R数据框架字符串包含:第1列是否包含第2列？

Question

我有一个包含两列的数据框:

  Surname                Email
1   house  greghouse@gmail.com
2  wilson johnwatson@gmail.com

我想创建一个逻辑向量来检查是否Surname包含在中Email.结果应该是:

  Surname                Email CheckEmail
1   house  greghouse@gmail.com       TRUE
2  wilson johnwatson@gmail.com      FALSE

我试过grep但似乎grep只能在一个或多个实例中查找一个模式.我特别需要在多个实例中查找多个模式.

> grep(df1$Surname,df1$Email)
[1] 1
Warning message:
In grep(df1$Surname, df1$Email) :
  argument 'pattern' has length > 1 and only the first element will be used

Answer 1

尝试使用library("stringi")和:

df1$CheckEmail <- stri_detect_fixed(df1$Email, df1$Surname)

Answer 2

下面是一个使用基础R的方法mapply有grepl:

transform(df, CheckEmail = mapply(grepl, Surname, Email))
#  Surname                Email CheckEmail
#1   house  greghouse@gmail.com       TRUE
#2  wilson johnwatson@gmail.com      FALSE