void splint2_a(double *ya, double *y,
int n1, int n2, int ni1, int ni2)
{
double *x1a, *x2a, *xi1a, *xi2a;
int i;
x1a = new double[n1];
x2a = new double[n2];
xi1a = new double[ni1];
xi2a = new double[ni2];
for(i=0; i<n1; i++) x1a[i] = i*1.0/(n1-1);
for(i=0; i<n2; i++) x2a[i] = i*1.0/(n2-1);
for(i=0; i<ni1; i++) xi1a[i] = i*1.0/(ni1-1);
for(i=0; i<ni2; i++) xi2a[i] = i*1.0/(ni2-1);
splint2(x1a, x2a, ya,
xi1a, xi2a, y,
n1, n2, ni1, ni2);
delete [] x1a;
delete [] x2a;
delete [] xi1a;
delete [] xi2a;
}
/******************************************************************************\
* 3-D spline interpolation
*
* Parameters:
* x1a [in] axis-1 coordinate (chage slowest)
* x2a [in] axis-2 coordinate
* x3a [in] axis-3 coordinate (change fast)
* ya [in] values
* xi1a [in] interpolate axis-1 coordinate
* xi2a [in] interpolate axis-2 coordinate
* xi3a [in] interpolate axis-3 coordinate
* y [out] interpolated values
* n1 [in] data number in axis-1
* n2 [in] data number in axis-2
* n3 [in] data number in axis-3
* ni1 [in] data number in interpolated axis-1
* ni2 [in] data number in interpolated axis-2
* ni3 [in] data number in interpolated axis-3
\******************************************************************************/
void splint3(double *x1a, double *x2a, double *x3a, double *ya,
double *xi1a, double *xi2a, double *xi3a, double *y,
int n1, int n2, int n3, int ni1, int ni2, int ni3)
{
int i, j, k;
double *ytmp, *p1, *p2;
double *pp1, *pp2;
int omp_tn, omp_ti;
#ifdef HAVE_OPENMP
omp_tn = omp_get_max_threads();
#else
omp_tn = 1;
#endif
// allocate buffer
ytmp = new double[n1*ni2*ni3];
p1 = new double[n1*omp_tn];
p2 = new double[ni1*omp_tn];
// interpolation in axis-2 and axis-3
#ifdef HAVE_OPENMP
#pragma omp parallel for private(k)
#endif
for (k=0; k<n1; k++) {
splint2(x2a, x3a, ya+k*n2*n3,
xi2a, xi3a, ytmp+k*ni2*ni3,
n2, n3, ni2, ni3);
}
// interpolation in axis1
#ifdef HAVE_OPENMP
#pragma omp parallel for private(i,j,k,pp1,pp2,omp_ti)
#endif
for (i=0; i<ni3; i++) {
for (j=0; j<ni2; j++) {
#ifdef HAVE_OPENMP
omp_ti = omp_get_thread_num();
#else
omp_ti = 0;
#endif
pp1 = p1 + n1*omp_ti;
pp2 = p2 + ni1*omp_ti;
for (k=0; k<n1; k++)
pp1[k] = ytmp[k*ni2*ni3 + j*ni3 + i];
splint(x1a, pp1, xi1a, pp2, n1, ni1);
for (k=0; k<ni1; k++)
y[k*ni2*ni3 + j*ni3 + i] = pp2[k];
}
}
// free temp buffer
delete [] ytmp;
delete [] p1;
delete [] p2;
}
double gintegrand(double b,int x,int y,double *p2,double *nodes,
double *phi_nodes,int nb_nodes,double scale)
{
double xpos,ypos,tmp,tmp2, phi_b,phip_b, u;
double g_x,g_y,gprime_x,gprime_y;
double integ=0;
/* Spline interpolation of the ridge; computation of its derivative
---------------------------------------------------------------*/
splint2(nodes,phi_nodes,p2,nb_nodes,b,&phi_b,&phip_b);
/* Evaluation of the integrand
--------------------------*/
xpos = (x-b);
g_x = gfunc(xpos,scale);
gprime_x = gprime(xpos,scale);
ypos = (y-b);
g_y = gfunc(ypos,scale);
gprime_y = gprime(ypos,scale);
u = phi_b*(x-y);
/* First part */
tmp= (phip_b*phip_b*xpos*ypos - phi_b*phip_b*(xpos+ypos));
tmp *= g_x*g_y;
integ = tmp;
tmp=gprime_x*gprime_y;
integ += tmp;
integ *= cos(u);
/* Second part */
tmp2 = phip_b*xpos -phi_b;
tmp2 *= (gprime_y*g_x);
tmp = phip_b*ypos -phi_b;
tmp *= (gprime_x*g_y);
tmp2 -= tmp;
tmp2 *= sin(u);
integ += tmp2;
return integ;
}