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NumCosmo Reference Manual | ![]() |
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Top | Description | Object Hierarchy |
Window Function Abstract ClassWindow Function Abstract Class — Defines the prototype of the NcWindow object. |
Synopsis
struct NcWindow; struct NcWindowClass; void nc_window_clear (NcWindow **wf
); gdouble nc_window_deriv_fourier (const NcWindow *wf
,const gdouble k
,const gdouble R
); gdouble nc_window_eval_fourier (const NcWindow *wf
,const gdouble k
,const gdouble R
); gdouble nc_window_eval_realspace (const NcWindow *wf
,const gdouble r
,const gdouble R
); void nc_window_free (NcWindow *wf
); NcWindow * nc_window_new_from_name (gchar *window_name
); gdouble nc_window_volume (NcWindow *wf
);
Description
This module comprises the set of functions to compute the window function in both real and Fourier spaces as well as its derivative with respect to the scale $R$ in Fourier space.
In order to study the statistical properties of the density fluctuation field at a certain scale $R$, we use the window function. As an example, to compute the variance of the density contrast at scale $R$, we convolve the window function in the Fourier space with the power spectrum.
Details
nc_window_clear ()
void nc_window_clear (NcWindow **wf
);
Atomically decrements the reference count of wf
by one. If the reference count drops to 0,
all memory allocated by wf
is released. Set the pointer to NULL;
|
a NcWindow. |
nc_window_deriv_fourier ()
gdouble nc_window_deriv_fourier (const NcWindow *wf
,const gdouble k
,const gdouble R
);
This function returns the derivative with respect to R of the window function in the Fourier space.
|
a NcWindow. |
|
mode. |
|
scale. |
Returns : |
The value of the first derivative of the window function in the Fourier space at scale R . |
nc_window_eval_fourier ()
gdouble nc_window_eval_fourier (const NcWindow *wf
,const gdouble k
,const gdouble R
);
This function computes the window function in the Fourier space.
|
a NcWindow. |
|
mode. |
|
scale. |
Returns : |
The value of the window function in the Fourier space at scale R . |
nc_window_eval_realspace ()
gdouble nc_window_eval_realspace (const NcWindow *wf
,const gdouble r
,const gdouble R
);
This function computes the window function in real space.
|
a NcWindow. |
|
distance module to the center point of the filtered region. |
|
scale. |
Returns : |
The value of the window function in the real space at scale R . |
nc_window_free ()
void nc_window_free (NcWindow *wf
);
Atomically decrements the reference count of wf
by one. If the reference count drops to 0,
all memory allocated by wf
is released.
|
a NcWindow. |
nc_window_new_from_name ()
NcWindow * nc_window_new_from_name (gchar *window_name
);
This function returns a new NcWindow whose type is defined by window_name
string.
|
"NcWindowTophat" or "NcWindowGaussian". |
Returns : |
A new NcWindow. |
nc_window_volume ()
gdouble nc_window_volume (NcWindow *wf
);
This function returns the volume of the region (with radius 1) defined by the window function.
Top-hat volume: NC_WINDOW_VOLUME_TOPHAT.
Gaussian volume: NC_WINDOW_VOLUME_GAUSSIAN.
|
a NcWindow. |
Returns : |
The volume (with radius 1) defined by wf . |