s));
    }

The above is probably a little bit more efficient than your solution, but if you find your code clearer, then keep it, because there is almost zero chance such an optimization has a significant impact on performance, unless you do that millions of times. Anyway, if it's so important, then you should measure and compare.

EDIT:

for those who wonder what ::? means in the above code: String.split() takes a regular expression as argument. A separator is a substring that matches the regular expression. ::? is a regular expression which means: 1 colon, followed by 0 or 1 colon. It thus allows considering :: and : as separators.

How to use strsplit() to access elements in an R list?

A "tidyverse" approach similar to suggestion in comments by @GavinSimpson:

library(purrr)
library(stringr)

x <- rep("stringA, stringB", 10)

str_split(x, ", ") %>% map_chr(`[`, 2)
#>  [1] "stringB" "stringB" "stringB" "stringB" "stringB" "stringB" "stringB"
#>  [8] "stringB" "stringB" "stringB"

• str_split() acts like strsplit().
• map_chr() acts like lapply(), but also converts resulting list to a character vector.

For your problem, substitute x for list1$field2

How do I replace all occurrences of a string in JavaScript?

In the latest versions of most popular browsers, you can use replaceAll
as shown here:

let result = "1 abc 2 abc 3".replaceAll("abc", "xyz");
// `result` is "1 xyz 2 xyz 3"

But check Can I use or another compatibility table first to make sure the browsers you're targeting have added support for it first.

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For Node.js and compatibility with older/non-current browsers:

Note: Don't use the following solution in performance critical code.

As an alternative to regular expressions for a simple literal string, you could use

str = "Test abc test test abc test...".split("abc").join("");

The general pattern is

str.split(search).join(replacement)

This used to be faster in some cases than using replaceAll and a regular expression, but that doesn't seem to be the case anymore in modern browsers.

Benchmark: https://jsben.ch/TZYzj

Conclusion:

If you have a performance-critical use case (e.g., processing hundreds of strings), use the regular expression method. But for most typical use cases, this is well worth not having to worry about special characters.

Library (stringr) doesn't work for |

 str_replace_all(dts$Campaign, "[|]", "")

Splitting String based on letters case

Just do this. It works by (a) locating an upper case letter, (b) capturing it in a group and (c) replacing it with the same with a space preceding it.

gsub('([[:upper:]])', ' \\1', x)

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