Preprocessor LogPlusOne does what the name says, it adds one to a dense real valued vector and takes the logarithm of each component of it.
![\[ {\bf x}\leftarrow \log({\bf x}+{\bf 1}) \]](form_148.png)
It therefore does not need any initialization. It is most useful in situations where the inputs are counts: When one compares differences of small counts any difference may matter a lot, while small differences in large counts don't. This is what this log transformation controls for.
Definition at line 33 of file LogPlusOne.h.
Public Member Functions | |
| CLogPlusOne () | |
| virtual | ~CLogPlusOne () |
| virtual bool | init (CFeatures *f) |
| initialize preprocessor from features | |
| virtual void | cleanup () |
| cleanup | |
| virtual bool | load (FILE *f) |
| initialize preprocessor from file | |
| virtual bool | save (FILE *f) |
| save preprocessor init-data to file | |
| virtual float64_t * | apply_to_feature_matrix (CFeatures *f) |
| virtual float64_t * | apply_to_feature_vector (float64_t *f, int32_t &len) |
| virtual const char * | get_name () |
| CLogPlusOne | ( | ) |
default constructor
Definition at line 19 of file LogPlusOne.cpp.
| ~CLogPlusOne | ( | ) | [virtual] |
Definition at line 25 of file LogPlusOne.cpp.
apply preproc on feature matrix result in feature matrix return pointer to feature_matrix, i.e. f->get_feature_matrix();
Implements CSimplePreProc< float64_t >.
Definition at line 62 of file LogPlusOne.cpp.
apply preproc on single feature vector result in feature matrix
Implements CSimplePreProc< float64_t >.
Definition at line 81 of file LogPlusOne.cpp.
| void cleanup | ( | ) | [virtual] |
cleanup
clean up allocated memory
Implements CPreProc.
Definition at line 39 of file LogPlusOne.cpp.
| virtual const char* get_name | ( | void | ) | [virtual] |
| bool init | ( | CFeatures * | f | ) | [virtual] |
initialize preprocessor from features
Implements CPreProc.
Definition at line 30 of file LogPlusOne.cpp.
| bool load | ( | FILE * | f | ) | [virtual] |
initialize preprocessor from file
Definition at line 44 of file LogPlusOne.cpp.
| bool save | ( | FILE * | f | ) | [virtual] |
save preprocessor init-data to file
Definition at line 52 of file LogPlusOne.cpp.
