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inverse_exp_newton

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Zeno Rogue 2023-06-10 11:05:13 +02:00
parent 41fda7545e
commit 901521631f
1 changed files with 16 additions and 0 deletions
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16
hyperpoint.cpp
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@ -1650,6 +1650,22 @@ EX hyperpoint inverse_exp(const shiftpoint h, flagtype prec IS(pNORMAL)) {
return v;
}
/** more precise */
EX hyperpoint inverse_exp_newton(hyperpoint h, int iter) {
auto approx = inverse_exp(shiftless(h));
for(int i=0; i<iter; i++) {
transmatrix T;
ld eps = 1e-3;
hyperpoint cur = direct_exp(approx);
println(hlog, approx, " error = ", hdist(cur, h), " iteration ", i, "/", iter);
for(int i=0; i<3; i++)
set_column(T, i, direct_exp(approx + ctangent(i, eps)) - h);
set_column(T, 3, C03);
approx = approx - inverse(T) * (cur - h) * eps;
}
return approx;
}
EX ld geo_dist(const hyperpoint h1, const hyperpoint h2, flagtype prec IS(pNORMAL)) {
if(!nonisotropic) return hdist(h1, h2);
return hypot_d(3, inverse_exp(shiftless(nisot::translate(h1, -1) * h2, prec)));