23char cfrchebp_C[] =
"$Header: /cvsroot/Lorene/C++/Source/Non_class_members/Coef/FFTW3/cfrchebp.C,v 1.3 2014/10/13 08:53:18 j_novak Exp $" ;
133fftw_plan prepare_fft(
int, Tbl*&) ;
134double* cheb_ini(
const int) ;
138void cfrchebp(
const int* deg,
const int* dimf,
double* ff,
const int* dimc,
158 cout <<
"cfrchebp: nr > n3f : nr = " << nr <<
" , n3f = "
164 cout <<
"cfrchebp: nr > n3c : nr = " << nr <<
" , n3c = "
170 cout <<
"cfrchebp: n1f > n1c : n1f = " << n1f <<
" , n1c = "
176 cout <<
"cfrchebp: n2f > n2c : n2f = " << n2f <<
" , n2c = "
188 fftw_plan p = prepare_fft(nm1, pg) ;
192 double* sinp = cheb_ini(nr);
196 int n2n3f = n2f * n3f ;
197 int n2n3c = n2c * n3c ;
205 int borne_phi = ( n1f > 1 ) ? n1f-1 : 1 ;
207 for (j=0; j< borne_phi; j++) {
211 for (k=0; k<n2f; k++) {
213 int i0 = n2n3f * j + n3f * k ;
214 double* ff0 = ff + i0 ;
216 i0 = n2n3c * j + n3c * k ;
217 double* cf0 = cf + i0 ;
225 double fmoins0 = 0.5 * ( ff0[nm1] - ff0[0] );
229 for ( i = 1; i < nm1s2 ; i++ ) {
235 int ixsym = nm1 - isym ;
238 double fp = 0.5 * ( ff0[ix] + ff0[ixsym] ) ;
240 double fms = 0.5 * ( ff0[ix] - ff0[ixsym] ) * sinp[i] ;
241 g.set(i) = fp + fms ;
242 g.set(isym) = fp - fms ;
245 g.set(0) = 0.5 * ( ff0[nm1] + ff0[0] );
246 g.set(nm1s2) = ff0[nm1s2];
259 double fac = 2./double(nm1) ;
260 cf0[0] = g(0) / double(nm1) ;
261 for (i=2; i<nm1; i += 2) cf0[i] = fac*g(i/2) ;
262 cf0[nm1] = g(nm1s2) / double(nm1) ;
273 for ( i = 3; i < nr; i += 2 ) {
274 cf0[i] = cf0[i-2] + fac * g(nm1-i/2) ;
279 double c1 = ( fmoins0 - som ) / nm1s2 ;
283 for ( i = 3; i < nr; i += 2 ) cf0[i] += c1 ;