10 #ifndef mrpt_robust_kernels_H
11 #define mrpt_robust_kernels_H
32 template <TRobustKernelType KERNEL_TYPE,
typename T=
double>
struct RobustKernel;
41 inline T
eval(
const T r2, T & out_1st_deriv, T & out_2nd_deriv)
43 out_1st_deriv = 1; out_2nd_deriv = 0;
55 inline T
eval(
const T r2, T & out_1st_deriv, T & out_2nd_deriv)
57 const T param_sq_inv = 1.0/param_sq;
58 const T a = 1+r2*param_sq_inv;
59 const T b = std::sqrt(a);
61 out_2nd_deriv = -0.5*param_sq_inv*out_1st_deriv/a;
62 return 2*param_sq*(b-1);;