!-------------------------------------- LICENCE BEGIN ------------------------------------ !Environment Canada - Atmospheric Science and Technology License/Disclaimer, ! version 3; Last Modified: May 7, 2008. !This is free but copyrighted software; you can use/redistribute/modify it under the terms !of the Environment Canada - Atmospheric Science and Technology License/Disclaimer !version 3 or (at your option) any later version that should be found at: !http://collaboration.cmc.ec.gc.ca/science/rpn.comm/license.html ! !This software 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 above mentioned License/Disclaimer for more details. !You should have received a copy of the License/Disclaimer along with this software; !if not, you can write to: EC-RPN COMM Group, 2121 TransCanada, suite 500, Dorval (Quebec), !CANADA, H9P 1J3; or send e-mail to service.rpn@ec.gc.ca !-------------------------------------- LICENCE END -------------------------------------- !subroutine sft8( r, a, inc, jump, lot, n ) 2 C implicit none #include "taglam4d.cdk"
C integer inc, jump, lot, n real*8 r(*), a(*) C integer i, j, k C real*8 zero, half, one, two parameter( zero = 0.0 ) parameter( half = 0.5 ) parameter( one = 1.0 ) parameter( two = 2.0 ) real*8 cnorm, del, angle, cs integer ij ij(i,j) = 1 + ( j - 1 ) * jump + ( i - 1 ) * inc cnorm = sqrt( two/n ) del = acos( - one )/n C C The transform is along the i-th direction C and the indexing is 1+(j-1)*jump+(i-1)*inc C in the input field a C do k=1,n-1 do j=1,lot r( ij(k,j) ) = zero enddo do i=1,n-1 angle = k * i * del cs = cnorm * sin( angle ) do j=1,lot r( ij(k,j) ) = r( ij(k,j) ) + cs * a( ij(i,j) ) enddo enddo enddo return end