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| #include "./../../utils/mathematica.h"
double D = 1e-2; // diffusion coef
double s=-1.; // reaction coef \lambda
double exact(double x, double y, double z) { // analytical solution
double kappa = 1./(50.*M_PI);
return exp(-sq((x*y+z*z)/kappa));
}
double src(double x, double y, double z) { // source term for the Poisson Helmholtz equation
double u;
double kappa = 1./(50.*M_PI);
u = (Power(kappa,4)*s + 4*D*Power(x*y + Power(z,2),2)*(Power(x,2) + Power(y,2) + 4*Power(z,2)) - 2*D*Power(kappa,2)*(Power(x + y,2) + 6*Power(z,2)))/(Power(E,Power(x*y + Power(z,2),2)/Power(kappa,2))*Power(kappa,4));
return u;
}
|
