How to remove words not in caps in R?

Question

I'm doing text analysis using R. Is there a way to remove all the words not in caps using tm or stringi?

If I have something like this

Albert Einstein went to the store and saw his friend Nikola Tesla ... + 200 pags

to be converted into

Albert Einstein Nikola Tesla

Best regards

Answer 1

Just use grep and a regular expression:

words <- 'Albert Einstein went to the store and saw his friend Nikola Tesla'

# split to vector of individual words
vec <- unlist(strsplit(words, ' '))
# just the capitalized ones
caps <- grep('^[A-Z]', vec, value = T)
# assemble back to a single string, if you want
paste(caps, collapse=' ')