I have a string like this:
myString <- "[0.15][4577896]blahblahblahblahwhatever"
I need to extract the number between second brackets.
Currently I am trying to use this:
str_extract(myString, "\\]\\[(\\d+)")
But this gives me ][4577896
My desired result would be: 4577896
How could I achieve this?
With no need of look behinds
gsub(".*\\[(\\d+).*","\\1",myString)
[1] "4577896"
Here is another version with minimal or no regex
qdapRegex::ex_between_multiple(myString, "[", "]")[[2]]
#[1] "4577896"
It extracts all the substring between [ and ] and we select the value between second bracket. You can convert it into numeric or integer if needed.
You may use
^(?:[^\[\]]*\[[^\[\]]+\])[^\]\[]*\[([^\]\[]+).+
And replace this with the first captured group using gsub, see a demo on regex101.com.
In base R:
myString <- "[0.15][4577896]blahblahblahblahwhatever"
pattern <- "^(?:[^\\[\\]]*\\[[^\\[\\]]+\\])[^\\]\\[]*\\[([^\\]\\[]+).+"
gsub(pattern, "\\1", myString, perl = T)
# [1] "4577896"
An option using str_extract
library(stringr)
str_extract(myString, "(?<=.\\[)([0-9]+)")
#[1] "4577896"
stringr::str_extract(myString, "(?<=\\]\\[)(\\d+)")