[R] grep for multiple pattern?

[Rainer M Krug]

Hi

I want to search for multiple pattern as grep is doing for a single
pattern, but this obviously not work:

> grep("an", month.name)
[1] 1
> grep("em", month.name)
[1]  9 11 12
> grep("eb", month.name)
[1] 2
> grep(c("an", "em", "eb"), month.name)
[1] 1
Warning message:
In grep(c("an", "em", "eb"), month.name) :
  argument 'pattern' has length > 1 and only the first element will be used
>

Is there an equivalent which returns the positions as grep is doing, but
not using the strict full-string matching of match()?

I could obviously do:

> unlist( sapply(pat, grep, month.name ) )
 an em1 em2 em3  eb
  1   9  11  12   2

but is there a more compact command I am missing?

Thanks,

Rainer

-- 
Rainer M. Krug, PhD (Conservation Ecology, SUN), MSc (Conservation
Biology, UCT), Dipl. Phys. (Germany)

Centre of Excellence for Invasion Biology
Stellenbosch University
South Africa

Tel :       +33 - (0)9 53 10 27 44
Cell:       +33 - (0)6 85 62 59 98
Fax :       +33 - (0)9 58 10 27 44

Fax (D):    +49 - (0)3 21 21 25 22 44

email:      Rainer at krugs.de

Skype:      RMkrug

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