CODEWITHSUNDEEP
regexr
K2xL
K2xL

Reputation: 10270

Regmatches in R not working

I am trying to add a column to a data set in R. The column should be the initials from a name column. I am trying to use lapply and passing in a function to get the initials - however, I can't get this regexp to work.

pattern <- "(\b[a-zA-Z])"
str<-"MICHAEL,  JENSON F"
m <- regexpr(pattern,str,perl=TRUE)
regmatches(str,m)

Returns character(0)

How can I have R return a list of matches of a string? I want regmatches to return M J and F.

Upvotes: 0

Views: 1679

Answers (2)

Julius Vainora
Julius Vainora

Reputation: 48201

There are two problems: \b must be escaped and you should use gregexpr instead of regexpr because the latter returns only the first match.

pattern <- "(\\b[a-zA-Z])"
str<-"MICHAEL,  JENSON F"
m <- gregexpr(pattern,str,perl=TRUE)
regmatches(str,m)[[1]]
# [1] "M" "J" "F"

Upvotes: 4

K2xL
K2xL

Reputation: 10270

Just figured out the stringr library.

str_match_all(str, "(\\b[a-zA-Z])[a-zA-Z]* ?")

Upvotes: 2

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