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Example: tfmain program

This program was used to test the alogorithm described in the Introduction (see section [*]. We generate coloured Gaussian noise and compute the TF map of each data subsegment and then search for one dimensional structures in the map. The overall structure of the code is as follows. We use MPI code to set up a master slave operation. We have a single master which generates data segments containing simulated Gaussian noise with a signal embedded in the segment at an SNR as specified in the input file (tfmain.in). Data segments containing only noise are generated by setting SNR = $0.0$. These segments are then passed on to the slaves who compute the TF maps, detect the lines in each map and write the output files directly to disk. In order to reduce the communication overheads, the slaves compute many TF maps before they request for more data. Each segment of data contains many subsegments of data. The slave computes the the TF map and detects the lines therein for every subsegment in the segment successively.

The program is divided into the following files:

tfmain.h: A header file containing function prototypes and parameters.
tfmain.c: The main program containing MPI code and organizing the data flow.
tf_get_data.c: Routines to generate Gaussian random noise and insert a signal at a given SNR.
tf_misc.c: Miscellaneous routines.
randomseeds: Contains a single column of random number seeds.
tfmain.in: An input file containing various parameters read in by the program.
MergeSig.dat: This file contains a single column of floating point numbers and these are equally spaced samples of the coalescence waveform for a pair of $30M_\odot$ blackholes. The sampling frequency is 9868.4209 Hz. In addition we also include coalescence waveforms for binaries in the mass range $45M_\odot - 70M_\odot$. These files are called MergeSig.dat.* where * is a wildcard denoting the total mass of the binary.
combine.c: A program to combine the various output files produced during a run. The original output files are deleted and all the output information is written to a single file.
readertf.c: A program to interpret the file produced by combine.c.



Subsections
next up previous contents
Next: Environment variables used by Up: GRASP Routines: Time-Frequency Methods Previous: Function: get_lines()   Contents
Bruce Allen 2000-11-19