This package defines a function applyBy that enables applying a function along margins of matrixlike objects separately within groups of columns/rows defined by factor(s), e.g., computing aggregated summary statistics. It is essentially a wrapper around functions from the the matrixStats package, which provide very fast alternative implementation to the base aggregate function.
Package details 


Maintainer  
License  GPL (>= 2) 
Version  1.2 
Package repository  View on GitHub 
Installation 
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