[R] Wildcard for indexing?

[Johannes Radinger]

Hi,

I'd like to know if it is possible to use wildcards * for indexing...
E.g. I have a vector of strings. Now I'd like to select all elements
which start with A_*? I'd also need to combine that with logical operators:

"Select all elements of a vector that start with A (A*) OR that start with B (B*)"

Probably that is quite easy. I looked into grep() which I think might perform such tasks, but probably there is a more straigth forward solution.

a <- c("A_A","A_B","C_A","BB","A_Asd")
a[a=="A_A"| a=="A_B"] # here I'd like an index but with wildcard

/johannes
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