Power functions?
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On Sat, 3 Jan 2009, rkevinburton at charter.net wrote:
I had a question about the basic power functions in R. For example from the R console I enter: -1 ^ 2 [1] -1 but also -1^3 [1] -1 -0.1^2 [1] -0.01 Normally pow(-1, 2) return either -Infinity or NaN. Has R taken over the math functions? If so I would think that -1^2 is 1 not -1 and -0.1^2 is 0.01 not -0.01.
See ?Syntax, linked from ?`^` :
The following unary and binary operators are defined. They are
listed in precedence groups, from highest to lowest.
'[ [[' indexing
':: :::' access variables in a name space
'$ @' component / slot extraction
'^' exponentiation (right to left)
'- +' unary minus and plus
so -1^2 is -(1^2) not (-1)^2.
Brian D. Ripley, ripley at stats.ox.ac.uk Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/ University of Oxford, Tel: +44 1865 272861 (self) 1 South Parks Road, +44 1865 272866 (PA) Oxford OX1 3TG, UK Fax: +44 1865 272595