- string
- grep("Pole",c("Equator","North Pole","South Pole"))
- 2 3
- grep("pole",c("Equator","North Pole","South Pole"))
- integer(0)
- nchar("South Pole")
- 10
- paste("North","Pole",sep="")
- "NorthPole"
- i<-8
- sprintf("the square of %d is %d",i,i^2) # format print
- substring("Equator",3,5) # "uat"
- strsplit("6-16-2011",split="-")
- [[1]]
- "6" "16" "2011"
- regexpr("uat","Equator")
- 3
- grepexpr("iss","Mississippi")
- 2 5 # find all occurrances
- grep("[au]",c("Equator","North Pole","South Pole"))
- 1 3 # word contains a or u
- grep("o.e",c("Equator","North Pole","South Pole"))
- 2 3 # word contains o+any char+e
- grep("\\.",c("abc","de","f.g")) # escape
- 3
- testsuffix<-function(fn,suff) {
- parts<-strsplit(fn,".",fixed=TRUE) # or strsplit(fn,"\\.")
- nparts<-length(parts[[1]]) # split length
- return(parts[[1]][nparts]==suff)
- }
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