NcmStatsDistVKDE: NumCosmo Reference Manual

NcmStatsDistVKDE

NcmStatsDistVKDE — Abstract class for implementing N-dimensional probability distributions with a variable density estimator kernel.

Functions

NcmStatsDistVKDE *	ncm_stats_dist_vkde_new ()
NcmStatsDistVKDE *	ncm_stats_dist_vkde_ref ()
void	ncm_stats_dist_vkde_free ()
void	ncm_stats_dist_vkde_clear ()
void	ncm_stats_dist_vkde_set_local_frac ()
gdouble	ncm_stats_dist_vkde_get_local_frac ()
void	ncm_stats_dist_vkde_set_use_rot_href ()
gboolean	ncm_stats_dist_vkde_get_use_rot_href ()

Properties

double	local-frac	Read / Write / Construct
gboolean	use-rot-href	Read / Write / Construct

Types and Values

#define	NCM_TYPE_STATS_DIST_VKDE
struct	NcmStatsDistVKDEClass
	NcmStatsDistVKDE

Object Hierarchy

    GObject
    ╰── NcmStatsDist
        ╰── NcmStatsDistKDE
            ╰── NcmStatsDistVKDE

Description

Abstract object to reconstruct an arbitrary N-dimensional probability distribution. This object provides the complementary tools to perform a radial basis interpolation in a multidimensional function using the NcmStatsDist class.

This object sets the kernel $\phi$ to be used in the radial basis interpolation. This object also implements some calculations needed in the NcmStatsDist class, such as the covariance matrices of the whole sample points and its Cholesky decompositions, the preparation of the interpolation matrix $IM$, the kernel normalization factors, and given a sample vector $\vec{x}$, the distribution evaluated in these points. Some of these calculations are explained below.

The NcmStatsDistVKDE uses a different covariance matrix for each sample point. This feature is computed in the ncm_stats_dist_prepare_kernel() function. In this algorithm, one should define the local_frac parameter, that is, the fraction of nearest sample points that will be used to compute each covariance matrix of each sample point. This is done by calling the function ncm_stats_dist_vkde_set_local_frac(). The rest of the calculation follows the same procedure as the NcmStatsDist and NcmStatsDistKDE objects, using now a different covariance matrix and normalization factor for each kernel. For more information about how the NcmStatsDist class works, check NcmStatsDist and NcmStatsDistKDE objects.

The user must provide input the values: sdk , CV_type - ncm_stats_dist_vkde_new(), y - ncm_stats_dist_add_obs(), split_frac - ncm_stats_dist_set_split_frac(), over_smooth - ncm_stats_dist_set_over_smooth(), local_Frac - ncm_stats_dist_vkde_set_local_frac(), $v(x)$ - ncm_stats_dist_prepare_interp(). To see an example of how to use this object and the main functions that are called within each function, check the fluxogram at the end of this documentation, where the order of the functions that should be called by the user and some of the functions that the algorithm calls.

vkde_sketch

Functions

ncm_stats_dist_vkde_new ()

NcmStatsDistVKDE *
ncm_stats_dist_vkde_new (NcmStatsDistKernel *sdk,
                         NcmStatsDistCV CV_type);

Creates a new NcmStatsDistVKDE object using sdk as kernel and CV_type as cross-validation method.

Parameters

sdk	a NcmStatsDistKernel
CV_type	a NcmStatsDistCV

Returns

the newly created NcmStatsDistVKDE object.

[transfer full]

ncm_stats_dist_vkde_ref ()

NcmStatsDistVKDE *
ncm_stats_dist_vkde_ref (NcmStatsDistVKDE *sdvkde);

Increases the reference count of sdvkde .

Parameters

sdvkde

a NcmStatsDistVKDE

Returns

sdvkde .

[transfer full]

ncm_stats_dist_vkde_free ()

void
ncm_stats_dist_vkde_free (NcmStatsDistVKDE *sdvkde);

Decreases the reference count of sdvkde .

Parameters

sdvkde

a NcmStatsDistVKDE

ncm_stats_dist_vkde_clear ()

void
ncm_stats_dist_vkde_clear (NcmStatsDistVKDE **sdvkde);

Decreases the reference count of *sdvkde and sets the pointer *sdvkde to NULL.

Parameters

sdvkde

a NcmStatsDistVKDE

ncm_stats_dist_vkde_set_local_frac ()

void
ncm_stats_dist_vkde_set_local_frac (NcmStatsDistVKDE *sdvkde,
                                    const gdouble local_frac);

Sets local kernel fraction to local_frac . This fraction defines the amount of closest points from each sample point that will be used to compute the covariance matrix of each point.

Parameters

sdvkde	a NcmStatsDistVKDE
local_frac	the over-smooth factor

ncm_stats_dist_vkde_get_local_frac ()

gdouble
ncm_stats_dist_vkde_get_local_frac (NcmStatsDistVKDE *sdvkde);

Parameters

sdvkde

a NcmStatsDistVKDE

Returns

a double local_frac , the local kernel fraction.

ncm_stats_dist_vkde_set_use_rot_href ()

void
ncm_stats_dist_vkde_set_use_rot_href (NcmStatsDistVKDE *sdvkde,
                                      const gboolean use_rot_href);

Sets whether to use the rule of thumb bandwidth for the

Parameters

sdvkde	a NcmStatsDistVKDE
use_rot_href	whether to use the rule of thumb bandwidth

ncm_stats_dist_vkde_get_use_rot_href ()

gboolean
ncm_stats_dist_vkde_get_use_rot_href (NcmStatsDistVKDE *sdvkde);

Parameters

sdvkde

a NcmStatsDistVKDE

Returns

whether to use the rule of thumb bandwidth.

Types and Values

NCM_TYPE_STATS_DIST_VKDE

#define NCM_TYPE_STATS_DIST_VKDE (ncm_stats_dist_vkde_get_type ())

struct NcmStatsDistVKDEClass

struct NcmStatsDistVKDEClass {
};