Update polynomial coefficients with track data. 
  124     double var_bd = var_d0 + var_b;
 
  127     coeff[g_size*g_size2] += z_0;
 
  128     coeff[g_size*g_size2+1] += z_0*z_0;
 
  131     coeff[g_size*g_size2+2] += 1;
 
  138     coeff[
idx(0, 0, 0, 0, 0, 0)] += -
pow(d_0, 2)/(2*var_bd);
 
  144     coeff[
idx(0, 0, 0, 1, 0, 0)] += cos_phi*d_0*z_0/var_bd;
 
  145     coeff[
idx(0, 0, 0, 1, 0, 1)] += -
pow(cos_phi, 3)*d_0*z_0/
pow(var_bd, 2);
 
  146     coeff[
idx(0, 0, 0, 1, 0, 2)] += 
pow(cos_phi, 5)*d_0*z_0/
pow(var_bd, 3);
 
  147     coeff[
idx(0, 0, 0, 1, 1, 0)] += -cos_phi*d_0*
pow(sin_phi, 2)*z_0/
pow(var_bd, 2);
 
  148     coeff[
idx(0, 0, 0, 1, 1, 1)] += 2*
pow(cos_phi, 3)*d_0*
pow(sin_phi, 2)*z_0/
pow(var_bd, 3);
 
  149     coeff[
idx(0, 0, 0, 1, 2, 0)] += cos_phi*d_0*
pow(sin_phi, 4)*z_0/
pow(var_bd, 3);
 
  150     coeff[
idx(0, 0, 0, 2, 0, 0)] += -
pow(cos_phi, 2)*
pow(z_0, 2)/(2*var_bd);
 
  155     coeff[
idx(0, 0, 0, 2, 2, 0)] += -
pow(cos_phi, 2)*
pow(sin_phi, 4)*
pow(z_0, 2)/(2*
pow(var_bd, 3));
 
  156     coeff[
idx(0, 0, 1, 0, 0, 0)] += -d_0*sin_phi*z_0/var_bd;
 
  157     coeff[
idx(0, 0, 1, 0, 0, 1)] += 
pow(cos_phi, 2)*d_0*sin_phi*z_0/
pow(var_bd, 2);
 
  158     coeff[
idx(0, 0, 1, 0, 0, 2)] += -
pow(cos_phi, 4)*d_0*sin_phi*z_0/
pow(var_bd, 3);
 
  159     coeff[
idx(0, 0, 1, 0, 1, 0)] += d_0*
pow(sin_phi, 3)*z_0/
pow(var_bd, 2);
 
  160     coeff[
idx(0, 0, 1, 0, 1, 1)] += -2*
pow(cos_phi, 2)*d_0*
pow(sin_phi, 3)*z_0/
pow(var_bd, 3);
 
  161     coeff[
idx(0, 0, 1, 0, 2, 0)] += -d_0*
pow(sin_phi, 5)*z_0/
pow(var_bd, 3);
 
  162     coeff[
idx(0, 0, 1, 1, 0, 0)] += cos_phi*sin_phi*
pow(z_0, 2)/var_bd;
 
  163     coeff[
idx(0, 0, 1, 1, 0, 1)] += -
pow(cos_phi, 3)*sin_phi*
pow(z_0, 2)/
pow(var_bd, 2);
 
  164     coeff[
idx(0, 0, 1, 1, 0, 2)] += 
pow(cos_phi, 5)*sin_phi*
pow(z_0, 2)/
pow(var_bd, 3);
 
  165     coeff[
idx(0, 0, 1, 1, 1, 0)] += -cos_phi*
pow(sin_phi, 3)*
pow(z_0, 2)/
pow(var_bd, 2);
 
  167     coeff[
idx(0, 0, 1, 1, 2, 0)] += cos_phi*
pow(sin_phi, 5)*
pow(z_0, 2)/
pow(var_bd, 3);
 
  168     coeff[
idx(0, 0, 2, 0, 0, 0)] += -
pow(sin_phi, 2)*
pow(z_0, 2)/(2*var_bd);
 
  170     coeff[
idx(0, 0, 2, 0, 0, 2)] += -
pow(cos_phi, 4)*
pow(sin_phi, 2)*
pow(z_0, 2)/(2*
pow(var_bd, 3));
 
  174     coeff[
idx(0, 1, 0, 0, 0, 0)] += cos_phi*d_0/var_bd;
 
  175     coeff[
idx(0, 1, 0, 0, 0, 1)] += -
pow(cos_phi, 3)*d_0/
pow(var_bd, 2);
 
  176     coeff[
idx(0, 1, 0, 0, 0, 2)] += 
pow(cos_phi, 5)*d_0/
pow(var_bd, 3);
 
  177     coeff[
idx(0, 1, 0, 0, 1, 0)] += -cos_phi*d_0*
pow(sin_phi, 2)/
pow(var_bd, 2);
 
  178     coeff[
idx(0, 1, 0, 0, 1, 1)] += 2*
pow(cos_phi, 3)*d_0*
pow(sin_phi, 2)/
pow(var_bd, 3);
 
  179     coeff[
idx(0, 1, 0, 0, 2, 0)] += cos_phi*d_0*
pow(sin_phi, 4)/
pow(var_bd, 3);
 
  180     coeff[
idx(0, 1, 0, 1, 0, 0)] += -
pow(cos_phi, 2)*z_0/var_bd;
 
  181     coeff[
idx(0, 1, 0, 1, 0, 1)] += 
pow(cos_phi, 4)*z_0/
pow(var_bd, 2);
 
  182     coeff[
idx(0, 1, 0, 1, 0, 2)] += -
pow(cos_phi, 6)*z_0/
pow(var_bd, 3);
 
  183     coeff[
idx(0, 1, 0, 1, 1, 0)] += 
pow(cos_phi, 2)*
pow(sin_phi, 2)*z_0/
pow(var_bd, 2);
 
  184     coeff[
idx(0, 1, 0, 1, 1, 1)] += -2*
pow(cos_phi, 4)*
pow(sin_phi, 2)*z_0/
pow(var_bd, 3);
 
  185     coeff[
idx(0, 1, 0, 1, 2, 0)] += -
pow(cos_phi, 2)*
pow(sin_phi, 4)*z_0/
pow(var_bd, 3);
 
  186     coeff[
idx(0, 1, 1, 0, 0, 0)] += cos_phi*sin_phi*z_0/var_bd;
 
  187     coeff[
idx(0, 1, 1, 0, 0, 1)] += -
pow(cos_phi, 3)*sin_phi*z_0/
pow(var_bd, 2);
 
  188     coeff[
idx(0, 1, 1, 0, 0, 2)] += 
pow(cos_phi, 5)*sin_phi*z_0/
pow(var_bd, 3);
 
  189     coeff[
idx(0, 1, 1, 0, 1, 0)] += -cos_phi*
pow(sin_phi, 3)*z_0/
pow(var_bd, 2);
 
  190     coeff[
idx(0, 1, 1, 0, 1, 1)] += 2*
pow(cos_phi, 3)*
pow(sin_phi, 3)*z_0/
pow(var_bd, 3);
 
  191     coeff[
idx(0, 1, 1, 0, 2, 0)] += cos_phi*
pow(sin_phi, 5)*z_0/
pow(var_bd, 3);
 
  192     coeff[
idx(0, 2, 0, 0, 0, 0)] += -
pow(cos_phi, 2)/(2*var_bd);
 
  193     coeff[
idx(0, 2, 0, 0, 0, 1)] += 
pow(cos_phi, 4)/(2*
pow(var_bd, 2));
 
  194     coeff[
idx(0, 2, 0, 0, 0, 2)] += -
pow(cos_phi, 6)/(2*
pow(var_bd, 3));
 
  195     coeff[
idx(0, 2, 0, 0, 1, 0)] += 
pow(cos_phi, 2)*
pow(sin_phi, 2)/(2*
pow(var_bd, 2));
 
  197     coeff[
idx(0, 2, 0, 0, 2, 0)] += -
pow(cos_phi, 2)*
pow(sin_phi, 4)/(2*
pow(var_bd, 3));
 
  198     coeff[
idx(1, 0, 0, 0, 0, 0)] += -d_0*sin_phi/var_bd;
 
  199     coeff[
idx(1, 0, 0, 0, 0, 1)] += 
pow(cos_phi, 2)*d_0*sin_phi/
pow(var_bd, 2);
 
  200     coeff[
idx(1, 0, 0, 0, 0, 2)] += -
pow(cos_phi, 4)*d_0*sin_phi/
pow(var_bd, 3);
 
  201     coeff[
idx(1, 0, 0, 0, 1, 0)] += d_0*
pow(sin_phi, 3)/
pow(var_bd, 2);
 
  202     coeff[
idx(1, 0, 0, 0, 1, 1)] += -2*
pow(cos_phi, 2)*d_0*
pow(sin_phi, 3)/
pow(var_bd, 3);
 
  203     coeff[
idx(1, 0, 0, 0, 2, 0)] += -d_0*
pow(sin_phi, 5)/
pow(var_bd, 3);
 
  204     coeff[
idx(1, 0, 0, 1, 0, 0)] += cos_phi*sin_phi*z_0/var_bd;
 
  205     coeff[
idx(1, 0, 0, 1, 0, 1)] += -
pow(cos_phi, 3)*sin_phi*z_0/
pow(var_bd, 2);
 
  206     coeff[
idx(1, 0, 0, 1, 0, 2)] += 
pow(cos_phi, 5)*sin_phi*z_0/
pow(var_bd, 3);
 
  207     coeff[
idx(1, 0, 0, 1, 1, 0)] += -cos_phi*
pow(sin_phi, 3)*z_0/
pow(var_bd, 2);
 
  208     coeff[
idx(1, 0, 0, 1, 1, 1)] += 2*
pow(cos_phi, 3)*
pow(sin_phi, 3)*z_0/
pow(var_bd, 3);
 
  209     coeff[
idx(1, 0, 0, 1, 2, 0)] += cos_phi*
pow(sin_phi, 5)*z_0/
pow(var_bd, 3);
 
  210     coeff[
idx(1, 0, 1, 0, 0, 0)] += -
pow(sin_phi, 2)*z_0/var_bd;
 
  211     coeff[
idx(1, 0, 1, 0, 0, 1)] += 
pow(cos_phi, 2)*
pow(sin_phi, 2)*z_0/
pow(var_bd, 2);
 
  212     coeff[
idx(1, 0, 1, 0, 0, 2)] += -
pow(cos_phi, 4)*
pow(sin_phi, 2)*z_0/
pow(var_bd, 3);
 
  213     coeff[
idx(1, 0, 1, 0, 1, 0)] += 
pow(sin_phi, 4)*z_0/
pow(var_bd, 2);
 
  214     coeff[
idx(1, 0, 1, 0, 1, 1)] += -2*
pow(cos_phi, 2)*
pow(sin_phi, 4)*z_0/
pow(var_bd, 3);
 
  215     coeff[
idx(1, 0, 1, 0, 2, 0)] += -
pow(sin_phi, 6)*z_0/
pow(var_bd, 3);
 
  216     coeff[
idx(1, 1, 0, 0, 0, 0)] += cos_phi*sin_phi/var_bd;
 
  217     coeff[
idx(1, 1, 0, 0, 0, 1)] += -
pow(cos_phi, 3)*sin_phi/
pow(var_bd, 2);
 
  218     coeff[
idx(1, 1, 0, 0, 0, 2)] += 
pow(cos_phi, 5)*sin_phi/
pow(var_bd, 3);
 
  219     coeff[
idx(1, 1, 0, 0, 1, 0)] += -cos_phi*
pow(sin_phi, 3)/
pow(var_bd, 2);
 
  220     coeff[
idx(1, 1, 0, 0, 1, 1)] += 2*
pow(cos_phi, 3)*
pow(sin_phi, 3)/
pow(var_bd, 3);
 
  221     coeff[
idx(1, 1, 0, 0, 2, 0)] += cos_phi*
pow(sin_phi, 5)/
pow(var_bd, 3);
 
  222     coeff[
idx(2, 0, 0, 0, 0, 0)] += -
pow(sin_phi, 2)/(2*var_bd);
 
  223     coeff[
idx(2, 0, 0, 0, 0, 1)] += 
pow(cos_phi, 2)*
pow(sin_phi, 2)/(2*
pow(var_bd, 2));
 
  224     coeff[
idx(2, 0, 0, 0, 0, 2)] += -
pow(cos_phi, 4)*
pow(sin_phi, 2)/(2*
pow(var_bd, 3));
 
  225     coeff[
idx(2, 0, 0, 0, 1, 0)] += 
pow(sin_phi, 4)/(2*
pow(var_bd, 2));
 
  227     coeff[
idx(2, 0, 0, 0, 2, 0)] += -
pow(sin_phi, 6)/(2*
pow(var_bd, 3));
 
  229     coeff[
idx(0, 0, 0, 0, 0, 1)+90] += -
pow(cos_phi, 2)/(2*var_bd);
 
  230     coeff[
idx(0, 0, 0, 0, 0, 2)+90] += 
pow(cos_phi, 4)/(4*
pow(var_bd, 2));
 
  231     coeff[
idx(0, 0, 0, 0, 1, 0)+90] += -
pow(sin_phi, 2)/(2*var_bd);
 
  232     coeff[
idx(0, 0, 0, 0, 1, 1)+90] += 
pow(cos_phi, 2)*
pow(sin_phi, 2)/(2*
pow(var_bd, 2));
 
  233     coeff[
idx(0, 0, 0, 0, 2, 0)+90] += 
pow(sin_phi, 4)/(4*
pow(var_bd, 2));