Question

我有以下数据框

patientID<-c(1,2,3,4,5,6,7,8)
age<-c(25,30,28,52,45,26,36,32)
s<-c("m","w","w","m","w","w","m","w")
diabetes<-c("T1","T2","T2","T3","T1","T2","T1","T1")
status<-c("poor","ïmproved","poor","ïmproved","Excellent","poor","ïmproved","Excellent")
patientenData<-data.frame(patientID,age,diabetes,status,s)

并且想要编写如下过滤器

filter<-c(s=="m","age>28","OR",s=="w","age>38")
filter<-paste(filter,collapse="&")
filter<-gsub("&OR&","|",filter)
patientenData<-patientenData[with(patientenData,eval(parse(text=filter))),]

问题是，为了能够执行最后一部分，我需要一个＆＃34;字符串的字符串＆＃34;。我的意思是

filter<-c("s=="m"","age>28","OR","s=="w"","age>38")

因为parse和eval。但这并不容易。我也尝试了toString和is.character或as.character，但没有成功。谢谢你的每一个提示。

Answer 1

data.table包是一个更好的方法：

library(data.table)
patientID<-c(1,2,3,4,5,6,7,8)
age<-c(25,30,28,52,45,26,36,32)
s<-c("m","w","w","m","w","w","m","w")
diabetes<-c("T1","T2","T2","T3","T1","T2","T1","T1")
status<-c("poor","ïmproved","poor","ïmproved","Excellent","poor","ïmproved","Excellent")
patientenData<-data.table(patientID,age,diabetes,status,s)

作为data.table，您可以编写类似查询的SQL

filtered<-patientenData[s=='m' & age>28 | s =='w'&age>38]

Answer 2

来自subset()的{{1}}：

{base}

带索引：

filtered <- subset(patientenData, s=='m' & age>28 | s =='w' & age>38)

如何在R中有一串字符串？

2 个答案: