What's the most elegant way to extract the last word in a sentence string?
提取句子字符串中最后一个单词的最优雅方法是什么?
The sentence does not end with a "." Words are seperated by blanks.
句子不以“。”结尾。单词由空格分隔。
sentence <- "The quick brown fox"
TheFunction(sentence)
should return: "fox"
应该回归:“狐狸”
I do not want to use a package if a simple solution is possible. If a simple solution based on package exists, that is also fine.
如果可以使用简单的解决方案,我不想使用包。如果存在基于包的简单解决方案,那也没关系。
5 个解决方案
#1
17
tail(strsplit('this is a sentence',split=" ")[[1]],1)
Basically as suggested by @Señor O.
基本上是@SeñorO的建议。
#2
37
Just for completeness: The library stringr contains a function for exactly this problem.
只是为了完整性:库字符串包含一个完全解决此问题的函数。
library(stringr)
sentence <- "The quick brown fox"
word(sentence,-1)
[1] "fox"
#3
11
x <- 'The quick brown fox'
sub('^.* ([[:alnum:]]+)$', '\\1', x)
That will catch the last string of numbers and characters before then end of the string.
这将捕获字符串之前的最后一串数字和字符。
You can also use the regexec
and regmatches
functions, but I find sub
cleaner:
你也可以使用regexec和regmatches函数,但我找到sub cleaner:
m <- regexec('^.* ([[:alnum:]]+)$', x)
regmatches(x, m)
See ?regex
and ?sub
for more info.
有关详细信息,请参阅?regex和?sub。
#4
11
Another packaged option is stri_extract_last_words()
from the stringi
package
另一个打包选项是stringi包中的stri_extract_last_words()
library(stringi)
stri_extract_last_words("The quick brown fox")
# [1] "fox"
The function also removes any punctuation that may be at the end of the sentence.
该函数还删除可能在句子末尾的任何标点符号。
stri_extract_last_words("The quick brown fox? ...")
# [1] "fox"
#5
5
Going in the package direction, this is the simplest answer I can think of:
顺便提一下,这是我能想到的最简单的答案:
library(stringr)
x <- 'The quick brown fox'
str_extract(x, '\\w+$')
#[1] "fox"
#1
17
tail(strsplit('this is a sentence',split=" ")[[1]],1)
Basically as suggested by @Señor O.
基本上是@SeñorO的建议。
#2
37
Just for completeness: The library stringr contains a function for exactly this problem.
只是为了完整性:库字符串包含一个完全解决此问题的函数。
library(stringr)
sentence <- "The quick brown fox"
word(sentence,-1)
[1] "fox"
#3
11
x <- 'The quick brown fox'
sub('^.* ([[:alnum:]]+)$', '\\1', x)
That will catch the last string of numbers and characters before then end of the string.
这将捕获字符串之前的最后一串数字和字符。
You can also use the regexec
and regmatches
functions, but I find sub
cleaner:
你也可以使用regexec和regmatches函数,但我找到sub cleaner:
m <- regexec('^.* ([[:alnum:]]+)$', x)
regmatches(x, m)
See ?regex
and ?sub
for more info.
有关详细信息,请参阅?regex和?sub。
#4
11
Another packaged option is stri_extract_last_words()
from the stringi
package
另一个打包选项是stringi包中的stri_extract_last_words()
library(stringi)
stri_extract_last_words("The quick brown fox")
# [1] "fox"
The function also removes any punctuation that may be at the end of the sentence.
该函数还删除可能在句子末尾的任何标点符号。
stri_extract_last_words("The quick brown fox? ...")
# [1] "fox"
#5
5
Going in the package direction, this is the simplest answer I can think of:
顺便提一下,这是我能想到的最简单的答案:
library(stringr)
x <- 'The quick brown fox'
str_extract(x, '\\w+$')
#[1] "fox"