[R] argument rationalization
rksh at soc.soton.ac.uk
Mon Nov 15 09:44:12 CET 2004
I am writing a bunch of functions that take two, three or four
arguments. These functions operate on vectors of the same length;
but I want the function
to behave sensibly if one or more arguments are scalars. "+" does
this for two arguments:
"+"(1:10,3) # interpreted as "+"(1:10,rep(3,10))
But my functions can take more arguments. Say f() takes three:
f(1:10,1:10,1:10) # default
f(3,1:10,1:10) # interpret as f(rep(3,10),1:10,1:10)
f(1:10,3,1:10) # interpret as f(1:10,rep(3,10),1:10)
f(1:10,3,5) # interpret as f(1:10,rep(3,10),rep(5,10))
and h() takes four:
h(2,4,5,1:10) # interpret as h(rep(2,10),rep(4,10),rep(5,10),1:10)
h(2,3,1:10,1) # interpret as h(rep(2,10),rep(3,10),1:10,rep(1:10)
h(1:20,3,1:20,1) # interpret as h(1:20,rep(3,20),1:20,rep(1,20))
I haven't got any that need five yet, but this may change in the future.
How do I implement this desired behaviour nicely?
(I pass the arguments to .C(), which is why I need this).
Southampton Oceanography Centre
initialDOTsurname at soc.soton.ac.uk (edit in obvious way; spam precaution)
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