[R] maximum of identical elements in a vector

[Daniel Malter]

Thanks to all who responded so quickly.

-------------------------
cuncta stricte discussurus
-------------------------

-----Ursprüngliche Nachricht-----
Von: Chuck Cleland [mailto:ccleland at optonline.net] 
Gesendet: Sunday, March 30, 2008 5:45 PM
An: Daniel Malter
Cc: r-help at stat.math.ethz.ch
Betreff: Re: [R] maximum of identical elements in a vector

On 3/30/2008 5:35 PM, Daniel Malter wrote:
> Hi,
> 
> the problem I have is seemingly very simple, but not simple enough for 
> me to figure out. I just want to find the most (or least) frequent 
> element in the vector.
> 
> a=c("Alice","Alice","Alice","Alice","Bob","Bob")
> unique(a)
> length(which(a=="Alice"))
> 
> 
> unique(a) shows me that the elements in my vector are "Alice" and 
> "Bob". The latter expression gives 4 as the frequency of "Alice" in vector
a.
> To find the maximum frequency of the unique elements, however, it 
> assumes that I know that "Alice" is the most (or least) frequent 
> element. Therefore, how can find that "Alice" is the most frequent 
> element in this vector? I assume there is an easier way than 
> computationally intensive loops (for long vectors).

 > names(which.max(table(a)))
[1] "Alice"

> Cheers,
> Daniel
> 
> -------------------------
> cuncta stricte discussurus
> 
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