binj.c

Go to the documentation of this file.

/*
 * Copyright (C) 2007 Kipp Cannon, Lisa M. Goggin, Patrick Brady, Saikat
 * Ray-Majumder, Xavier Siemens
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the
 * Free Software Foundation; either version 2 of the License, or (at your
 * option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with with program; see the file COPYING. If not, write to the Free
 * Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
 * 02111-1307  USA
 */


/*
 * ============================================================================
 *
 *                                  Preamble
 *
 * ============================================================================
 */


#include <ctype.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <getopt.h>
#include <unistd.h>
#include <time.h>
#include <math.h>
#include <limits.h>
#include <gsl/gsl_rng.h>
#include <gsl/gsl_randist.h>


#include <lal/Date.h>
#include <lal/GenerateBurst.h>
#include <lal/LALConstants.h>
#include <lal/LALSimBurst.h>
#include <lal/LALStdio.h>
#include <lal/LALStdlib.h>
#include <lal/LIGOLwXML.h>
#include <lal/LIGOMetadataTables.h>
#include <lal/LIGOMetadataUtils.h>
#include <lal/TimeDelay.h>
#include <lal/TimeSeries.h>
#include <lal/XLALError.h>


#include <lalapps.h>
#include <processtable.h>


int snprintf(char *str, size_t size, const char *format, ...);


RCSID("$Id: binj.c,v 1.69 2008/04/26 02:27:33 kipp Exp $");


#define CVS_REVISION "$Revision: 1.69 $"
#define CVS_SOURCE "$Source: /usr/local/cvs/lscsoft/lalapps/src/power/binj.c,v $"
#define CVS_DATE "$Date: 2008/04/26 02:27:33 $"
#define PROGRAM_NAME "lalapps_binj"


/*
 * ============================================================================
 *
 *                                Command Line
 *
 * ============================================================================
 */


enum population {
        POPULATION_TARGETED,
        POPULATION_ALL_SKY_SINEGAUSSIAN,
        POPULATION_STRING_CUSP
};


struct options {
        INT8 gps_start_time;
        INT8 gps_end_time;
        enum population population;
        double ra;
        double dec;
        double maxA;
        double minA;
        double maxbandwidth;
        double minbandwidth;
        double maxduration;
        double minduration;
        double maxEoverr2;
        double minEoverr2;
        double maxf;
        double minf;
        double maxhrss;
        double minhrss;
        double q;
        unsigned long seed;
        double time_step;
        char *user_tag;
};


static struct options options_defaults(void)
{
        struct options defaults;
        
        defaults.gps_start_time = 0;
        defaults.gps_end_time = 0;
        defaults.population = -1;
        defaults.ra = XLAL_REAL8_FAIL_NAN;
        defaults.dec = XLAL_REAL8_FAIL_NAN;
        defaults.maxbandwidth = XLAL_REAL8_FAIL_NAN;
        defaults.minbandwidth = XLAL_REAL8_FAIL_NAN;
        defaults.maxduration = XLAL_REAL8_FAIL_NAN;
        defaults.minduration = XLAL_REAL8_FAIL_NAN;
        defaults.maxEoverr2 = XLAL_REAL8_FAIL_NAN;
        defaults.minEoverr2 = XLAL_REAL8_FAIL_NAN;
        defaults.maxf = XLAL_REAL8_FAIL_NAN;
        defaults.minf = XLAL_REAL8_FAIL_NAN;
        defaults.maxhrss = XLAL_REAL8_FAIL_NAN;
        defaults.minhrss = XLAL_REAL8_FAIL_NAN;
        defaults.minA = XLAL_REAL8_FAIL_NAN;
        defaults.maxA = XLAL_REAL8_FAIL_NAN;
        defaults.q = XLAL_REAL8_FAIL_NAN;
        defaults.seed = 0;
        defaults.time_step = 210.0 / LAL_PI;
        defaults.user_tag = NULL;

        return defaults;
}


static void print_usage(void)
{
        fprintf(stderr, 
"lalapps_binj [options]\n" 00149 "\n" 00150 "Options:\n" 00151 "\n" 00152 "--gps-end-time seconds\n" 00153 "--gps-start-time seconds\n" 00154 "       Bounds of interval in which to synthesize injections.\n" 00155 "\n" 00156 "--help\n" 00157 "       display this message\n" 00158 "\n" 00159 "--max-amplitude value\n" 00160 "--min-amplitude value\n" 00161 "       Set the bounds of the injection ampltiudes.  These only affect\n" 00162 "       string cusp injections.\n" 00163 "\n" 00164 "--max-bandwidth hertz\n" 00165 "--min-bandwidth hertz\n" 00166 "       Set the bounds of the injection bandwidthds.  These only affect\n" 00167 "       btlwnb waveforms.\n" 00168 "\n" 00169         ); fprintf(stderr, 
"--max-duration seconds\n" 00171 "--min-duration seconds\n" 00172 "       Set the bounds of the injection durations.  These only affect\n" 00173 "       btlwnb waveforms.\n" 00174 "\n" 00175 "--max-e-over-r2 value\n" 00176 "--min-e-over-r2 value\n" 00177 "       Set the bounds of the range of equivalent isotropic radiated\n" 00178 "       energies of btlwnb waveforms.  The units are M_{sun} / pc^{2} (solar\n" 00179 "       masses per parsec^{2}).\n" 00180 "\n" 00181         ); fprintf(stderr, 
"--max-frequency hertz\n" 00183 "--min-frequency hertz\n" 00184 "       Set the bounds of the injection frequencies.  These are the centre\n" 00185 "       frequencies of sine-Gaussians and btlwnb waveforms, and the\n" 00186 "       high-frequency cut-offs of string cusp waveforms.\n" 00187 "\n" 00188 "--max-hrss value\n" 00189 "--min-hrss value\n" 00190         ); fprintf(stderr, 
"       Set the bounds of the injection h_{rss} values.  These only affect\n" 00192 "       sine-Gaussian injections.  (Actually, these set the bounds of the\n" 00193 "       product of the waveform's hrss and its duration, which makes the\n" 00194 "       injections lie along the 50 efficiency curve better.  To convert to\n" 00195 "       real hrss multiply by sqrt(2) pi f/Q.) \n" 00196 "\n" 00197         ); fprintf(stderr, 
"--population name\n" 00199 "       Select the injection population to synthesize.  Allowed values are\n" 00200 "       \"targeted\", \"string_cusp\", and \"all_sky_sinegaussian\".\n" 00201 "\n" 00202 "--q value\n" 00203 "       Set the Q for sine-Gaussian injections.\n" 00204 "\n" 00205 "--ra-dec ra,dec\n" 00206 "       Set the right-ascension and declination of the sky location from which\n" 00207 "       injections should originate when generating a targeted population.\n" 00208 "       Co-ordinates are in radians.\n" 00209 "\n" 00210         ); fprintf(stderr, 
"--seed value\n" 00212 "       Set the random number generator's seed (0 = off, default = 0).\n" 00213 "\n" 00214 "--time-step value\n" 00215 "       Set the time betwen injections to value/pi seconds (default = 210).\n" 00216 "\n" 00217 "--user-tag string\n" 00218 "       Set the user tag in the process and search summary tables to this.\n"
        );
}


static ProcessParamsTable **add_process_param(ProcessParamsTable **proc_param, const ProcessTable *process, const char *type, const char *param, const char *value)
{
        *proc_param = XLALCreateProcessParamsTableRow(process);
        snprintf((*proc_param)->program, sizeof((*proc_param)->program), PROGRAM_NAME);
        snprintf((*proc_param)->type, sizeof((*proc_param)->type), type);
        snprintf((*proc_param)->param, sizeof((*proc_param)->param), "--%s", param);
        snprintf((*proc_param)->value, sizeof((*proc_param)->value), value);

        return(&(*proc_param)->next);
}

        
#define ADD_PROCESS_PARAM(process, type) \
        do { paramaddpoint = add_process_param(paramaddpoint, process, type, long_options[option_index].name, optarg); } while(0)


static struct options parse_command_line(int *argc, char **argv[], const ProcessTable *process, ProcessParamsTable **paramaddpoint)
{
        struct options options = options_defaults();
        int c;
        int option_index;
        struct option long_options[] = {
                {"gps-end-time", required_argument, NULL, 'A'},
                {"gps-start-time", required_argument, NULL, 'B'},
                {"help", no_argument, NULL, 'C'},
                {"max-amplitude", required_argument, NULL, 'D'},
                {"min-amplitude", required_argument, NULL, 'E'},
                {"max-bandwidth", required_argument, NULL, 'F'},
                {"min-bandwidth", required_argument, NULL, 'G'},
                {"max-duration", required_argument, NULL, 'H'},
                {"min-duration", required_argument, NULL, 'I'},
                {"max-e-over-r2", required_argument, NULL, 'S'},
                {"min-e-over-r2", required_argument, NULL, 'T'},
                {"max-frequency", required_argument, NULL, 'J'},
                {"min-frequency", required_argument, NULL, 'K'},
                {"max-hrss", required_argument, NULL, 'L'},
                {"min-hrss", required_argument, NULL, 'M'},
                {"population", required_argument, NULL, 'N'},
                {"q", required_argument, NULL, 'O'},
                {"ra-dec", required_argument, NULL, 'U'},
                {"seed", required_argument, NULL, 'P'},
                {"time-step", required_argument, NULL, 'Q'},
                {"user-tag", required_argument, NULL, 'R'},
                {NULL, 0, NULL, 0}
        };

        do switch(c = getopt_long(*argc, *argv, "", long_options, &option_index)) {
        case 'A':
                XLALClearErrno();
                {
                        LIGOTimeGPS tmp;
                        XLALStrToGPS(&tmp, optarg, NULL);
                        options.gps_end_time = XLALGPSToINT8NS(&tmp);
                }
                if(xlalErrno) {
                        fprintf(stderr, "invalid --%s (%s specified)\n", long_options[option_index].name, optarg);
                        exit(1);
                }
                ADD_PROCESS_PARAM(process, "lstring");
                break;

        case 'B':
                XLALClearErrno();
                {
                        LIGOTimeGPS tmp;
                        XLALStrToGPS(&tmp, optarg, NULL);
                        options.gps_start_time = XLALGPSToINT8NS(&tmp);
                }
                if(xlalErrno) {
                        fprintf(stderr, "invalid --%s (%s specified)\n", long_options[option_index].name, optarg);
                        exit(1);
                }
                ADD_PROCESS_PARAM(process, "lstring");
                break;

        case 'C':
                print_usage();
                exit(0);

        case 'D':
                options.maxA = atof(optarg);
                ADD_PROCESS_PARAM(process, "real_8");
                break;

        case 'E':
                options.minA = atof(optarg);
                ADD_PROCESS_PARAM(process, "real_8");
                break;

        case 'F':
                options.maxbandwidth = atof(optarg);
                ADD_PROCESS_PARAM(process, "real_8");
                break;

        case 'G':
                options.minbandwidth = atof(optarg);
                ADD_PROCESS_PARAM(process, "real_8");
                break;

        case 'H':
                options.maxduration = atof(optarg);
                ADD_PROCESS_PARAM(process, "real_8");
                break;

        case 'I':
                options.minduration = atof(optarg);
                ADD_PROCESS_PARAM(process, "real_8");
                break;

        case 'J':
                options.maxf = atof(optarg);
                ADD_PROCESS_PARAM(process, "real_8");
                break;

        case 'K':
                options.minf = atof(optarg);
                ADD_PROCESS_PARAM(process, "real_8");
                break;

        case 'L':
                options.maxhrss = atof(optarg);
                ADD_PROCESS_PARAM(process, "real_8");
                break;

        case 'M':
                options.minhrss = atof(optarg);
                ADD_PROCESS_PARAM(process, "real_8");
                break;

        case 'N':
                if(!strcmp(optarg, "targeted"))
                        options.population = POPULATION_TARGETED;
                else if(!strcmp(optarg, "string_cusp"))
                        options.population = POPULATION_STRING_CUSP;
                else if(!strcmp(optarg, "all_sky_sinegaussian"))
                        options.population = POPULATION_ALL_SKY_SINEGAUSSIAN;
                else {
                        fprintf(stderr, "error: unrecognized population \"%s\"", optarg);
                        exit(1);
                }
                ADD_PROCESS_PARAM(process, "lstring");
                break;

        case 'O':
                options.q = atof(optarg);
                ADD_PROCESS_PARAM(process, "real_8");
                break;

        case 'P':
                options.seed = atol(optarg);
                ADD_PROCESS_PARAM(process, "int_8u");
                break;

        case 'Q':
                options.time_step = atof(optarg) / LAL_PI;
                ADD_PROCESS_PARAM(process, "real_8");
                break;

        case 'R':
                options.user_tag = optarg;
                ADD_PROCESS_PARAM(process, "lstring");
                break;

        case 'S':
                options.maxEoverr2 = atof(optarg);
                ADD_PROCESS_PARAM(process, "real_8");
                break;

        case 'T':
                options.minEoverr2 = atof(optarg);
                ADD_PROCESS_PARAM(process, "real_8");
                break;

        case 'U':
                {
                        char *end;
                        options.ra = strtod(optarg, &end);
                        while(isspace(*end))
                                end++;
                        if(*end != ',') {
                                fprintf(stderr, "error: cannot parse --ra-dec \"%s\"\n", optarg);
                                exit(1);
                        }
                        options.dec = strtod(end + 1, &end);
                        while(isspace(*end))
                                end++;
                        if(*end != '\0') {
                                fprintf(stderr, "error: cannot parse --ra-dec \"%s\"\n", optarg);
                                exit(1);
                        }
                }
                ADD_PROCESS_PARAM(process, "lstring");
                break;

        case 0:
                /* option sets a flag */
                break;

        case -1:
                /* end of arguments */
                break;

        case '?':
                /* unrecognized option */
                print_usage();
                exit(1);

        case ':':
                /* missing argument for an option */
                print_usage();
                exit(1);
        } while(c != -1);

        /* check some of the input parameters for consistency */
        if(options.maxA < options.minA) {
                fprintf(stderr, "error: --max-amplitude < --min-amplitude\n");
                exit(1);
        }
        if(options.maxbandwidth < options.minbandwidth) {
                fprintf(stderr, "error: --max-bandwidth < --min-bandwidth\n");
                exit(1);
        }
        if(options.maxduration < options.minduration) {
                fprintf(stderr, "error: --max-duration < --min-duration\n");
                exit(1);
        }
        if(options.maxf < options.minf) {
                fprintf(stderr, "error: --max-frequency < --min-frequency\n");
                exit(1);
        }
        if(options.maxhrss < options.minhrss) {
                fprintf(stderr, "error: --max-hrss < --min-hrss\n");
                exit(1);
        }

        if(!options.gps_start_time || !options.gps_end_time) {
                fprintf(stderr, "--gps-start-time and --gps-end-time are both required\n");
                exit(1);
        }
        if(options.gps_end_time < options.gps_start_time) {
                fprintf(stderr, "error: --gps-end-time < --gps-start-time\n");
                exit(1);
        }

        return options;
}


/* 
 * ============================================================================
 *
 *                                 Sequences
 *
 * ============================================================================
 */


/*
 * Repeating arithmetic sequence.
 */


static double sequence_arithmetic_next(double low, double high, double delta)
{
        static int i = 0;
        double x = low + delta * i++;

        if(high < low || high - low < delta)
                return XLAL_REAL8_FAIL_NAN;

        if(x > high) {
                i = 1;
                return low;
        }

        return x;
}


/*
 * Repeating geometric sequence.
 */


static double sequence_geometric_next(double low, double high, double ratio)
{
        static unsigned i = 0;
        double x = low * pow(ratio, i++);

        if(high < low || high / low < ratio)
                return XLAL_REAL8_FAIL_NAN;

        if(x > high) {
                i = 1;
                return low;
        }

        return x;
}


/*
 * Random amplitude presets.
 */


static double sequence_preset_next(gsl_rng *rng)
{
        static const double presets[] = {
                1e-22,
                2e-22,
                5e-22,
                1e-21,
                2e-21,
                5e-21,
                1e-20
        };

        return presets[gsl_rng_uniform_int(rng, sizeof(presets)/sizeof(*presets))];
}


/* 
 * ============================================================================
 *
 *                Logarithmically-Distributed Random Variable
 *
 * ============================================================================
 */


/*
 * Return a random number in the range [a, b), whose logarithm is uniformly
 * distributed
 */


static double ran_flat_log(gsl_rng *rng, double a, double b)
{
        return exp(gsl_ran_flat(rng, log(a), log(b)));
}


/*
 * Logarithmically-distributed random(ish) sequence.  Same as
 * sequence_geometric_next() but where each repetition of the sequence has
 * a random factor applied whose logarithm is uniformly distributed.  The
 * result is a random variable whose logarithm is uniformly distributed on
 * average, but in which neighbouring numbers are separated by a guaranteed
 * minimum ratio.
 */


static double ran_flat_log_discrete(gsl_rng *rng, double a, double b, double ratio)
{
        static double factor = 0.0;
        double x = sequence_geometric_next(a, b / ratio, ratio);

        if(x == a)
                /* sequence has looped.  must happen first time through */
                factor = ran_flat_log(rng, 1.0, ratio);

        return x * factor;
}


/* 
 * ============================================================================
 *
 *                          String Cusp Simulations
 *
 * ============================================================================
 */


/*
 * \theta is the angle the line of sight makes with the cusp.  \theta^{2}
 * is distributed uniformly, and the high frequency cut-off of the
 * injection is \propto \theta^{-3}.  So we first solve for the limits of
 * \theta^{2} from the low- and high bounds of the frequency band of
 * interest, pick a uniformly-distributed number in that range, and convert
 * back to a high frequency cut-off.
 */


static double random_string_cusp_fhigh(double flow, double fhigh, gsl_rng *rng)
{
        const double thetasqmin = pow(fhigh, -2.0 / 3.0);
        const double thetasqmax = pow(flow, -2.0 / 3.0);
        const double thetasq = gsl_ran_flat(rng, thetasqmin, thetasqmax);

        return pow(thetasq, -3.0 / 2.0);
}


/*
 * Uniform sky location, and uniform polarization orientation.
 */


static void random_location_and_polarization(double *ra, double *dec, double *psi, gsl_rng *rng)
{
        *ra = gsl_ran_flat(rng, 0, LAL_TWOPI);
        *dec = asin(gsl_ran_flat(rng, -1, +1));
        *psi = gsl_ran_flat(rng, 0, LAL_TWOPI);
}


/*
 * Pick a random string cusp injection.
 */


static SimBurst *random_string_cusp(double flow, double fhigh, double Alow, double Ahigh, gsl_rng *rng)
{
        SimBurst *sim_burst = XLALCreateSimBurst();

        if(!sim_burst)
                return NULL;

        strcpy(sim_burst->waveform, "StringCusp");

        /* high frequency cut-off and amplitude */

        sim_burst->frequency = random_string_cusp_fhigh(flow, fhigh, rng);
        sim_burst->amplitude = ran_flat_log(rng, Alow, Ahigh);

        /* sky location and wave frame orientation */

        random_location_and_polarization(&sim_burst->ra, &sim_burst->dec, &sim_burst->psi, rng);

        /* string cusp waveform generator makes a linearly polarized
         * waveform in the + polarization.  it ignores these parameters,
         * but just for consistency we populate them appropriately */

        sim_burst->pol_ellipse_e = 1.0;
        sim_burst->pol_ellipse_angle = 0.0;

        return sim_burst;
}


/* 
 * ============================================================================
 *
 *                            Directed Simulations
 *
 * ============================================================================
 */


/*
 * Pick a random band- and time-limited white noise burst.
 */


static SimBurst *random_directed_btlwnb(double ra, double dec, double minf, double maxf, double minband, double maxband, double mindur, double maxdur, double minEoverr2, double maxEoverr2, gsl_rng *rng)
{
        REAL8TimeSeries *hplus, *hcross;
        SimBurst *sim_burst = XLALCreateSimBurst();

        if(!sim_burst)
                return NULL;

        strcpy(sim_burst->waveform, "BTLWNB");

        /* sky location and wave frame orientation */

        sim_burst->ra = ra;
        sim_burst->dec = dec;
        sim_burst->psi = gsl_ran_flat(rng, 0, LAL_TWOPI);

        /* pick a waveform */
        /* FIXME:  this should be ULONG_MAX but metaio can't handle
         * unsigned ints yet */

        sim_burst->waveform_number = floor(gsl_ran_flat(rng, 0, LONG_MAX));

        /* centre frequency.  three steps between minf and maxf */

        sim_burst->frequency = ran_flat_log_discrete(rng, minf, maxf, pow(maxf / minf, 1.0 / 3.0));

        /* duration and bandwidth.  keep picking until a valid pair is
         * obtained (i.e. their product is >= 2 / \pi) */

        do {
                sim_burst->duration = ran_flat_log(rng, mindur, maxdur);
                sim_burst->bandwidth = ran_flat_log(rng, minband, maxband);
        } while(sim_burst->bandwidth * sim_burst->duration < LAL_2_PI);

        /* energy */

        sim_burst->egw_over_rsquared = ran_flat_log(rng, minEoverr2, maxEoverr2) * pow(sim_burst->frequency / 100.0, 4.0);

        /* populate the hrss column for convenience later */
        /* FIXME:  sample rate is hard-coded to 8192 Hz, which is what the
         * excess power pipeline's .ini file is configured for in CVS, but
         * because it can be easily changed this is not good */

        XLALGenerateSimBurst(&hplus, &hcross, sim_burst, 1.0 / 8192);
        sim_burst->hrss = XLALMeasureHrss(hplus, hcross);
        XLALDestroyREAL8TimeSeries(hplus);
        XLALDestroyREAL8TimeSeries(hcross);

        /* not sure if this makes sense.  these parameters are ignored by
         * the injection code, but post-processing tools sometimes wish to
         * know with what amplitude an injection should've been seen in an
         * instrument, and they use these to project the + and x amplitudes
         * onto the detector.  setting the eccentricity to 0 and the angle
         * to anything makes such tools believe the amplitude is equally
         * partitioned between the two polarizations which is true for
         * these injections. */

        sim_burst->pol_ellipse_e = 0.0;
        sim_burst->pol_ellipse_angle = 0.0;

        /* done */

        return sim_burst;
}


/* 
 * ============================================================================
 *
 *                           All-Sky sine-Gaussians
 *
 * ============================================================================
 */


/*
 * the duration of a sine-Gaussian from its Q and centre frequency
 */


static double duration_from_q_and_f(double Q, double f)
{
        /* compute duration from Q and frequency */
        return Q / (sqrt(2.0) * LAL_PI * f);
}


/*
 * pick a sine-Gaussian
 */


static SimBurst *random_all_sky_sineGaussian(double minf, double maxf, double q, double minhrsst, double maxhrsst, gsl_rng *rng)
{
        SimBurst *sim_burst = XLALCreateSimBurst();

        if(!sim_burst)
                return NULL;

        strcpy(sim_burst->waveform, "SineGaussian");

        /* sky location and wave frame orientation */

        random_location_and_polarization(&sim_burst->ra, &sim_burst->dec, &sim_burst->psi, rng);

        /* q and centre frequency.  three steps between minf and maxf */

        sim_burst->q = q;
        sim_burst->frequency = ran_flat_log_discrete(rng, minf, maxf, pow(maxf / minf, 1.0 / 3.0));

        /* hrss */

        sim_burst->hrss = ran_flat_log(rng, minhrsst, maxhrsst) / duration_from_q_and_f(sim_burst->q, sim_burst->frequency);

        /* hard-code for linearly polarized waveforms in the x
         * polarization.  induces LAL's sine-Gaussian generator to produce
         * linearly polarized sine-Gaussians (+ would be a cosine
         * Gaussian). */

        sim_burst->pol_ellipse_e = 1.0;
        sim_burst->pol_ellipse_angle = LAL_PI_2;

        /* done */

        return sim_burst;
}


/* 
 * ============================================================================
 *
 *                                   Output
 *
 * ============================================================================
 */


static void write_xml(const ProcessTable *process_table_head, const ProcessParamsTable *process_params_table_head, const SearchSummaryTable *search_summary_head, const SimBurst *sim_burst, struct options options)
{
        LALStatus status = blank_status;
        char fname[256];
        LIGOLwXMLStream xmlfp;

        memset(&xmlfp, 0, sizeof(xmlfp));

        if(options.user_tag)
                snprintf(fname, sizeof(fname), "HL-INJECTIONS_%s-%d-%d.xml", options.user_tag, (int) (options.gps_start_time / LAL_INT8_C(1000000000)), (int) ((options.gps_end_time - options.gps_start_time) / LAL_INT8_C(1000000000)));
        else
                snprintf(fname, sizeof(fname), "HL-INJECTIONS-%d-%d.xml", (int) (options.gps_start_time / LAL_INT8_C(1000000000)), (int) ((options.gps_end_time - options.gps_start_time) / LAL_INT8_C(1000000000)));

        LAL_CALL(LALOpenLIGOLwXMLFile(&status, &xmlfp, fname), &status);

        /* process table */
        if(XLALWriteLIGOLwXMLProcessTable(&xmlfp, process_table_head)) {
                /* error occured.  ?? do anything else ?? */
                exit(1);
        }

        /* process params table */
        if(XLALWriteLIGOLwXMLProcessParamsTable(&xmlfp, process_params_table_head)) {
                /* error occured.  ?? do anything else ?? */
                exit(1);
        }

        /* search summary table */
        if(XLALWriteLIGOLwXMLSearchSummaryTable(&xmlfp, search_summary_head)) {
                /* error occured.  ?? do anything else ?? */
                exit(1);
        }

        /* sim burst table */
        if(XLALWriteLIGOLwXMLSimBurstTable(&xmlfp, sim_burst)) {
                /* error occured.  ?? do anything else ?? */
                exit(1);
        }

        LAL_CALL(LALCloseLIGOLwXMLFile(&status, &xmlfp), &status);
}


/* 
 * ============================================================================
 *
 *                                Entry Point
 *
 * ============================================================================
 */


int main(int argc, char *argv[])
{
        struct options options;
        INT8 tinj;
        gsl_rng *rng;
        ProcessTable *process_table_head;
        ProcessParamsTable *process_params_table_head = NULL;
        SearchSummaryTable *search_summary_head;
        SimBurst *sim_burst_table_head = NULL;
        SimBurst **sim_burst = &sim_burst_table_head;


        /*
         * Initialize debug handler
         */


        lal_errhandler = LAL_ERR_EXIT;
        lalDebugLevel = LALINFO | LALWARNING | LALERROR | LALNMEMDBG | LALNMEMPAD | LALNMEMTRK;


        /*
         * Process table
         */


        process_table_head = XLALCreateProcessTableRow();
        if(XLALPopulateProcessTable(process_table_head, PROGRAM_NAME, CVS_REVISION, CVS_SOURCE, CVS_DATE, 0))
                exit(1);
        XLALGPSTimeNow(&process_table_head->start_time);
        snprintf(process_table_head->ifos, sizeof(process_table_head->ifos), "H1,H2,L1");


        /*
         * Command line and process params table.
         */


        options = parse_command_line(&argc, &argv, process_table_head, &process_params_table_head);
        if(options.user_tag)
                snprintf(process_table_head->comment, sizeof(process_table_head->comment), "%s", options.user_tag);


        /*
         * Search summary table
         */


        search_summary_head = XLALCreateSearchSummaryTableRow(process_table_head);
        if(options.user_tag)
                snprintf(search_summary_head->comment, sizeof(search_summary_head->comment), "%s", options.user_tag);
        search_summary_head->nnodes = 1;
        search_summary_head->out_start_time = *XLALINT8NSToGPS(&search_summary_head->in_start_time, options.gps_start_time);
        search_summary_head->out_end_time = *XLALINT8NSToGPS(&search_summary_head->in_end_time, options.gps_end_time);
        snprintf(search_summary_head->ifos, sizeof(search_summary_head->ifos), process_table_head->ifos);


        /*
         * Initialize random number generator
         */


        rng = gsl_rng_alloc(gsl_rng_mt19937);
        if(options.seed)
                gsl_rng_set(rng, options.seed);


        /*
         * Main loop
         */


        for(tinj = options.gps_start_time; tinj <= options.gps_end_time; tinj += options.time_step * 1e9) {
                /*
                 * Progress bar.
                 */

                XLALPrintInfo("%s: ", argv[0]);
                XLALPrintProgressBar((tinj - options.gps_start_time) / (double) (options.gps_end_time - options.gps_start_time));
                XLALPrintInfo(" complete\n");

                /*
                 * Create an injection
                 */

                switch(options.population) {
                case POPULATION_TARGETED:
                        *sim_burst = random_directed_btlwnb(options.ra, options.dec, options.minf, options.maxf, options.minbandwidth, options.maxbandwidth, options.minduration, options.maxduration, options.minEoverr2, options.maxEoverr2, rng);
                        break;

                case POPULATION_ALL_SKY_SINEGAUSSIAN:
                        *sim_burst = random_all_sky_sineGaussian(options.minf, options.maxf, options.q, options.minhrss, options.maxhrss, rng);
                        break;

                case POPULATION_STRING_CUSP:
                        *sim_burst = random_string_cusp(options.minf, options.maxf, options.minA, options.maxA, rng);
                        break;
                }

                if(!*sim_burst) {
                        XLALPrintError("can't make injection");
                        exit(1);
                }

                /*
                 * Peak time at geocentre in GPS seconds
                 */

                XLALINT8NSToGPS(&(*sim_burst)->time_geocent_gps, tinj);

                /*
                 * Peak time at geocentre in GMST radians
                 */

                (*sim_burst)->time_geocent_gmst = XLALGreenwichMeanSiderealTime(&(*sim_burst)->time_geocent_gps);

                /*
                 * Move to next injection
                 */

                sim_burst = &(*sim_burst)->next;
        }

        /* output */

        XLALGPSTimeNow(&process_table_head->end_time);
        search_summary_head->nevents = XLALSimBurstAssignIDs(sim_burst_table_head, process_table_head->process_id, 0);
        write_xml(process_table_head, process_params_table_head, search_summary_head, sim_burst_table_head, options);

        /* done */

        gsl_rng_free(rng);
        XLALDestroyProcessTable(process_table_head);
        XLALDestroyProcessParamsTable(process_params_table_head);
        XLALDestroySearchSummaryTable(search_summary_head);
        XLALDestroySimBurstTable(sim_burst_table_head);
        exit(0);
}

---