Cross Reference: /inkscape/src/2geom/sbasis-roots.cpp

Lines Matching defs:roots
36  * It is more efficient to find roots of f(t) = c_0, c_1, ... all at once, rather than iterating.
39  *  multi-roots using bernstein method, one approach would be:
41     take median and find roots of that
47  *  the gsl poly roots finder is faster than bernstein too, but we don't use it for 3 reasons:
53  c) it finds all roots, even complex ones.  We don't want to accidently treat a nearly real root as a real root
55 From memory gsl poly roots was about 10 times faster than bernstein in the case where all the roots
96     vector<double>extrema = roots(df);
106     vector<double>extrema = roots(df);
196          From this we conclude there are no roots before a'=a+min((f(a)-c)/m,(C-f(a))/M).
197          Do the same for b: compute some b' such that there are no roots in (b',b].
199   unfortunately, extra care is needed about rounding errors, and also to avoid the repetition of roots,
202 //TODO: Make sure the code is "rounding-errors proof" and take care about repetition of roots!
217 				 std::vector<std::vector<double> > &roots,
229             roots[idx].push_back(a);
230             roots[idx].push_back(b);
240 //                 roots[a]=idxa;
241 //                 roots[b]=idxa;
250 //             if(a<t&&t<b) roots[t]=i;
261             roots[idx].push_back((a+b)/2);
278         roots[idxa].push_back(a);
288         roots[idxb].push_back(b);
304         multi_roots_internal(f,df,levels,roots,htol,vtol,t0,f(t0),t1,f(t1));
311             roots[idx].push_back(t);
318         multi_roots_internal(f,df,levels,roots,htol,vtol,t0     ,f(t0)   ,t_left,ft_left);
319         multi_roots_internal(f,df,levels,roots,htol,vtol,t_right,ft_right,t1    ,f(t1)  );
328     \returns a vector of vectors, one for each y giving roots
331 results = roots(f(y_i)) for all y_i
338          From this we conclude there are no roots before a'=a+min((f(a)-c)/m,(C-f(a))/M).
339          Do the same for b: compute some b' such that there are no roots in (b',b].
341   unfortunately, extra care is needed about rounding errors, and also to avoid the repetition of roots,
344 TODO: Make sure the code is "rounding-errors proof" and take care about repetition of roots!
353     std::vector<std::vector<double> > roots(levels.size(), std::vector<double>());
356     multi_roots_internal(f,df,levels,roots,htol,vtol,a,f(a),b,f(b));
358     return(roots);
403   unfortunately, extra care is needed about rounding errors, and also to avoid the repetition of roots,
569                    std::vector<double> & roots,
573         return; // no roots here
576         roots.push_back(left*(1-t) + t*right);
580     subdiv_sbasis(compose(s, Linear(0, 0.5)), roots, left, middle);
581     subdiv_sbasis(compose(s, Linear(0.5, 1.)), roots, middle, right);
610  \see Bezier::roots
611  \returns vector of zeros (roots)
614 std::vector<double> roots(SBasis const & s) {
625             return bz.roots();
629 std::vector<double> roots(SBasis const & s, Interval const ivl) {
640             return bz.roots(ivl);