https://github.com/cran/fields
Tip revision: 493a3e14a7a05b0b78de44e0a2b1eec55d9783ac authored by Doug Nychka on 04 September 2009, 00:00:00 UTC
version 6.3
version 6.3
Tip revision: 493a3e1
radbas.f
c**** subroutine to fill in the omega ( or K) matrix for
c**** ridge regression S funcion
c**** K_ij= radfun( distance( x1_i, x2_j))
c
subroutine radbas( nd,x1,n1, x2,n2, par, k)
implicit double precision (a-h,o-z)
integer nd,n1,n2,ic
real*8 par(1),x1(n1,nd), x2(n2,nd), k(n1,n2)
c **** loop through columns of output matrix K
c*** outer most loop over columns of x1 and x2 should reduce paging
do 5 ic= 1, nd
do 10 j =1,n2
xtemp= x2(j,ic)
do 15 i= 1, n1
c
c** accumulate squared differences
c
k(i,j)= (x1(i,ic)- xtemp)**2 + k(i,j)
15 continue
10 continue
5 continue
c**** at this point k( i,j) is the squared distnace between x1_i and x2_j
c*** now evaluate radial basis functions
nbig= n1*n2
c***** Now evalute the radial basis functions with the
c distances. radfun will just loop through the matrix
c as stacked column vectors.
call radfun( nbig,k(1,1),par)
return
end