adopt man pages for ncp->linear change

DESCRIPTION

 Package: akima
-Version: 0.4-5
-Date: 2005-07-21
+Version: 0.5-1
+Date: 2006-02-01
 Title: Interpolation of irregularly spaced data
 Author: Fortran code by H. Akima
  R port by Albrecht Gebhardt <albrecht.gebhardt@uni-klu.ac.at>

man/akima.Rd

@@ -50,7 +50,7 @@ rgl.points(akima.p$x,akima.p$z , akima.p$y,size=4,color="yellow")
 # data
 rgl.spheres(akima$x,akima$z , akima$y,0.5,color="red")
 rgl.bbox()
-# bivariate linear interpolation
+# bivariate cubic spline interpolation
 # interp:
 akima.si <- interp(akima$x, akima$y, akima$z, 
                    xo=seq(min(akima$x), max(akima$x), length = 100),

man/interp.Rd

@@ -56,14 +56,15 @@ interp.new(x, y, z, xo = seq(min(x), max(x), length = 40),
   \item{linear}{logical -- indicating wether linear or spline
     interpolation should be used. supersedes old \code{ncp} parameter}
   \item{ncp}{
-    deprecated, use parameter \code{linear}.
+    deprecated, use parameter \code{linear}. Now only used by 
+    \code{interp.old()}.
 
     meaning was:
     number of additional points to be used in computing partial
     derivatives at each data point.
     \code{ncp} must be either \code{0} (partial derivatives are not used), or at
     least 2 but smaller than the number of data points (and smaller than
-    25). This option is only supported by \code{interp.old}.
+    25).
   }
   \item{extrap}{
     logical flag: should extrapolation be used outside of the
@@ -100,20 +101,22 @@ interp.new(x, y, z, xo = seq(min(x), max(x), length = 40),
   interpolation the old version is choosen, but spline interpolation is
   done by the new version.
 
-  At the moment \code{interp.new} ignores \code{ncp} and does only
-  bicubic spline interpolation.
+  Earlier versions (pre 0.5-1) of \code{interp} used the parameter 
+  \code{ncp} to choose between linear and cubic interpolation, this is now done
+  by setting the logical parameter \code{linear}. Use of \code{ncp} is still 
+  possible, but is deprecated.
 
   The resulting structure is suitable for input to the
   functions \code{contour} and \code{image}.  Check the requirements of
   these functions when choosing values  for \code{xo} and \code{yo}.
 }
 \details{
-  If \code{ncp} is zero, linear
+  If \code{linear} is \code{TRUE} (default), linear
   interpolation is used in the triangles bounded by data points.
-  Cubic interpolation is done if partial derivatives are used.
+  Cubic interpolation is done if \code{linear} is set to \code{FALSE}.
   If \code{extrap} is \code{FALSE}, z-values for points outside the
   convex hull are returned as \code{NA}.
-  No extrapolation can be performed if \code{ncp} is zero.
+  No extrapolation can be performed for the linear case.
 
   The \code{interp} function handles duplicate \code{(x,y)} points
   in different ways. As default it will stop with an error message. But
@@ -172,8 +175,8 @@ image  (akima.part)
 contour(akima.part, add=TRUE)
 points(akima$x[1:15],akima$y[1:15])
 
-## spline interpolation
-## --------------------
+## spline interpolation, two variants (AMS 526 "Old", AMS 761 "New")
+## -----------------------------------------------------------------
 ## "Old": use 5 points to calculate derivatives -> many NAs
 akima.sO <- interp.old(akima$x, akima$y, akima$z,
            xo=seq(0,25, length=100),  yo=seq(0,20, length=100), ncp=5)
@@ -187,6 +190,11 @@ contour(akima.sO, add = TRUE)
 ## "New:"
 akima.spl <- with(akima, interp.new(x,y,z, xo=seq(0,25, length=100),
                                            yo=seq(0,20, length=100)))
+## equivalent call via setting linear=FALSE in interp():
+akima.spl <- with(akima, interp(x,y,z, xo=seq(0,25, length=100),
+                                       yo=seq(0,20, length=100),
+                                linear=FALSE))
+
 contour(akima.spl) ; points(akima)
 
 full.pal <- function(n) hcl(h = seq(340, 20, length = n))
@@ -204,9 +212,10 @@ data(airquality)
 air <- subset(airquality,
               !is.na(Temp) & !is.na(Ozone) & !is.na(Solar.R))
 # gives an error {duplicate ..}:
-try( air.ip <- interp.new(air$Temp,air$Solar.R,air$Ozone) )
+try( air.ip <- interp(air$Temp,air$Solar.R,air$Ozone, linear=FALSE) )
 # use mean of duplicate points:
-air.ip <- with(air, interp.new(Temp, Solar.R, log(Ozone), duplicate = "mean"))
+air.ip <- with(air, interp(Temp, Solar.R, log(Ozone), duplicate = "mean",
+                           linear = FALSE))
 image(air.ip, main = "Airquality: Ozone vs. Temp and Solar.R")
 with(air, points(Temp, Solar.R))
 }

man/interpp.Rd

@@ -37,7 +37,8 @@ dupfun = NULL, ncp)
   \item{linear}{logical -- indicating wether linear or spline
     interpolation should be used. supersedes old \code{ncp} parameter}
   \item{ncp}{
-    deprecated, use parameter \code{linear}.
+    deprecated, use parameter \code{linear}. Now only used by 
+    \code{interpp.old()}.
 
     meaning was:
     number of additional points to be used in computing partial
@@ -79,10 +80,15 @@ dupfun = NULL, ncp)
   Use \code{interp} if interpolation on a regular grid is wanted.
 
   The two versions  \code{interpp.old}  and \code{interpp.new} refer to
-  Akimas Fortran code from 1978 and 1996 resp. At the moment
-  \code{interpp.new}
-  does not work porperly (it results in a segmentation fault), so it is
-  not used from the call wrapper  \code{interp}.
+  Akimas Fortran code from 1978 and 1996 resp. The call wrapper  \code{interpp}
+  chooses  \code{interpp.old} for linear and  \code{interpp.new} for cubic 
+  spline interpolation.
+
+  Earlier versions (pre 0.5-1) of \code{interpp} used the parameter 
+  \code{ncp} to choose between linear and cubic interpolation, this is now done
+  by setting the logical parameter \code{linear}. Use of \code{ncp} is still 
+  possible, but is deprecated.
+
 }
 \description{
   If \code{ncp} is zero, linear
@@ -122,8 +128,8 @@ data(akima)
 akima.lip<-interpp(akima$x, akima$y, akima$z,c(1,5,10),c(2,6,12))
 akima.lip$z
 # spline interpolation
-akima.lip<-interpp(akima$x, akima$y, akima$z,c(1,5,10),c(2,6,12),
+akima.sip<-interpp(akima$x, akima$y, akima$z,c(1,5,10),c(2,6,12),
   linear=FALSE)
-akima.lip$z
+akima.sip$z
 }
 \keyword{dplot}