如何删除R中没有大写字母的单词？

Question

我在做使用R.文本分析有没有办法删除所有的话不是在盖使用tm或stringi？

如果我有这样的事情

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

被转换成

Albert Einstein Nikola Tesla

最好的祝福

Answer 1

您可以使用简单的正则表达式删除这些单词

gsub("\\b[a-z]+\\s+", "", x)
# [1] "Albert Einstein Nikola Tesla"

这只是寻找一个单词边界>小写字母>后面的所有字母>它后面的所有空格并删除它

虽然如果你有这样的词don't,你需要更复杂的正则表达式.就像是

x <- "if Albert Einstein didn't see his friend Nikola Tesla leavin'"
gsub("\\b[a-z][^ ]*(\\s+)?", "", x)
# [1] "Albert Einstein Nikola Tesla "

Answer 2

只需使用grep和正则表达式:

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=' ')