如何从R中的字符串中的多个列表中检测子字符串 [英] How to detect substrings from multiple lists within a string in R

问题描述

我正在尝试查找名为"values"的字符串是否包含来自两个不同列表的子字符串.这是我当前的代码:

I am attempting to try and find if a string called "values" contains substrings from two different lists. This is my current code:

for (i in 1:length(value)){
  for (j in 1:length(city)){
    if (str_detect(value[i],(city[j]))) == TRUE){
        for (k in 1:length(school)){
            if (str_detect(value[i],(school[j]))) == TRUE){
        ...........................................................
        }
      }
    }
  }
}

city和school是长度不同的单独向量，每个向量都包含字符串元素.

city and school are separate vectors of different length, each containing string elements.

city <- ("Madrid", "London", "Paris", "Sofia", "Cairo", "Detroit", "New York")
school <- ("Law", "Mathematics", "PoliSci", "Economics")
value <- ("Rey Juan Carlos Law Dept, Madrid", "New York University, Center of PoliSci Studies", ..........)

我想做的是查看value是否包含来自两个列表的元素的某种组合，以供以后使用.可以一步完成吗:像这样:

What I want to do is see if value contains some combination of elements from both lists to later work with that. Can this be done in a single step: something like this:

for (i in 1:length(value)){
    if (str_detect(value[i],(city[j]))) == TRUE && str_detect(value[i],(school[j]))) == TRUE){
                   .............................................
    }
}

推荐答案

尝试一下:

library("stringr")

city <- c("Madrid", "London", "Paris", "Sofia", "Cairo", "Detroit", "New York")
school <- c("Law", "Mathematics", "PoliSci", "Economics")
value <- c(
  "Rey Juan Carlos Law Dept, Madrid",
  "New York University, Center of PoliSci Studies",
  "Los Angeles, CALTECH",
  "London, Physics",
  "London, Mathematics"
      )

for (v in value)
{
  if (sum(str_detect(v, city)) > 0 & sum(str_detect(v, school)) > 0)
  {
    print (v)
  }
}

执行时，将打印与城市和学校具有共同元素的内容:

when executed it will print those which have common element with city and school:

[1] "Rey Juan Carlos Law Dept, Madrid"
[1] "New York University, Center of PoliSci Studies"
[1] "London, Mathematics"

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