Find polynomial roots (`#include
<mrpt/math/poly_roots.h>`)
// global functions int mrpt::math::solve_poly3(double* x, double a, double b, double c); int mrpt::math::solve_poly4(double* x, double a, double b, double c, double d); int mrpt::math::solve_poly5(double* x, double a, double b, double c, double d, double e); int mrpt::math::solve_poly4Bi(double* x, double b, double d); int mrpt::math::solve_poly4De(double* x, double b, double c, double d); int mrpt::math::solve_poly2(double a, double b, double c, double& r1, double& r2);
Global Functions
int mrpt::math::solve_poly3(double* x, double a, double b, double c)
Solves cubic equation x^3 + a*x^2 + b*x + c = 0.
Returns the number of real roots N <=3. The roots are returned in the first entries of x, i.e. x[0] if N=1, x[0] and x[1] if N=2, etc. Based on poly34.h, by Khashin S.I. http://math.ivanovo.ac.ru/dalgebra/Khashin/index.html - khash2 (at) gmail.com
Parameters:
x |
array of size 3 |
int mrpt::math::solve_poly4(double* x, double a, double b, double c, double d)
Solves quartic equation x^4 + a*x^3 + b*x^2 + c*x + d = 0 by Dekart-Euler method.
Returns the number of real roots N <=4:
return 4: 4 real roots x[0], x[1], x[2], x[3], possible multiple roots
return 2: 2 real roots x[0], x[1] and complex x[2]+-i*x[3],
return 0: two pair of complex roots: x[0]+-i*x[1], x[2]+-i*x[3],
The roots are returned in the first entries of x, i.e. x[0] if N=1, x[0] and x[1] if N=2, etc. Based on poly34.h, by Khashin S.I. http://math.ivanovo.ac.ru/dalgebra/Khashin/index.html - khash2 (at) gmail.com
Parameters:
x |
array of size 4 |
int mrpt::math::solve_poly5( double* x, double a, double b, double c, double d, double e )
Solves equation x^5 + a*x^4 + b*x^3 + c*x^2 + d*x + e = 0.
Returns the number of real roots N <=5. The roots are returned in the first entries of x, i.e. x[0] if N=1, x[0] and x[1] if N=2, etc. Based on poly34.h, by Khashin S.I. http://math.ivanovo.ac.ru/dalgebra/Khashin/index.html - khash2 (at) gmail.com
Parameters:
x |
array of size 5 |
int mrpt::math::solve_poly4Bi(double* x, double b, double d)
Solve equation x^4 + b*x^2 + d = 0.
int mrpt::math::solve_poly4De(double* x, double b, double c, double d)
Solve equation x^4 + b*x^2 + c*x + d = 0.
int mrpt::math::solve_poly2( double a, double b, double c, double& r1, double& r2 )
Solves equation a*x^2 + b*x + c = 0.
Returns the number of real roots: either 0 or 2; or 1 if a=0 (in this case the root is in r1). r1, r2 are the roots. (r1<=r2) Based on poly34.h, by Khashin S.I. http://math.ivanovo.ac.ru/dalgebra/Khashin/index.html - khash2 (at) gmail.com