void SBGaussian::SBGaussianImpl::fillXValue(tmv::MatrixView<double> val,
double x0, double dx, int izero,
double y0, double dy, int jzero) const
{
dbg<<"SBGaussian fillXValue\n";
dbg<<"x = "<<x0<<" + i * "<<dx<<", izero = "<<izero<<std::endl;
dbg<<"y = "<<y0<<" + j * "<<dy<<", jzero = "<<jzero<<std::endl;
if (izero != 0 || jzero != 0) {
xdbg<<"Use Quadrant\n";
fillXValueQuadrant(val,x0,dx,izero,y0,dy,jzero);
} else {
xdbg<<"Non-Quadrant\n";
assert(val.stepi() == 1);
const int m = val.colsize();
const int n = val.rowsize();
typedef tmv::VIt<double,1,tmv::NonConj> It;
x0 *= _inv_sigma;
dx *= _inv_sigma;
y0 *= _inv_sigma;
dy *= _inv_sigma;
// The Gaussian profile is separable:
// val = _norm * exp(-0.5 * (x*x + y*y)
// = _norm * exp(-0.5 * x*x) * exp(-0.5 * y*y)
tmv::Vector<double> gauss_x(m);
It xit = gauss_x.begin();
for (int i=0;i<m;++i,x0+=dx) *xit++ = exp(-0.5 * x0*x0);
tmv::Vector<double> gauss_y(n);
It yit = gauss_y.begin();
for (int j=0;j<n;++j,y0+=dy) *yit++ = exp(-0.5 * y0*y0);
val = _norm * gauss_x ^ gauss_y;
}
}
void SBGaussian::SBGaussianImpl::fillXImage(ImageView<T> im,
double x0, double dx, int izero,
double y0, double dy, int jzero) const
{
dbg<<"SBGaussian fillXImage\n";
dbg<<"x = "<<x0<<" + i * "<<dx<<", izero = "<<izero<<std::endl;
dbg<<"y = "<<y0<<" + j * "<<dy<<", jzero = "<<jzero<<std::endl;
if (izero != 0 || jzero != 0) {
xdbg<<"Use Quadrant\n";
fillXImageQuadrant(im,x0,dx,izero,y0,dy,jzero);
} else {
xdbg<<"Non-Quadrant\n";
const int m = im.getNCol();
const int n = im.getNRow();
T* ptr = im.getData();
const int skip = im.getNSkip();
assert(im.getStep() == 1);
x0 *= _inv_sigma;
dx *= _inv_sigma;
y0 *= _inv_sigma;
dy *= _inv_sigma;
// The Gaussian profile is separable:
// im(x,y) = _norm * exp(-0.5 * (x*x + y*y)
// = _norm * exp(-0.5 * x*x) * exp(-0.5 * y*y)
std::vector<double> gauss_x(m);
std::vector<double> gauss_y(n);
typedef std::vector<double>::iterator It;
It xit = gauss_x.begin();
for (int i=0; i<m; ++i,x0+=dx) *xit++ = fmath::expd(-0.5 * x0*x0);
if ((x0 == y0) && (dx == dy) && (m==n)) {
gauss_y = gauss_x;
} else {
It yit = gauss_y.begin();
for (int j=0; j<n; ++j,y0+=dy) *yit++ = fmath::expd(-0.5 * y0*y0);
}
for (int j=0; j<n; ++j,ptr+=skip) {
for (int i=0; i<m; ++i)
*ptr++ = _norm * gauss_x[i] * gauss_y[j];
}
}
}