Question

我有一个名为cars的字符串，如下所示：

cars
[1] "Only one car(52;model-14557) had a good engine(workable condition), others engine were damaged beyond repair"   
[2] "Other car(21, model-155) looked in good condition but car ( 36, model-8878) looked to be in terrible condition."

我需要从字符串中提取以下部分：

car(52;model-14557)
car(21, model-155)
car ( 36, model-8878)

我尝试使用以下的一部分来提取它：

stringr::str_extract_all(cars, "(.car\\s{0,5}\\(([^]]+)\\))")

这给了我以下输出：

[[1]]
[1] " car(52;model-14557) had a good engine(workable condition)"

[[2]]
[1] " car(21, model-155) looked in good condition but car ( 36, model-8878)"

有没有办法可以提取带有相关编号和型号的汽车一词？

Answer 1

Your regex does not work因为您使用[^]]+，]以外的一个或多个符号与(和)匹配，因此匹配来自( ) {1}}直到最后]，其间没有> cars <- c("Only one car(52;model-14557) had a good engine(workable condition), others engine were damaged beyond repair","Other car(21, model-155) looked in good condition but car ( 36, model-8878) looked to be in terrible condition.") > library(stringr) > str_extract_all(cars, "\\bcar\\s*\\([^()]+\\)") [[1]] [1] "car(52;model-14557)" [[2]] [1] "car(21, model-155)" "car ( 36, model-8878)"。

使用

\bcar\s*\([^()]+\)

正则表达式为\b，请参阅online regex demo here。

匹配：

car - 字边界
\s* - 文字字符序列
\( - 0+ whitespaces
( - 文字[^()]+
( - 除)和\)以外的一个或多个字符
) - 文字> regmatches(cars, gregexpr("\\bcar\\s*\\([^()]+\\)", cars)) [[1]] [1] "car(52;model-14557)" [[2]] [1] "car(21, model-155)" "car ( 36, model-8878)"。

请注意，相同的正则表达式将使用以下基本R代码产生相同的结果：

<a href="{{calendar.url}}" target="_blank">{{ 'Home.calendar.readMore' | translate }} <i class="fa fa-angle-right"></i></a>

正则表达式直到第一次出现括号关闭

1 个答案: