void lubksb(double** a, int n, int* indx, double* b)
Given a matrix a and permutation vector indx returned from ludcmp, this routines solves the set of linear equations a.x = b. On input b holds the right-hand side vector. On output, it holds the solution vector x. a and indx are not modified by this routine and can be left in place for successive colls with different right-hand sides b.
Parameters:
a | Decomposed matrix. |
---|---|
n | Size of a. |
indx | Permutation vector. |
b | Solution vector. |
Returns:
On return, the b contains the solution vector.
Usage:
double** a; int* p; int d; BOOL success; a = dmatrix(0, 3, 0, 3); p = ivector(0, 3); // initialize the a[i][j] elements success = ludcmp(a, 4, p, &d); if(success){ double* b; b = dvector(0, 3); // initialize the b[j] elements lubksb(a, 4, p, b); free_dvector(b, 0); } free_dmatrix(a, 0, 3, 0); free_ivector(p, 0);}
Header:
#include "linalg.hpp"
See Also:
ludcmp