[R] matching a string with multiple conditions using grep

[Rui Barradas]

Hello,

Try the following.


wanted <- c("A_cont_12", "AB_cont_22", "cont_21_Aa")

x <- c("A_cont_1", "A_cont_12", "B_treat_8", "AB_cont_22", "cont_21_Aa")

pattern <- c("A", "cont", "2")

ix <- Reduce(`&`, lapply(pattern, grepl, x))  # This does the trick
identical(wanted, x[ix])


See ?Reduce.

Hope this helps,

Rui Barradas

Em 23-06-2012 11:19, Zhipeng Wang escreveu:
> Suppose I have a vector  ["A_cont_1", "A_cont_12", "B_treat_8",
> "AB_cont_22", "cont_21_Aa"], I hope I can extract the strings which include
> 3 short strings, say "A", "cont" and "2",  that is to say, "A_cont_12",
> "AB_cont_22" and  "cont_21_Aa" will be extract, using a relatively short
> code (using grep?).
> Would you please to give some idea? Thank you !
>
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