[R] locate word in vector

[Chuck Cleland]

kevinchang wrote:
> Hey All,
> 
> 
> I am wondering if there is a built-in function allowing us to locate a
> particular word in a character vector.
> 
> ex: vector a
> 
> a
> [1] "superman"  "xamn"      "spiderman" "superman"  "superman"  "xman"     
> [7] "spiderman"
> 
> Is there any built-in function that can show "superman" are the first,
> fourth and fifith element in "a"? Please help me out. Thanks. 

a <- c("superman", "xamn", "spiderman", "superman",
       "superman", "xman", "spiderman")

grep("^superman$", a)
[1] 1 4 5

?grep

OR

which(a %in% "superman")
[1] 1 4 5

?which
?is.element

-- 
Chuck Cleland, Ph.D.
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