How to configure the pattern inside the grep function to exclude "CTT_OMT"?
txt<-c("OAT","HST","OCT","OMT","CTT","CTT_OMT")
grep("[OACM]T$",txt,value = T)
[1] "OAT" "OCT" "OMT" "CTT_OMT"
> grep("[OACMT{2}]",txt,value = T)
[1] "OAT" "HST" "OCT" "OMT" "CTT" "CTT_OMT"
> grep("[OACMT{2}]",txt,value = T)
[1] "OAT" "HST" "OCT" "OMT" "CTT" "CTT_OMT"
> grep("[OACMT{1,2}]",txt,value = T)
[1] "OAT" "HST" "OCT" "OMT" "CTT" "CTT_OMT"
> grep("[OACMT^_]",txt,value = T)
[1] "OAT" "HST" "OCT" "OMT" "CTT" "CTT_OMT"
> grep("[OACMT^.]",txt,value = T)
[1] "OAT" "HST" "OCT" "OMT" "CTT" "CTT_OMT"
the desired result is:
"OAT" "OCT" "OMT" "CTT"
Gracias