Bool_t TZigZag::NearestPoints(Double_t x, TArrayI &I, TArrayD &W) const {
// One-dimensional case. Gives the 2 nearest points from point x in zigzag numbering.
//W are weights for the points, calculated according to the inverse of their distances
//from x
const Double_t un = 1.0;
const Double_t eps = 1.0e-12;
Int_t k;
Double_t xl,xr,x1,x2,dx,dxs2,w0,w1,wt;
I.Set(2);
W.Set(2);
dx = (fXmax-fXmin)/fNx;
dxs2 = dx/2;
xl = dxs2;
xr = dxs2 + (fNx-1)*dx;
if (x<xl) {
I[0] = 0;
I[1] = 1;
x1 = dxs2;
x2 = dxs2 + dx;
}
else {
if (x>xr) {
I[0] = fNx - 1;
I[1] = fNx - 2;
x1 = dxs2 + (fNx-1)*dx;
x2 = x1 - dx;
}
else {
k = Int_t((x-dxs2)/dx);
I[0] = k;
I[1] = k+1;
x1 = dxs2 + k*dx;
x2 = x1 + dx;
}
}
w0 = TMath::Abs(x1-x);
if (w0<eps) w0 = eps;
w0 = un/w0;
w1 = TMath::Abs(x2-x);
if (w1<eps) w1 = eps;
w1 = un/w1;
wt = w0 + w1;
W[0] = w0/wt;
W[1] = w1/wt;
return kTRUE;
}
Bool_t TZigZag::PointsNear(Double_t x, Double_t y, Double_t &yi,
TArrayD &Tn, TArrayD &Yn) const {
// Two-dimensional case. Finds in I,T,X,Y the 4 points of the grid around point (x,y).
//Then finds the 2 closest points along the zigzag in In,Tn,Xn,Yn.
// If point (x,y) not inside [fXmin,fXmax] and [fYmin,fYmax], make a projection
//towards center and stops at point just after entry and gives the 4 points for it.
const Double_t un = 1.0;
const Double_t aeps = 1.0e-6;
TArrayI Ii(4);
TArrayD Ti(4);
TArrayD Xi(4);
TArrayD Yi(4);
Bool_t ok;
Int_t i;
Int_t kx=0;
Int_t ky=0;
Double_t mx,my,eps;
Double_t xc,xl,xr,dx,dxs2;
Double_t yc,yl,yr,dy,dys2;
Double_t xi,xp,yp;
Double_t xle,xre,yle,yre;
Tn.Set(2);
Yn.Set(2);
dx = (fXmax-fXmin)/fNx;
dxs2 = dx/2;
dy = (fYmax-fYmin)/fNy;
dys2 = dy/2;
xl = dxs2;
xr = dxs2 + (fNx-1)*dx;
yl = dys2;
yr = dys2 + (fNy-1)*dy;
if ((yr-yl) > (xr-xl)) eps = aeps*(yr-yl);
else eps = aeps*(xr-xl);
xle = xl + eps;
xre = xr - eps;
yle = yl + eps;
yre = yr - eps;
if ((x>=xle) && (x<=xre) && (y>=yle) && (y<=yre)) {
xi = x;
yi = y;
kx = Int_t((xi-dxs2)/dx) + 1;
ky = Int_t((yi-dys2)/dy) + 1;
ok = kTRUE;
}//end if ((x>xl) && (x<xr) && (y>yl) && (y<yr))
else {
xc = (fXmax-fXmin)/2;
yc = (fYmax-fYmin)/2;
mx = (y-yc)/(x-xc);
my = un/mx;
xi = xle;
yi = yc + mx*(xi-xc);
ok = IsInside(xi,yi,x,y,xc,yc,xl,xr,yl,yr);
if (!ok) {
xi = xre;
yi = yc + mx*(xi-xc);
ok = IsInside(xi,yi,x,y,xc,yc,xl,xr,yl,yr);
if (!ok) {
yi = yle;
xi = xc + my*(yi-yc);
ok = IsInside(xi,yi,x,y,xc,yc,xl,xr,yl,yr);
if (!ok) {
yi = yre;
xi = xc + my*(yi-yc);
ok = IsInside(xi,yi,x,y,xc,yc,xl,xr,yl,yr);
}//end if (!ok)
}//end if (!ok)
}//end if (!ok)
if (ok) {
kx = Int_t((xi-dxs2)/dx) + 1;
ky = Int_t((yi-dys2)/dy) + 1;
}
else {
cout << "TZigZag::PointsNear : ERROR point inside not found" << endl;
}
}//end else if ((x>xl) && (x<xr) && (y>yl) && (y<yr))
if (ok) {
//Point kx,ky
xp = dxs2 + (kx-1)*dx;
yp = dys2 + (ky-1)*dy;
i = NToZZ(kx,ky);
Ii[0] = i;
Ti[0] = T(i);
Xi[0] = xp;
Yi[0] = yp;
//Point kx+1,ky
xp = dxs2 + kx*dx;
yp = dys2 + (ky-1)*dy;
i = NToZZ(kx+1,ky);
Ii[1] = i;
Ti[1] = T(i);
Xi[1] = xp;
Yi[1] = yp;
//Point kx,ky+1
xp = dxs2 + (kx-1)*dx;
yp = dys2 + ky*dy;
i = NToZZ(kx,ky+1);
Ii[2] = i;
Ti[2] = T(i);
Xi[2] = xp;
Yi[2] = yp;
//Point kx+1,ky+1
xp = dxs2 + kx*dx;
yp = dys2 + ky*dy;
i = NToZZ(kx+1,ky+1);
Ii[3] = i;
Ti[3] = T(i);
Xi[3] = xp;
Yi[3] = yp;
//Finding the 2 points along the zigzag
Order(4,Ii,Ti,Xi,Yi);
Yn[0] = Yi[0];
Tn[0] = Ti[0] + ((Ti[1] - Ti[0])/(Xi[1] -Xi[0]))*(xi - Xi[0]);
Yn[1] = Yi[2];
Tn[1] = Ti[2] + ((Ti[3] - Ti[2])/(Xi[3] -Xi[2]))*(xi - Xi[2]);
}
return ok;
}
Bool_t TZigZag::NearestPoints(Double_t x, Double_t y, Double_t z, TArrayI &I, TArrayD &W) const {
// 3-dimensional case. Gives the 8 nearest points from point x in zigzag numbering.
//W are weights for the points, calculated according to the inverse of their distances
//from x. If point (x,y) not inside [fXmin,fXmax],[fYmin,fYmax],[fZmin,fZmax], make a
//projection towards center and stops at point just after entry and gives the 8 points
//for it.
const Double_t un = 1.0;
const Double_t aeps = 1.0e-6;
Bool_t ok;
Int_t i;
Int_t kx=0;
Int_t ky=0;
Int_t kz=0;
Double_t mx,my,mz,eps;
Double_t xc,xl,xr,dx,dxs2;
Double_t yc,yl,yr,dy,dys2;
Double_t zc,zl,zr,dz,dzs2;
Double_t xi,yi,zi,ti,xp,yp,zp;
Double_t xle,xre,yle,yre,zle,zre;
Double_t w0,w1,w2,w3,w4,w5,w6,w7,wt;
I.Set(8);
W.Set(8);
for (i=0;i<8;i++) {
I[i] = -1;
W[i] = -un;
}
dx = (fXmax-fXmin)/fNx;
dxs2 = dx/2;
dy = (fYmax-fYmin)/fNy;
dys2 = dy/2;
dz = (fZmax-fZmin)/fNy;
dzs2 = dz/2;
xl = dxs2;
xr = dxs2 + (fNx-1)*dx;
yl = dys2;
yr = dys2 + (fNy-1)*dy;
zl = dzs2;
zr = dzs2 + (fNz-1)*dz;
w0 = xr - xl;
w1 = yr - yl;
w2 = zr - zl;
w0 = TMath::Max(w0,w1);
w0 = TMath::Max(w0,w2);
eps = aeps*w0;
if ((x>=xl) && (x<=xr) && (y>=yl) && (y<=yr) && (z>=zl) && (z<=zr)) {
xi = x;
yi = y;
zi = z;
kx = Int_t((xi-dxs2)/dx) + 1;
ky = Int_t((yi-dys2)/dy) + 1;
kz = Int_t((zi-dzs2)/dz) + 1;
ok = kTRUE;
}//end if ((x>xl) && (x<xr) && (y>yl) && (y<yr) && (z>zl) && (z<zr))
else {
xc = (fXmax-fXmin)/2;
yc = (fYmax-fYmin)/2;
zc = (fZmax-fZmin)/2;
xle = xl + eps;
xre = xr - eps;
yle = yl + eps;
yre = yr - eps;
zle = zl + eps;
zre = zr - eps;
mx = x - xc;
my = y - yc;
mz = z - zc;
//intercept with xle
xi = xle;
ti = (xi-xc)/mx;
yi = yc + my*ti;
zi = zc + mz*ti;
ok = IsInside(xi,yi,zi,x,y,z,xc,yc,zc,xl,xr,yl,yr,zl,zr);
if (!ok) {
//intercept with xre
xi = xre;
ti = (xi-xc)/mx;
yi = yc + my*ti;
zi = zc + mz*ti;
ok = IsInside(xi,yi,zi,x,y,z,xc,yc,zc,xl,xr,yl,yr,zl,zr);
if (!ok) {
//intercept with yle
yi = yle;
ti = (yi-yc)/my;
xi = xc + mx*ti;
zi = zc + mz*ti;
ok = IsInside(xi,yi,zi,x,y,z,xc,yc,zc,xl,xr,yl,yr,zl,zr);
if (!ok) {
//intercept with yre
yi = yre;
ti = (yi-yc)/my;
xi = xc + mx*ti;
zi = zc + mz*ti;
ok = IsInside(xi,yi,zi,x,y,z,xc,yc,zc,xl,xr,yl,yr,zl,zr);
if (!ok) {
//intercept with zle
zi = zle;
ti = (zi-zc)/mz;
xi = xc + mx*ti;
yi = yc + my*ti;
ok = IsInside(xi,yi,zi,x,y,z,xc,yc,zc,xl,xr,yl,yr,zl,zr);
if (!ok) {
//intercept with zre
zi = zre;
ti = (zi-zc)/mz;
xi = xc + mx*ti;
yi = yc + my*ti;
ok = IsInside(xi,yi,zi,x,y,z,xc,yc,zc,xl,xr,yl,yr,zl,zr);
}//end if (!ok) intercept with zre
}//end if (!ok) intercept with zle
}//end if (!ok) intercept with yre
}//end if (!ok) intercept with yle
}//end if (!ok) intercept with xre
if (ok) {
kx = Int_t((xi-dxs2)/dx) + 1;
ky = Int_t((yi-dys2)/dy) + 1;
kz = Int_t((zi-dzs2)/dz) + 1;
}
else {
cout << "TZigZag::NearestPoints : ERROR point inside not found" << endl;
}
}//end else if ((x>xl) && (x<xr) && (y>yl) && (y<yr) && (z>zl) && (z<zr))
if (ok) {
Double_t fx,fy,fz;
//Point kx,ky,kz
xp = dxs2 + (kx-1)*dx;
yp = dys2 + (ky-1)*dy;
zp = dzs2 + (kz-1)*dz;
fx = x - xp;
fy = y - yp;
fz = z - zp;
i = NToZZ(kx,ky,kz);
I[0] = i;
w0 = TMath::Sqrt(fx*fx + fy*fy + fz*fz) + eps;
w0 = un/w0;
//Point kx+1,ky,kz
xp = dxs2 + kx*dx;
yp = dys2 + (ky-1)*dy;
zp = dzs2 + (kz-1)*dz;
fx = x - xp;
fy = y - yp;
fz = z - zp;
i = NToZZ(kx+1,ky,kz);
I[1] = i;
w1 = TMath::Sqrt(fx*fx + fy*fy + fz*fz) + eps;
w1 = un/w1;
//Point kx,ky+1,kz
xp = dxs2 + (kx-1)*dx;
yp = dys2 + ky*dy;
zp = dzs2 + (kz-1)*dz;
fx = x - xp;
fy = y - yp;
fz = z - zp;
i = NToZZ(kx,ky+1,kz);
I[2] = i;
w2 = TMath::Sqrt(fx*fx + fy*fy + fz*fz) + eps;
w2 = un/w2;
//Point kx+1,ky+1,kz
xp = dxs2 + kx*dx;
yp = dys2 + ky*dy;
zp = dzs2 + (kz-1)*dz;
fx = x - xp;
fy = y - yp;
fz = z - zp;
i = NToZZ(kx+1,ky+1,kz);
I[3] = i;
w3 = TMath::Sqrt(fx*fx + fy*fy + fz*fz) + eps;
w3 = un/w3;
//Point kx,ky,kz+1
xp = dxs2 + (kx-1)*dx;
yp = dys2 + (ky-1)*dy;
zp = dzs2 + kz*dz;
fx = x - xp;
fy = y - yp;
fz = z - zp;
i = NToZZ(kx,ky,kz+1);
I[4] = i;
w4 = TMath::Sqrt(fx*fx + fy*fy + fz*fz) + eps;
w4 = un/w4;
//Point kx+1,ky,kz+1
xp = dxs2 + kx*dx;
yp = dys2 + (ky-1)*dy;
zp = dzs2 + kz*dz;
fx = x - xp;
fy = y - yp;
fz = z - zp;
i = NToZZ(kx+1,ky,kz+1);
I[5] = i;
w5 = TMath::Sqrt(fx*fx + fy*fy + fz*fz) + eps;
w5 = un/w5;
//Point kx,ky+1,kz+1
xp = dxs2 + (kx-1)*dx;
yp = dys2 + ky*dy;
zp = dzs2 + kz*dz;
fx = x - xp;
fy = y - yp;
fz = z - zp;
i = NToZZ(kx,ky+1,kz+1);
I[6] = i;
w6 = TMath::Sqrt(fx*fx + fy*fy + fz*fz) + eps;
w6 = un/w6;
//Point kx+1,ky+1,kz+1
xp = dxs2 + kx*dx;
yp = dys2 + ky*dy;
zp = dzs2 + kz*dz;
fx = x - xp;
fy = y - yp;
fz = z - zp;
i = NToZZ(kx+1,ky+1,kz+1);
I[7] = i;
w7 = TMath::Sqrt(fx*fx + fy*fy + fz*fz) + eps;
w7 = un/w7;
//
wt = w0 + w1 + w2 + w3 + w4 + w5 + w6 + w7;
W[0] = w0/wt;
W[1] = w1/wt;
W[2] = w2/wt;
W[3] = w3/wt;
W[4] = w4/wt;
W[5] = w5/wt;
W[6] = w6/wt;
W[7] = w7/wt;
}
return ok;
}
