interp2pnt {climates} | R Documentation |
This code was includes bicubic interpolation and bilinear interpolation
adapted from Numerical Recipes in C: The are of scientific computing
http://www.nrbook.com/nr3/ (chapter 3... bicubic interpolation) and a
bicubic interpolation from http://www.paulinternet.nl/?page=bicubic in
java code.
Inputs are a list of points to interpolate to from raster
objects of class 'asc' (adehabitat package), 'RasterLayer' (raster package)
or 'SpatialGridDataFrame' (sp package).
interp2pnt(mat, xout, yout, xin = NULL, yin = NULL, type = 2)
mat |
a matrix of data that can be a raster matrix of class 'asc'
(adehabitat package), 'RasterLayer' (raster package) or
'SpatialGridDataFrame' (sp package) |
xout |
a vector of data representing x coordinates of the output grid. Resulting grid must have square cell sizes if mat is of class 'asc', 'RasterLayer' or 'SpatialGridDataFrame'. |
yout |
a vector of data representing x coordinates of the output grid. Resulting grid must have square cell sizes if mat is of class 'asc', 'RasterLayer' or 'SpatialGridDataFrame'. |
xin |
a vector identifying the locations of the columns of the input data matrix. These are automatically populated if mat is of class 'asc', 'RasterLayer' or 'SpatialGridDataFrame'. |
yin |
a vector identifying the locations of the rows of the input data matrix. These are automatically populated if mat is of class 'asc', 'RasterLayer' or 'SpatialGridDataFrame'. |
type |
an integer value representing the type of interpolation method
used. |
A vector of values in the same order and length of the inputs
xout
and yout
.
Jeremy VanDerWal jjvanderwal@gmail.com
## Not run: #create some data tx = seq(0,3,0.1) ty = seq(0,3,0.1) txy = data.frame(x=tx,y=ty) #create a matrix tmat = matrix(runif(16,1,16),nr=4) #do the interpolations txy$bilinear1 = interp2pnt(tmat,tx,ty,type=1) txy$bicubic2 = interp2pnt(tmat,tx,ty,type=2) txy$bicubic3 = interp2pnt(tmat,tx,ty,type=3) #look at the data head(txy) ## End(Not run)