Here is the output from the phase_evoltn example:
GRASP: Message from function phase_frequency() at line number 439 of file "pN_chirp.c". Frequency evolution no longer monotonic. Phase evolution terminated at frequency and step: 911.681702 13357 Terminating chirp. Termination code set to: 1201 Returning to calling routine. $Id: man_inspiral.tex,v 1.42 1999/09/29 19:44:41 ballen Exp $ $Name: $ m1=1.400000 m2=1.400000 Initial_Freq=60.000000 steps_filld=13357 steps_alloc=16384 Max_Freq_Actual=911.681702 time_in_band=1.353408 clscnc_time=1.353573 Termination code: 1201 0 0.000000 0.000000 60.000000 1 0.000101 0.038204 60.001675 2 0.000203 0.076369 60.003353 3 0.000304 0.114627 60.005020 4 0.000405 0.152820 60.006695 5 0.000507 0.191071 60.008366 6 0.000608 0.229173 60.010052 ... ... ... ... 13349 1.352699 797.669800 720.294189 13350 1.352800 798.134949 741.157715 13351 1.352901 798.614136 764.565796 13352 1.353003 799.109192 791.015686 13353 1.353104 799.622192 821.015320 13354 1.353205 800.155457 854.720337 13355 1.353307 800.710999 890.133667 13356 1.353408 801.286499 911.681702
The first seven lines of output come directly from phase_frequency(), and are printed to stderr. These give a warning message telling why the chirp calculation was terminated; it no longer had monotonically increasing frequency. It also tells where the chirp was terminated; after computing 13357 points it has reached a frequency of 907Hz. The termination code (1201) is also printed. Knowing the termination code makes it easy to find the segment of source code that produced the termination; just do a search for the character string ``1201'' and you will find the line of code where the termination code was set. Setting err_cd_sprs greater than 1201 would suppress the printing of this warning message and all messages with a termination code less than 1201. However, even without the printed message the calling routine can determine the value of the termination code; it is returned by phase_frequency().
The rest of the output comes from the phase_evoltn program. The quantity time_in_bandsteps_filldSample_Time is the length (in seconds) of the computed chirp. The quantity clscnc_time is the value of that enters Eqs.() below. The four column output from left to right is the integer index of the data points, time stamp of each point in seconds (starting arbitrarily from zero), the orbital phase in radians (starting arbitrarily from zero), and the orbital frequency (starting from the initial frequency of 60Hz).
To summarize: It takes about 1.35 seconds for two 1.4 objects to spiral in from an orbital frequency of 60Hz to an orbital frequency of 911Hz. The chirp calculation was terminated at 911Hz - instead of the requested 2000Hz - because the post-Newtonian expression used to compute the chirp is clearly out of its region of validity: the frequency is no longer increasing. Examining the last few data points shows that the frequency was rising quickly - as expected - until the last two data points. During this inspiral the orbital system went through 811.09 127.53 revolutions. The two integer numbers steps_filld and steps_alloc are the number of actual data points computed and the number of floating point memory slots allocated, respectively. (Memory is allocated in blocks of 4096 floats at a time. Thus steps_alloc will generally exceed steps_filld.) The values of the phase and frequency at every Sample_Time seconds starting from when the binary had an orbital frequency of 60Hz until it neared ``coalescence'' at 911Hz have been calculated.