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#include <2geom/polynomial.h>
#include <vector>
#include <iterator>
#include <2geom/sbasis.h>
#include <2geom/sbasis-poly.h>
#include <2geom/sbasis-to-bezier.h>
#include <2geom/solver.h>
#include <time.h>
using namespace std;
using namespace Geom;
Poly lin_poly(double a, double b) { // ax + b
Poly p;
p.push_back(b);
p.push_back(a);
return p;
}
Linear linear(double ax, double b) {
return Linear(b, ax+b);
}
double uniform() {
return double(rand()) / RAND_MAX;
}
int main() {
Poly a, b, r;
double timer_precision = 0.01;
double units = 1e6; // us
a = Poly::linear(1, -0.3)*Poly::linear(1, -0.25)*Poly::linear(1, -0.2);
std::cout << a <<std::endl;
SBasis B = poly_to_sbasis(a);
std::cout << B << std::endl;
Bezier bez;
sbasis_to_bezier(bez, B);
cout << bez << endl;
//copy(bez.begin(), bez.end(), ostream_iterator<double>(cout, ", "));
cout << endl;
cout << endl;
cout << endl;
std::vector<std::vector<double> > trials;
// evenly spaced roots
for(int N = 2; N <= 5; N++)
{
std::vector<double> r;
for(int i = 0; i < N; i++)
r.push_back(double(i)/(N-1));
trials.push_back(r);
}
// sort of evenish
for(int N = 0; N <= 5; N++)
{
std::vector<double> r;
for(int i = 0; i < N; i++)
r.push_back(double(i+0.5)/(2*N));
trials.push_back(r);
}
// one at 0.1
for(int N = 0; N <= 5; N++)
{
std::vector<double> r;
for(int i = 0; i < N; i++)
r.push_back(i+0.1);
trials.push_back(r);
}
for(int N = 0; N <= 6; N++)
{
std::vector<double> r;
for(int i = 0; i < N; i++)
r.push_back(i*0.8+0.1);
trials.push_back(r);
}
for(int N = 0; N <= 20; N++)
{
std::vector<double> r;
for(int i = 0; i < N/2; i++) {
r.push_back(0.1);
r.push_back(0.9);
}
trials.push_back(r);
}
for(int i = 0; i <= 20; i++)
{
std::vector<double> r;
for(int i = 0; i < 4; i++) {
r.push_back(uniform()*5 - 2.5);
r.push_back(0.9);
}
trials.push_back(r);
}
double ave_left = 0;
cout << "err from exact\n";
for(auto & trial : trials) {
SBasis B = Linear(1.,1);
sort(trial.begin(), trial.end());
for(double j : trial) {
B = B*linear(1, -j);
}
double left_time;
clock_t end_t = clock()+clock_t(timer_precision*CLOCKS_PER_SEC);
unsigned iterations = 0;
while(end_t > clock()) {
roots(B);
iterations++;
}
left_time = timer_precision*units/iterations;
vector<double> rt = roots(B);
double err = 0;
for(double r : rt) {
double best = fabs(r - trial[0]);
for(unsigned j = 1; j < trial.size(); j++) {
if(fabs(r - trial[j]) < best)
best = fabs(r - trial[j]);
}
err += best;
}
if(err > 1e-8){
for(double j : trial) {
cout << j << ", ";
}
cout << endl;
}
cout << " e: " << err << std::endl;
ave_left += left_time;
}
cout << "average time = " << ave_left/trials.size() << std::endl;
for(int i = 10; i >= 0; i--) {
vector<double> rt = roots(Linear(i,-1));
for(double j : rt) {
cout << j << ", ";
}
cout << endl;
}
return 0;
}
/*
Local Variables:
mode:c++
c-file-style:"stroustrup"
c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
indent-tabs-mode:nil
fill-column:99
End:
*/
// vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:fileencoding=utf-8:textwidth=99 :
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