detecting word boundary with regex in data frame in R

dataframe, r, regex, word-boundary

Solution

In R, you need two times `\`:

grep("\\bword\\b", all[5])

Alternative solutions:

grep("^word$", all[5])

which(all[5] == "word")

Problem

I have a data.frame named `all` that has a column of factors, these factors include `"word"`,`"nonword"` and some others. My goal is to select only the rows that have the factor value "word". My solution `grep("\bword\b",all[,5])` returns nothing. How come word boundaries are not recognized?

Original source

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