interpolation using akima (PR#8174)
This message should be sent to the package maintainer, not to this list. Moreover, it works fine with my installation (i.e., I don't get the bug you describe): R: platform i386-pc-mingw32 arch i386 os mingw32 system i386, mingw32 status beta major 2 minor 2.0 year 2005 month 09 day 24 svn rev 35666 language R akima: Package: akima Version: 0.4-5 Date: 2005-07-21 Best, Renaud 2005/10/3, jonathan_lees at unc.edu <jonathan_lees at unc.edu>:
Full_Name: Jonathan Lees
Version: 2.0.1
OS: linux-gnu
Submission from: (NULL) (152.2.75.65)
there is a problem with calculating the convex hull in 2-D interpolation using
the codes interp fromt eh akima package:
x =c(0.6505304, -1.1821562, -0.2600792, 0.7913716)
y = c(1.0424226, 0.1754048, -1.4523334, 0.2349112)
z = c(0.000, 3.042, 0.370, 0.122)
EX = seq(from=min(x), to=max(x), length=100)
WHY = seq(from=min(y), to=max(y), length=100)
ZZ = interp(x=x, y=y, z=z, xo=EX, yo=WHY, extrap=FALSE)
plot(x,y, type='n')
image(ZZ, add=TRUE)
points(x,y)
text(x,y,labels=z)
BUG:
Notice the convex hull is wrong.
It includes only 3 of the 4 points provided.
If you add another point near by it does some
really wierd stuff.
x = c(x, -0.3950865)
y = c(y, -1.449117)
z = c(z, .37)
I do not think it should behave in this manner.
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