Question

说我有这样的文字：

pattern = "This_is some word/expression I'd like to parse:intelligently(using special symbols-like '.')"

挑战在于如何使用

中的单词分隔符将其拆分为单词

c(" ","-","/","\\","_",":","(",")",".",",")

家族。

期望的结果：

"This" "is" "some" "word" "expression" "I'd" "like" "to" "parse" "intelligently" "using" "special" "symbols" "like"

方法：

我可以使用

进行sapply或for循环

 keywords = unlist(strsplit(pattern," "))
 keywords = unlist(strsplit(keywords,"-"))

＃etc。

问题：

但使用Reduce(f, x, init, accummulate=TRUE)的解决方案是什么？

Answer 1

你在这里不应该Reduce。您应该可以执行以下操作：

splitters <- c(" ","/","\\","_",":","(",")",".",",","-") # dash should come last
pattern <- paste0("[", paste(splitters, collapse = ""), "]")
string <- "This_is some word/expression I'd like to parse:intelligently(using special symbols-like '.')"
strsplit(string, pattern)[[1]]
#  [1] "This"          "is"            "some"          "word"         
#  [5] "expression"    "I'd"           "like"          "to"           
#  [9] "parse"         "intelligently" "using"         "special"      
# [13] "symbols"       "like"          "'"             "'"

请注意，正则表达式字符类中的-应该是第一个或最后一个，所以我已经编辑了＆＃34;分割器＆＃34;因此。此外，您可能希望在＆＃34;模式结束时添加+＆＃34;如果您想要将多个空格折叠成一个。

Answer 2

您可以使用选项perl = TRUE然后拆分标点符号或空格

> strsplit(pattern, '[[:punct:]]|[[:space:]]', perl = TRUE)
[[1]]
 [1] "This"          "is"            "some"          "word"          "expression"   
 [6] "I"             "d"             "like"          "to"            "parse"        
[11] "intelligently" "using"         "special"       "symbols"       "like"         
[16] ""

Answer 3

我一起去（它将"I'd"保持在一起）

strsplit(pattern, "[^[:alnum:][:digit:]']")
## [[1]]
##  [1] "This"          "is"            "some"          "word"          "expression"    "I'd"           "like"          "to"            "parse"        
## [10] "intelligently" "using"         "special"       "symbols"       "like"          "'"             "'"

递归拆分字符串

3 个答案: