RFC: spline / splinefun (etc) amalgamation
Martin Maechler
Martin Maechler <maechler@stat.math.ethz.ch>
Tue, 26 May 1998 08:58:52 +0200
>>>>> "KH" == Kurt Hornik <Kurt.Hornik@ci.tuwien.ac.at> writes:
>>>>> Ross Ihaka writes:
>> At present R has separate functions "spline" and "splinefun". The
>> first of these carries out spline interpolation of a data set and
>> returns the interpolated values; the second returns the
>> interpolating function itself (approx and approxfun are similar).
>> I would like to combine these into a single function "spline" with
>> an (optional) argument which determines which kind of value is
>> returned. E.g.
>> spline(x,y) # return interpolated function spline(x,y,fun=T) #
>> return the interpolating function
>> I would also like to propose this as a standard for smoothing and
>> interpolating functions. This has a couple of advantages - fewer
>> names to remember and, the ability to use the function form in model
>> fitting code ("predict" for example).
>> Any objections or comments?
Very good idea [including the "standard"!]
KH> Perhaps smoothing.or.interpolating.fun(data) should in general
KH> return the FUNCTION (more precisely, a function object of an
KH> appropriate class), and the values would be obtained via predict()?
I do prefer Ross' version:
1. For a novice or average user, it is more intuitive to get a list /
data.frame as a result by default.
2. compatibility
KH> (May not be BBC, though ...)
yes
3. The ($x, $y) list is simpler AND smaller (in memory).
Martin
-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-
r-devel mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html
Send "info", "help", or "[un]subscribe"
(in the "body", not the subject !) To: r-devel-request@stat.math.ethz.ch
_._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._