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Function: splitup()

0 void splitup(float *working, float template, float *r, int n, float total, int p, int *indices)
This routine takes as inputs a template and a noise-power spectrum, and splits up the frequency spectrum into a set of sub-intervals to use with the vetoing technique just described.

The arguments are:

working: Input. An array working[0..n-1] used for working space.
template: Input. The array template[0..n-1] contains the positive frequency ($f \ge 0$) part of the complex function $\tilde T(f)$. The packing of $\tilde T$ into this array follows the scheme used by the Numerical Recipes routine realft(), which is described between equations (12.3.5) and (12.3.6) of [1]. The DC component $\tilde T(0)$ is real, and located in template[0]. The Nyquist-frequency component $\tilde T(f_{\rm Nyquist})$ is also real, and is located in template[1]. The array elements template[2] and template[3] contain the real and imaginary parts, respectively, of $\tilde T(\Delta f)$ where $\Delta f = 2 f_{\rm Nyquist}/n = (n
\Delta t)^{-1}$. Array elements template[2j] and template[2j+1] contain the real and imaginary parts of $\tilde T( j \; \Delta f)$ for $j=1,\cdots,n/2-1$.
r: Input. The array r[0..n/2] contains the values of the real function $\tilde r$ which is twice the inverse of the receiver noise, as in equation ([*]), so that $\tilde r(f) = 2/\tilde
S_h(\vert f\vert)$. The array elements are arranged in order of increasing frequency, from the DC value at subscript 0, to the Nyquist frequency at subscript n/2. Thus, the $j$'th array element r[j] contains the real value $\tilde r(j \; \Delta f)$, for $j=0,1,\cdots,n/2$. Again it is assumed that $\tilde r(-f) = \tilde r^*(f) = \tilde r(f)$.
n: Input. The total length of the complex arrays template and working, and the number of points in the output array s. Note that the array r contains $n/2+1$ points. n must be even.
total: Input. This is the total value of the integrated template squared over $S_h$; the frequency subintervals are choose so that each of the p subintervals contains $1/p$ of this total.
p: Input. The number of frequency bands into which you want to divide the range from DC to $f_{\rm Nyquist}$.
indices: Ouput. The frequency bins of the first frequency band are i=0..indices[0]. The next frequency band is i=indices[0]+1..indices[1]. The p'th frequency band is i=indices[p-2]+1..indices[p-1]. Note that indices[p-1]=n-1.
Author: Bruce Allen, ballen@dirac.phys.uwm.edu
Comments: None.


next up previous contents
Next: Function: splitup_freq() Up: GRASP Routines: Gravitational Radiation Previous: How does the test   Contents
Bruce Allen 2000-11-19