tests/Wend.test.R

In fields: Tools for Spatial Data

#
# fields  is a package for analysis of spatial data written for
# the R software environment.
# Copyright (C) 2022 Colorado School of Mines
# 1500 Illinois St., Golden, CO 80401
# Contact: Douglas Nychka,  douglasnychka@gmail.edu,
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with the R software environment if not, write to the Free Software
# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
# or see http://www.r-project.org/Licenses/GPL-2
##END HEADER
##END HEADER


# test of Wendland covariance and  stationary.taper.cov

suppressMessages(library(fields))
options( echo=FALSE)
 test.for.zero.flag<- 1

set.seed(123)
x1<- matrix( runif(2*20), ncol=2)
x2<- matrix( runif(2*10), ncol=2)

fields.rdist.near( x1,x2, delta=.75)-> look

temp<- matrix( NA, nrow(x1),nrow(x2))
temp[ look$ind] <- look$ra

temp2<- rdist( x1, x2)
temp2[ temp2> .75] <- NA
#set.panel( 2,1) ; image.plot( temp); image.plot( temp2)

temp[ is.na( temp)]<- 0
temp2[ is.na( temp2)]<- 0
test.for.zero( temp, temp2)


# test of constructing covariance matrix
# and also versions of Wendland function
# default taper is wendland k=2.
DD<- rdist( x1,x2)
temp<- Wendland2.2(DD, aRange=.8)
temp2<- Wendland( DD, aRange=.8, k=2, dimension=2)

test.for.zero( temp, temp2)




stationary.taper.cov( x1,x2, Taper="Wendland2.2", 
           Taper.args= list( aRange=.8), spam.format=FALSE )-> look
temp0<- look

stationary.taper.cov( x1,x2, Taper="Wendland2.2",
           Taper.args= list( aRange=.8), spam.format=TRUE )-> look
temp1<-  spam2full( look)

test.for.zero( temp1, temp0)

stationary.taper.cov( x1,x2, Taper="Wendland",
           Taper.args= list( aRange=.8, k=2, dimension=2),
                     spam.format=TRUE )-> look
temp1b<-  spam2full( look)

temp2<-  Wendland2.2(DD, aRange=.8) * Exponential(DD)
temp3<-  wendland.cov(x1,x2, k=2, aRange=.8) * Exponential(DD)
temp4<-  Wendland(DD, k=2, dimension=2, aRange=.8)* Exponential(DD)


test.for.zero( temp1, temp0, rel=FALSE)
test.for.zero( temp1b, temp0, rel=FALSE)
test.for.zero( temp2, temp0, rel=FALSE)

test.for.zero( temp2, temp3,rel=FALSE)
test.for.zero( temp2, temp4,rel=FALSE)

set.seed( 256)
rv<- runif( nrow(x2))

# test of multiply 
stationary.taper.cov( x1, x2,  C= rv)-> look
temp2<-stationary.taper.cov( x1,x2)

(as.matrix(temp2))%*%(rv)-> look2
test.for.zero( look, look2)

temp2%*%(rv)-> look2
test.for.zero( look, look2)


cat( "Done with testing Wendland family", fill=TRUE)
options( echo=TRUE)