IMP::em::CoarseCCatIntervals Class Reference

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Detailed Description

Cross correlation coefficient calculator.

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

Inheritance diagram for IMP::em::CoarseCCatIntervals:

List of all members.

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.

Static Public Member Functions
static CoarseCCatIntervals *	get_from (IMP::base::Object *o)
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.
static float	local_cross_correlation_coefficient (const DensityMap *em_map, DensityMap *model_map, float voxel_data_threshold)
	Local cross correlation function.

Protected Member Functions
void	allocate_derivatives_array (int ncd)

Protected Attributes
int	calls_counter_
	Number of times the evaluation has been called.
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
Related Functions inherited from IMP::em::CoarseCC
static float	calc_score (DensityMap *data, SampledDensityMap *model_map, float scalefactor, bool recalc_rms=true, bool resample=true, FloatPair norm_factors=FloatPair(0., 0.))
	Calculates the value of the EM fitting term.

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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
	)

Evaluate the cross-correlation value only every X calls to the function.

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_map

exp EM map

Note:

correct RMSD and mean MUST be in the header!

Parameters:

[in]	model_map	an empty map that will contain the sampled particles in the access_p
[in]	dvx	to contain the x partial derivatives
[in]	dvy	to contain the y partial derivatives
[in]	dvz	to contain the z partial derivatives
[in]	scalefac	scale factor to apply to the value of the cross correlation term
[in]	lderiv	if true, the derivatives of the term are computed
[in]	eval_interval	the 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)

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Member Data Documentation

int IMP::em::CoarseCCatIntervals::calls_counter_

protected

Number of times the evaluation has been called.

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

float IMP::em::CoarseCCatIntervals::stored_cc_

protected

Stored correlation value.

double* IMP::em::CoarseCCatIntervals::stored_dvx_

protected

Stored derivative terms.

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

• CoarseCCatIntervals.h