从 R 中用户定义的语料库中删除停用词

我有一组文件：

documents = c("She had toast for breakfast",
 "The coffee this morning was excellent", 
 "For lunch let's all have pancakes", 
 "Later in the day, there will be more talks", 
 "The talks on the first day were great", 
 "The second day should have good presentations too")

在这组文档中，我想删除停用词。我已经删除了标点符号并转换为小写，使用：

documents = tolower(documents) #make it lower case
documents = gsub('[[:punct:]]', '', documents) #remove punctuation

首先我转换为 Corpus 对象：

documents <- Corpus(VectorSource(documents))

然后我尝试删除停用词：

documents = tm_map(documents, removeWords, stopwords('english')) #remove stopwords

但最后一行会导致以下错误：

THE_PROCESS_HAS_FORKED_AND_YOU_CANNOT_USE_THIS_COREFOUNDATION_FUNCTIONALITY___YOU_MUST_EXEC() 进行调试。

这已经被问过here https://stackoverflow.com/questions/18688599/the-process-has-forked-error-while-using-tm-package-in-r但没有给出答复。这个错误是什么意思？

EDIT

是的，我正在使用 tm 包。

这是 sessionInfo() 的输出：

R版本3.0.2 (2013-09-25) 平台：x86_64-apple-darwin10.8.0（64位）

当我遇到tm问题 我经常最终只是编辑原始文本。

要删除单词有点尴尬，但您可以将正则表达式粘贴在一起tm的停用词列表。

stopwords_regex = paste(stopwords('en'), collapse = '\\b|\\b')
stopwords_regex = paste0('\\b', stopwords_regex, '\\b')
documents = stringr::str_replace_all(documents, stopwords_regex, '')

> documents
[1] "     toast  breakfast"             " coffee  morning  excellent"      
[3] " lunch lets   pancakes"            "later   day  will   talks"        
[5] " talks   first day  great"         " second day   good presentations "