This section contain functions for input data for most of further samples.
MGL code:
func 'prepare1d' new y 50 3 modify y '0.7*sin(2*pi*x)+0.5*cos(3*pi*x)+0.2*sin(pi*x)' modify y 'sin(2*pi*x)' 1 modify y 'cos(2*pi*x)' 2 new x1 50 'x' new x2 50 '0.05-0.03*cos(pi*x)' new y1 50 '0.5-0.3*cos(pi*x)' new y2 50 '-0.3*sin(pi*x)' return func 'prepare2d' new a 50 40 '0.6*sin(pi*(x+1))*sin(1.5*pi*(y+1))+0.4*cos(0.75*pi*(x+1)*(y+1))' new b 50 40 '0.6*cos(pi*(x+1))*cos(1.5*pi*(y+1))+0.4*cos(0.75*pi*(x+1)*(y+1))' return func 'prepare3d' new c 61 50 40 '-2*(x^2+y^2+z^4-z^2)+0.2' new d 61 50 40 '1-2*tanh((x+y)*(x+y))' return func 'prepare2v' new a 20 30 '0.6*sin(pi*(x+1))*sin(1.5*pi*(y+1))+0.4*cos(0.75*pi*(x+1)*(y+1))' new b 20 30 '0.6*cos(pi*(x+1))*cos(1.5*pi*(y+1))+0.4*cos(0.75*pi*(x+1)*(y+1))' return func 'prepare3v' define $1 pow(x*x+y*y+(z-0.3)*(z-0.3)+0.03,1.5) define $2 pow(x*x+y*y+(z+0.3)*(z+0.3)+0.03,1.5) new ex 10 10 10 '0.2*x/$1-0.2*x/$2' new ey 10 10 10 '0.2*y/$1-0.2*y/$2' new ez 10 10 10 '0.2*(z-0.3)/$1-0.2*(z+0.3)/$2' return
C++ code:
void mgls_prepare1d(mglData *y, mglData *y1, mglData *y2, mglData *x1, mglData *x2)
{
long n=50;
if(y) y->Create(n,3);
if(x1) x1->Create(n);
if(x2) x2->Create(n);
if(y1) y1->Create(n);
if(y2) y2->Create(n);
for(long i=0;i<n;i++)
{
double xx = i/(n-1.);
if(y)
{
y->a[i] = 0.7*sin(2*M_PI*xx) + 0.5*cos(3*M_PI*xx) + 0.2*sin(M_PI*xx);
y->a[i+n] = sin(2*M_PI*xx);
y->a[i+2*n] = cos(2*M_PI*xx);
}
if(y1) y1->a[i] = 0.5+0.3*cos(2*M_PI*xx);
if(y2) y2->a[i] = 0.3*sin(2*M_PI*xx);
if(x1) x1->a[i] = xx*2-1;
if(x2) x2->a[i] = 0.05+0.03*cos(2*M_PI*xx);
}
}
//-----------------------------------------------------------------------------
void mgls_prepare2d(mglData *a, mglData *b, mglData *v)
{
long n=50,m=40;
if(a) a->Create(n,m);
if(b) b->Create(n,m);
if(v) { v->Create(9); v->Fill(-1,1); }
for(long j=0;j<m;j++) for(long i=0;i<n;i++)
{
double x = i/(n-1.), y = j/(m-1.);
long i0 = i+n*j;
if(a) a->a[i0] = 0.6*sin(2*M_PI*x)*sin(3*M_PI*y)+0.4*cos(3*M_PI*x*y);
if(b) b->a[i0] = 0.6*cos(2*M_PI*x)*cos(3*M_PI*y)+0.4*cos(3*M_PI*x*y);
}
}
//-----------------------------------------------------------------------------
void mgls_prepare3d(mglData *a, mglData *b)
{
long n=61,m=50,l=40;
if(a) a->Create(n,m,l);
if(b) b->Create(n,m,l);
for(long k=0;k<l;k++) for(long j=0;j<m;j++) for(long i=0;i<n;i++)
{
double x=2*i/(n-1.)-1, y=2*j/(m-1.)-1, z=2*k/(l-1.)-1;
long i0 = i+n*(j+m*k);
if(a) a->a[i0] = -2*(x*x + y*y + z*z*z*z - z*z - 0.1);
if(b) b->a[i0] = 1-2*tanh((x+y)*(x+y));
}
}
//-----------------------------------------------------------------------------
void mgls_prepare2v(mglData *a, mglData *b)
{
long n=20,m=30;
if(a) a->Create(n,m);
if(b) b->Create(n,m);
for(long j=0;j<m;j++) for(long i=0;i<n;i++)
{
double x=i/(n-1.), y=j/(m-1.);
long i0 = i+n*j;
if(a) a->a[i0] = 0.6*sin(2*M_PI*x)*sin(3*M_PI*y)+0.4*cos(3*M_PI*x*y);
if(b) b->a[i0] = 0.6*cos(2*M_PI*x)*cos(3*M_PI*y)+0.4*cos(3*M_PI*x*y);
}
}
//-----------------------------------------------------------------------------
void mgls_prepare3v(mglData *ex, mglData *ey, mglData *ez)
{
long n=10;
double z0=0.3;
if(!ex || !ey || !ez) return;
ex->Create(n,n,n); ey->Create(n,n,n); ez->Create(n,n,n);
for(long k=0;k<n;k++) for(long j=0;j<n;j++) for(long i=0;i<n;i++)
{
double x=2*i/(n-1.)-1, y=2*j/(n-1.)-1, z=2*k/(n-1.)-1;
long i0 = i+n*(j+k*n);
double r1 = pow(x*x+y*y+(z-z0)*(z-z0)+0.03,1.5);
double r2 = pow(x*x+y*y+(z+z0)*(z+z0)+0.03,1.5);
ex->a[i0]=0.2*x/r1 - 0.2*x/r2;
ey->a[i0]=0.2*y/r1 - 0.2*y/r2;
ez->a[i0]=0.2*(z-z0)/r1 - 0.2*(z+z0)/r2;
}
}
//-----------------------------------------------------------------------------