https://github.com/cran/fields
Tip revision: 66561c3c33070df2578182fed373cf04d4a7c1c6 authored by Douglas Nychka on 13 December 2016, 06:57:09 UTC
version 8.7
version 8.7
Tip revision: 66561c3
multW.f
c fields, Tools for spatial data
c Copyright 2015, Institute for Mathematics Applied Geosciences
c University Corporation for Atmospheric Research
c Licensed under the GPL -- www.gpl.org/licenses/gpl.html
subroutine multWendlandG( mx, my, deltaX, deltaY,
* nc, center, coef, h, flag)
integer mx, my, nc, flag
double precision deltaX, deltaY, center(nc,2), coef(nc)
double precision h(mx,my)
c
integer j, k, l, m1, m2, n1, n2
double precision kstar, lstar, d, wendlandFunction
do j = 1, nc
kStar= center(j,1)
lStar= center(j,2)
m1 = max( ceiling(-deltaX + kStar), 1)
m2 = min( floor( deltaX + kStar), mx)
n1 = max( ceiling(-deltaY + lStar), 1)
n2 = min( floor( deltaY + lStar), my)
do l = n1, n2
do k = m1, m2
d = dsqrt( ((k-kStar)/deltaX)**2 + ((l- lStar)/deltaY)**2)
h(k,l) = h(k,l) + wendlandFunction( d)* coef(j)
c h(k,l) = h(k,l) + 2
enddo
enddo
enddo
flag=0
return
end
double precision function wendlandFunction(d)
double precision d
if( d.GE.1) then
wendlandFunction = 0
else
wendlandFunction = ((1-d)**6) * (35*d**2 + 18*d + 3)/3
endif
return
end