Я новичок в R и пытаюсь выяснить, есть ли способ упростить следующий код
assault<-"13"
drugs<-"35"
homicide<-"09"
kidnapping<-"10"
sex_offense<-"36"
sex_assault<-"11"
theft<-c("12","22","23","24","28")
crime_data$OffenseType<-ifelse((substr(crime_data$NCIC.CODE,1,2) %in% assault)==TRUE,"Assault",
ifelse((substr(crime_data$NCIC.CODE,1,2) %in% drugs)==TRUE,"Drugs",
ifelse((substr(crime_data$NCIC.CODE,1,2) %in% homicide)==TRUE,"Homicide",
ifelse((substr(crime_data$NCIC.CODE,1,2) %in% kidnapping)==TRUE,"Kidnapping",
ifelse((substr(crime_data$NCIC.CODE,1,2) %in% sex_offense)==TRUE,"Sexual Offense",
ifelse((substr(crime_data$NCIC.CODE,1,2) %in% sex_assault)==TRUE,"Sexual Assault",
ifelse((substr(crime_data$NCIC.CODE,1,2) %in% theft)==TRUE,"Theft","Others")))))))