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Structure: struct chirp_space

The following data structure, when fully assigned, contains complete information about a region of the parameter space of chirp signals: it describes the extent of the region, the coordinates used on it, the behaviour of the match function over it, and the number and location of chirp templates covering it. It is assumed that the templates will be placed using coordinates $x,y$ which are related to the $\tau_0,\tau_1$ coordinates by a simple rotation; for the best results, the $x,y$ axes should be roughly aligned with the principle axes of the elliptical equimatch contours discussed in section [*]. The fields of this structure are:

struct chirp_space {

float m_mn; The minimum mass of a binary component in the parameter space (solar masses).

float m_mx; The maximum mass of a binary component in the parameter space (solar masses).

float ftau; The reference frequency used to define the $\tau_0,\tau_1$ coordinates.

float angle; The angle (radians) counterclockwise from the $\tau_0$ axis to the $x$ coordinate axis used in placing the template patches.

float match; The minimum match level of the covering template patches.

int n_bound; The number of points used to define the boundary of the region.

double *x_bound; An array [0..n_bound] containing the $x$ coordinates of the points defining the boundary. The array is of length n_bound+1, but the index values [0] and [n_bound] should refer to the same point, so as to define an explicitly closed polygon.

double *y_bound; An array [0..n_bound] as above, but the $y$ coordinates.

struct cubic_grid grid; A data structure containing coefficients of a cubic fit to the match function, evaluated on a grid of points in the parameter space, plus related information. See the documentation for the struct cubic_grid data structure in section [*].

int n_templates; The number of template patches covering the space.

struct chirp_template *templates; An array [0..n_templates-1] of data structures describing the positions of the covering templates. See the next section for a descrition of these data structures.

};


next up previous contents
Next: Structure: struct chirp_template Up: GRASP Routines: Template Bank Previous: Constants in tiling_2d.c   Contents
Bruce Allen 2000-11-19