Question

我有两个数据集，如下df1和df2。我希望通过匹配df和df1$pkg将两者合并为一个df2$name。但df1$pkg和df2$name中的字符串并不完全相同。我尝试使用agrep，但这不起作用。将不胜感激任何帮助。

x<-agrep(df1[,2], df2[,1],ignore.case=T, value=T)
Warning message:
In agrep(df1[, 2], df2[, 1], ignore.case = T, value = T) :
  argument 'pattern' has length > 1 and only the first element will be used
> x
character(0)



df1<<-data.frame(apname=c("photo eff pro", "olx", "firefox", "word search", "chrome","bbc news"), 
             pkg=c("bbc.mobile.news", "com.dhqsolutions", "#com.olx.olx","org.mozilla.firefox","ws.letras", "com.chrome"),
             apcat=c(5,3,4,5,4,1))
df2<-data.frame(name=c("bbc.mob.news.ww", "com.dhqsolutions.enjoyphoto", "com.olx.olx","org.mozilla.firefox","ws.letras","chrome.approximated"),
            tic=c(10000, 12345, 123456, 23456,9903, 12389034))

Answer 1

您将要使用apply系列函数（see this excellent Q&A）或某种类型的循环。这就是您收到警告信息的原因。考虑这个简单的例子：

vec1 <- c("Dog", "Cat", "Pony")
vec2 <- c("catty", "doggy", "fish", "ponyt")
sapply(vec1, agrep, vec2)
# Dog  Cat  Pony 
#   2    1     4

在您的情况下，您可能希望执行以下操作：sapply(df1$pkg, agrep, df2$name)

使用R中的部分字符串匹配合并两个数据集

1 个答案: