根据重叠模式删除字符串的一部分

Uwe在问题下的注释中提到了带有str_locate_all的新选项，这大大简化了代码：

library(stringr)
# Create function to remove matching part of text
# First argument is text, second argument is a list of start and length 
remove_matching_parts <- function(text, positions) {
  if (nrow(positions) == 0) return(text)
  ret <- strsplit(text,"")[[1]]
  lapply(1:nrow(positions), function(x) { ret[ positions[x,1]:positions[x,2] ] <<- NA } )
  paste0(ret[!is.na(ret)],separator="",collapse="")
}

# Loop over the data to apply the pattern
# row = length of vector, columns = length of pattern
matches <- lapply(dat$x, function(x) {
  do.call(rbind,str_locate_all(x, my_patterns)) # transform the list output of str_locate in a table of start/end
})

# Avoid growing a vector in a for loop, create it beforehand, it will be the same length as teh vector we work against
dat$result <- vector("character",length(dat$x))
# Loop on each value to remove the matching parts
for (i in 1:length(dat$x)) {
 dat$result[i] <- remove_matching_parts(as.character(dat$x[i]),matches[[i]])
}

如果您可以控制模式定义并可以手动创建，则可以使用正则表达式解决方案来实现：

> gsub("(is )?my (other text|example)?","",dat$x)
[1] "this  text"        "and here  example" " is short" 

这个想法是创建带有可选部分的模式（?在分组括号之后）。

因此，我们大致有：

• (is )? <=可选的“是”，后跟空格
• my <=文字“ my”后跟空格
• (other text|example)?<=在“我的”之后的可选文本，可以是“其他文本”或|“示例”

如果您没有控制权，事情就会变得混乱，我希望我已经对其进行了充分的评论，使其易于理解，根据其中包含的循环数量，不要指望它会很快：

# Given datas
dat <- data.frame(x               = c("this is my example text", "and here is my other text example", "my other text is short","yet another text"),
                some_other_cols = c(1, 2, 2, 4))

my_patterns <- c("my example", "is my", "my other text")

# Create function to remove matching part of text
# First argument is text, second argument is a list of start and length 
remove_matching_parts <- function(text, positions) {
  ret <- strsplit(text,"")[[1]]
  lapply(positions, function(x) { ifelse(is.na(x),,ret[ x[1]:x[2] ] <<- NA ) } )
  paste0(ret[!is.na(ret)],separator="",collapse="")
}

# Create the matches between a vector and a pattern
# First argument is the pattern to match, second is the vector of charcaters
match_pat_to_vector <- function(pattern,vector) {
  sapply(regexec(pattern,vector), 
         function(x) {
           if(x>-1) { 
             c(start=as.numeric(x), end=as.numeric(x+attr(x,"match.length")) ) # Create a start/end vector from the index and length of the match
           }
         })
}

# Loop over the patterns to create a dataframe of matches
# row = length of vector, columns = length of pattern
matches <- sapply(my_patterns,match_pat_to_vector,vector=dat$x)

# Avoid growing a vector in a for loop, create it beforehand, it will be the same length as teh vector we work against
dat$result <- vector("character",length(dat$x))
# Loop on each value to remove the matching parts
for (i in 1:length(dat$x)) {
 dat$result[i] <- remove_matching_parts(as.character(dat$x[i]),matches[i,])
}

运行后结果：

> dat
                                  x some_other_cols           result
1           this is my example text               1        this text
2 and here is my other text example               2 and here example
3            my other text is short               2         is short
4                  yet another text               4 yet another text