How do I speed up text searches in R?

Question

I have a large text vector I would like to search for a particular character or phrase. Regular expressions are taking forever. How do I search it quickly?

Sample

Answer 1

There's no need for regular expressions here, and their power comes with a computational cost.

You can turn off regular expression parsing in any of the regex functions in R with the ,fixed=TRUE argument. Speed gains result:

library(microbenchmark)
m <- microbenchmark( 
    grep( " ", garbage, fixed=TRUE ),
    grep( " ", garbage )
)
m
Unit: milliseconds
                             expr       min        lq   median        uq      max neval
 grep(" ", garbage, fixed = TRUE)  491.5634  497.1309  499.109  503.3009 1128.643   100
               grep(" ", garbage) 1786.8500 1801.9837 1810.294 1825.2755 3620.346   100