[R] Aggregate function for comparison stats

[Neil Davis]

Hi,

I have a data.frame which contains timeseries from several different 
locations, which I want to compare against each other for example 
calculating RMSE, or normalized mean bias of each location against the 
others. An example of this is the cor function where I can put in a 
data.frame and get the correlation of each location compared to the 
others in the data.frame eg.
cor(data.frame(a=runif(10),b=runif(10),c=runif(10),d=runif(10)))

Is there any generic way of getting this for other functions, such as 
the aggregate or lapply functions? I have read their documentation, but 
was unclear as to how I might use them to get a matrix like the cor 
function. I could do this using a pair of loops, but was hoping there 
might be a more general way of creating such a matrix of any comparison 
function.

Thank you for your help,

-- 

Neil Davis
Ph.d.-student
DTU Wind Energy

Technical University of Denmark

	
Department of Wind Energy
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