_test_eigen_spline.cxx File Reference

#include <vector>
#include <iostream>
#include <Eigen/Core>
#include <unsupported/Eigen/Splines>

Go to the source code of this file.

Functions
double	uvalue (double x, double low, double high)
VectorXd	uvalues (VectorXd xvals)
int	main (int argc, char *argv[])

Function Documentation

int main	(	int	argc,
		char *	argv[]
	)

Definition at line 27 of file _test_eigen_spline.cxx.

{
    typedef Spline<double,1> Spline2d;

    const VectorXd xvals = (VectorXd(5) << 1,2,3,4,6).finished();
    const VectorXd yvals = xvals.array().square();
    const Spline2d spline = SplineFitting<Spline2d>::Interpolate(yvals.transpose(), 3, uvalues(xvals).transpose());

    const double step = 0.1;
    for (double x = 1; x < 6 + 0.5*step; x += step)
        {
            const double uv = uvalue(x, xvals.minCoeff(), xvals.maxCoeff());
            std::cout << "(" << x << "," << spline(uv).transpose() << "," << spline.derivatives<1>(uv) << ")\n";
        }
    std::cout << std::endl;
}

double uvalue	(	double	x,
		double	low,
		double	high
	)

Definition at line 11 of file _test_eigen_spline.cxx.

{
    return (x - low)/(high-low);
}

VectorXd uvalues

(

VectorXd

xvals

)

Definition at line 16 of file _test_eigen_spline.cxx.

{
    const double low = xvals.minCoeff();
    const double high = xvals.maxCoeff();
    for (int i=0; i<xvals.size(); ++i)
        {
            xvals(i) = uvalue(xvals(i), low, high);
        }
    return xvals;
}