SINFONI Pipeline Reference Manual  2.6.0
Functions
1D-Polynomial roots

Functions

cpl_error_code irplib_polynomial_solve_1d_all (const cpl_polynomial *self, cpl_vector *roots, cpl_size *preal)
 Compute all n roots of p(x) = 0, where p(x) is of degree n, n > 0. More...
 

Detailed Description

Function Documentation

cpl_error_code irplib_polynomial_solve_1d_all ( const cpl_polynomial *  self,
cpl_vector *  roots,
cpl_size *  preal 
)

Compute all n roots of p(x) = 0, where p(x) is of degree n, n > 0.

Parameters
selfThe 1D-polynomial
rootsA pre-allocated vector of length n to hold the roots
prealThe number of real roots found, or undefined on error
Returns
CPL_ERROR_NONE or the relevant CPL error code

The *preal real roots are stored first in ascending order, then follows for each pair of complex conjugate roots, the real and imaginary parts of the root in the positive imaginary half-plane, for example for a 3rd degree polynomial with 1 real root, the roots are represented as: x0 = v0 x1 = v1 + i v2 x2 = v1 - i v2, where v0, v1, v2 are the elements of the roots vector.

Possible CPL error code set in this function:

  • CPL_ERROR_NULL_INPUT if an input pointer is NULL
  • CPL_ERROR_INVALID_TYPE if the polynomial has the wrong dimension
  • CPL_ERROR_DATA_NOT_FOUND if the polynomial does not have a degree of at least 1.
  • CPL_ERROR_INCOMPATIBLE_INPUT if the roots vector does not have length n
  • CPL_ERROR_DIVISION_BY_ZERO if a division by zero occurs (n > 4)
  • CPL_ERROR_CONTINUE if the algorithm does not converge (n > 4)

Definition at line 142 of file irplib_polynomial.c.