Regex “提取”之后的文本&引用；

我有一根绳子

x <- "Name of the Student? Michael Sneider"

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但无法提取名称。

我认为这应该会有所帮助

substr(x, str_locate(x, "?")+1, nchar(x))

试试这个：

sub('.*\\?(.*)','\\1',x)

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str\u match

在这种情况下更有用

str_match(x, ".*\\?\\s(.*)")[, 2] 
#[1] "Michael Sneider"

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x为了利用问题的松散措辞，我们可以走得太远，使用自然语言处理从字符串中提取所有名称：

library(openNLP)
library(NLP)
# you'll also have to install the models with the next line, if you haven't already
# install.packages('openNLPmodels.en', repos = 'http://datacube.wu.ac.at/', type = 'source')

s <- as.String(x)    # convert x to NLP package's String object

# make annotators
sent_token_annotator <- Maxent_Sent_Token_Annotator()
word_token_annotator <- Maxent_Word_Token_Annotator()
entity_annotator <- Maxent_Entity_Annotator()

# call sentence and word annotators
s_annotated <- annotate(s, list(sent_token_annotator, word_token_annotator))
# call entity annotator (which defaults to "person") and subset the string
s[entity_annotator(s, s_annotated)]
## Michael Sneider

库（openNLP）
图书馆（NLP）
#如果您还没有安装，您还必须在下一行中安装模型
#install.packages（'openNLPmodels.en'，repos='http://datacube.wu.ac.at/，类型='source'）
s
x <- "Name of the Student? Michael Sneider"

sub(pattern = ".+?\\?" , x , replacement = '' )

library(openNLP)
library(NLP)
# you'll also have to install the models with the next line, if you haven't already
# install.packages('openNLPmodels.en', repos = 'http://datacube.wu.ac.at/', type = 'source')

s <- as.String(x)    # convert x to NLP package's String object

# make annotators
sent_token_annotator <- Maxent_Sent_Token_Annotator()
word_token_annotator <- Maxent_Word_Token_Annotator()
entity_annotator <- Maxent_Entity_Annotator()

# call sentence and word annotators
s_annotated <- annotate(s, list(sent_token_annotator, word_token_annotator))
# call entity annotator (which defaults to "person") and subset the string
s[entity_annotator(s, s_annotated)]
## Michael Sneider