A class to perform some of the functions of a Radial Basis Function Network. More...
#include <mbl_rbf_network.h>
Public Member Functions | |
| mbl_rbf_network () | |
| Dflt ctor. | |
| void | build (const vcl_vector< vnl_vector< double > > &x, double s=-1) |
| Build weights given examples x. | |
| void | build (const vnl_vector< double > *x, int n, double s=-1) |
| Build weights given n examples x[0] to x[n-1]. | |
| bool | sumToOne () const |
| If true, then the returned weights sum to 1.0. | |
| void | setSumToOne (bool flag) |
| Set flag. If false, calcWts returns raw weights. | |
| const vcl_vector< vnl_vector < double > > & | x () const |
| Array of training vectors x, supplied in last build(). | |
| void | calcWts (vnl_vector< double > &w, const vnl_vector< double > &new_x) |
| Compute weights for given new_x. | |
| short | version_no () const |
| Version number for I/O. | |
| vcl_string | is_a () const |
| Name of the class. | |
| bool | is_class (vcl_string const &s) const |
| True if this is (or is derived from) class named s. | |
| void | print_summary (vcl_ostream &os) const |
| Print class to os. | |
| void | b_write (vsl_b_ostream &bfs) const |
| Save class to binary file stream. | |
| void | b_read (vsl_b_istream &bfs) |
| Load class from binary file stream. | |
Private Member Functions | |
| double | distSqr (const vnl_vector< double > &x, const vnl_vector< double > &y) const |
| double | rbf (double r2) const |
| double | rbf (const vnl_vector< double > &x, const vnl_vector< double > &y) |
Private Attributes | |
| vcl_vector< vnl_vector< double > > | x_ |
| vnl_matrix< double > | W_ |
| double | s2_ |
| bool | sum_to_one_ |
| vnl_vector< double > | v_ |
| workspace. | |
A class to perform some of the functions of a Radial Basis Function Network.
This is a special case of a mixture model pdf, where the same (radially symmetric) pdf kernel is used at each node. The nodes are supplied by build(). calcWts(w,x) calculates the probabilities that x belongs to each node. Given a set of n training vectors, x_i (i=0..n-1), a set of internal weights are computed. Given a new vector, x, a vector of weights, w, are computed such that if x = x_i then w(i+1) = 1, w(j !=i+1) = 0 The sum of the weights should always be unity. If x is not equal to any training vector, the vector of weights varies smoothly. This is useful for interpolation purposes. It can also be used to define non-linear transformations between vector spaces. If Y is a matrix of n columns, each corresponding to a vector in a new space which corresponds to one of the original training vectors x_i, then a vector x can be mapped to Yw in the new space. (Note: y-space does not have to have the same dimension as x space). This class is equivalent to the basis of thin-plate spline warping.
I'm not sure if this is exactly an RBF network in the original definition. I'll check one day.
Definition at line 40 of file mbl_rbf_network.h.
| mbl_rbf_network::mbl_rbf_network | ( | ) |
Dflt ctor.
Definition at line 38 of file mbl_rbf_network.cxx.
| void mbl_rbf_network::b_read | ( | vsl_b_istream & | bfs | ) |
Load class from binary file stream.
Definition at line 233 of file mbl_rbf_network.cxx.
| void mbl_rbf_network::b_write | ( | vsl_b_ostream & | bfs | ) | const |
Save class to binary file stream.
Definition at line 215 of file mbl_rbf_network.cxx.
| void mbl_rbf_network::build | ( | const vcl_vector< vnl_vector< double > > & | x, |
| double | s = -1 |
||
| ) |
Build weights given examples x.
s gives the scaling to use in r2 * vcl_log(r2) r2 = distSqr/(s*s) If s<=0 then a suitable s is estimated from the data
Definition at line 46 of file mbl_rbf_network.cxx.
| void mbl_rbf_network::build | ( | const vnl_vector< double > * | x, |
| int | n, | ||
| double | s = -1 |
||
| ) |
Build weights given n examples x[0] to x[n-1].
s gives the scaling to use in r2 * vcl_log(r2) r2 = distSqr/(s*s) If s<=0 then a suitable s is estimated from the data
Definition at line 55 of file mbl_rbf_network.cxx.
| void mbl_rbf_network::calcWts | ( | vnl_vector< double > & | w, |
| const vnl_vector< double > & | new_x | ||
| ) |
Compute weights for given new_x.
If new_x = x()(i) then w(i+1)==1, w(j!=i+1)==0 Otherwise w varies smoothly depending on distance of new_x from x()'s If sumToOne() then elements of w will sum to 1.0 otherwise they will sum to <=1.0, decreasing as new_x moves away from the training examples x().
Definition at line 133 of file mbl_rbf_network.cxx.
| double mbl_rbf_network::distSqr | ( | const vnl_vector< double > & | x, |
| const vnl_vector< double > & | y | ||
| ) | const [private] |
Definition at line 98 of file mbl_rbf_network.cxx.
| vcl_string mbl_rbf_network::is_a | ( | ) | const |
Name of the class.
Definition at line 185 of file mbl_rbf_network.cxx.
| bool mbl_rbf_network::is_class | ( | vcl_string const & | s | ) | const |
True if this is (or is derived from) class named s.
Definition at line 194 of file mbl_rbf_network.cxx.
| void mbl_rbf_network::print_summary | ( | vcl_ostream & | os | ) | const |
Print class to os.
Definition at line 204 of file mbl_rbf_network.cxx.
| double mbl_rbf_network::rbf | ( | double | r2 | ) | const [inline, private] |
Definition at line 52 of file mbl_rbf_network.h.
| double mbl_rbf_network::rbf | ( | const vnl_vector< double > & | x, |
| const vnl_vector< double > & | y | ||
| ) | [inline, private] |
Definition at line 55 of file mbl_rbf_network.h.
| void mbl_rbf_network::setSumToOne | ( | bool | flag | ) |
Set flag. If false, calcWts returns raw weights.
Definition at line 120 of file mbl_rbf_network.cxx.
| bool mbl_rbf_network::sumToOne | ( | ) | const [inline] |
If true, then the returned weights sum to 1.0.
Definition at line 74 of file mbl_rbf_network.h.
| short mbl_rbf_network::version_no | ( | ) | const |
Version number for I/O.
Definition at line 176 of file mbl_rbf_network.cxx.
| const vcl_vector<vnl_vector<double> >& mbl_rbf_network::x | ( | ) | const [inline] |
Array of training vectors x, supplied in last build().
Definition at line 80 of file mbl_rbf_network.h.
double mbl_rbf_network::s2_ [private] |
Definition at line 44 of file mbl_rbf_network.h.
bool mbl_rbf_network::sum_to_one_ [private] |
Definition at line 46 of file mbl_rbf_network.h.
vnl_vector<double> mbl_rbf_network::v_ [private] |
workspace.
Definition at line 49 of file mbl_rbf_network.h.
vnl_matrix<double> mbl_rbf_network::W_ [private] |
Definition at line 43 of file mbl_rbf_network.h.
vcl_vector<vnl_vector<double> > mbl_rbf_network::x_ [private] |
Definition at line 42 of file mbl_rbf_network.h.
1.7.5.1