IMP  2.0.1
The Integrative Modeling Platform
IMP::em::CoarseCCatIntervals Class Reference

Cross correlation coefficient calculator. More...

#include <IMP/em/CoarseCCatIntervals.h>

+ Inheritance diagram for IMP::em::CoarseCCatIntervals:

Public Member Functions

 CoarseCCatIntervals (const int &ncd)
 
std::pair< double,
algebra::Vector3Ds
evaluate (DensityMap *em_map, SampledDensityMap *model_map, const algebra::Vector3Ds &deriv, float scalefac, bool lderiv, unsigned long eval_interval)
 Evaluate the cross-correlation value only every X calls to the function. More...
 

Protected Member Functions

void allocate_derivatives_array (int ncd)
 

Protected Attributes

int calls_counter_
 Number of times the evaluation has been called. More...
 
bool dv_memory_allocated_
 
float stored_cc_
 Stored correlation value.
 
double * stored_dvx_
 Stored derivative terms.
 
double * stored_dvy_
 
double * stored_dvz_
 

Additional Inherited Members

- Static Public Member Functions inherited from IMP::em::CoarseCC
static double cross_correlation_coefficient (const DensityMap *grid1, const DensityMap *grid2, float grid2_voxel_data_threshold, bool allow_padding=false, FloatPair norm_factors=FloatPair(0., 0.))
 Calculates the cross correlation coefficient between two maps. More...
 
static float local_cross_correlation_coefficient (const DensityMap *em_map, DensityMap *model_map, float voxel_data_threshold)
 Local cross correlation function.
 

Detailed Description

Store CCC and derivative values and recompute then every X steps.

Definition at line 21 of file CoarseCCatIntervals.h.

Member Function Documentation

std::pair<double,algebra::Vector3Ds> IMP::em::CoarseCCatIntervals::evaluate ( DensityMap em_map,
SampledDensityMap model_map,
const algebra::Vector3Ds deriv,
float  scalefac,
bool  lderiv,
unsigned long  eval_interval 
)
Evaluates the value of the cross correlation term
but only at given intervals to save computation time.
Otherwise, the same value is returned.
This function has an special behavior, as it
does not return the true cross correlation coefficient ccc,
but the value:  scalefac*(1-ccc)

The reason why is to use this term as part of an scoring
function that is better the lower the term.
If you want the cross correlation coefficient,
use cross_correlation_coefficient() instead.
Parameters
[in]em_mapexp EM map
Note
correct RMSD and mean MUST be in the header!
Parameters
[in]model_mapan empty map that will contain the sampled particles in the access_p
[in]scalefacscale factor to apply to the value of the cross correlation term
[in]derivinput derivatives (only the size is used)
[in]lderivif true, the derivatives of the term are computed
[in]eval_intervalthe number of times the function is going to return the same value before computing the values again
Returns
the value of the cross correlation term: scalefac * (1-CCC) and a vector of derivatives

Member Data Documentation

int IMP::em::CoarseCCatIntervals::calls_counter_
protected

The evaluation is only performed the first time and when calls_counter reaches eval_interval. Otherwise the stored_cc_ value is returned

Definition at line 69 of file CoarseCCatIntervals.h.


The documentation for this class was generated from the following file: