Ejemplo n.º 1
0
/***********************************************************************//**
 * @brief Test CTA Npred computation
 *
 * Tests the Npred computation for the diffuse source model. This is done
 * by loading the model from the XML file and by calling the
 * GCTAObservation::npred method which in turn calls the
 * GCTAResponse::npred_diffuse method. The test takes a few seconds.
 ***************************************************************************/
void TestGCTAResponse::test_response_npred_diffuse(void)
{
    // Set reference value
    double ref = 11212.26274;

    // Set parameters
    double src_ra  = 201.3651;
    double src_dec = -43.0191;
    double roi_rad =   4.0;

    // Setup ROI centred on Cen A with a radius of 4 deg
    GCTARoi     roi;
    GCTAInstDir instDir;
    instDir.radec_deg(src_ra, src_dec);
    roi.centre(instDir);
    roi.radius(roi_rad);

    // Setup pointing on Cen A
    GSkyDir skyDir;
    skyDir.radec_deg(src_ra, src_dec);
    GCTAPointing pnt;
    pnt.dir(skyDir);

    // Setup dummy event list
    GGti     gti;
    GEbounds ebounds;
    GTime    tstart(0.0);
    GTime    tstop(1800.0);
    GEnergy  emin;
    GEnergy  emax;
    emin.TeV(0.1);
    emax.TeV(100.0);
    gti.append(tstart, tstop);
    ebounds.append(emin, emax);
    GCTAEventList events;
    events.roi(roi);
    events.gti(gti);
    events.ebounds(ebounds);

    // Setup dummy CTA observation
    GCTAObservation obs;
    obs.ontime(1800.0);
    obs.livetime(1600.0);
    obs.deadc(1600.0/1800.0);
    obs.response(cta_irf, cta_caldb);
    obs.events(&events);
    obs.pointing(pnt);

    // Load models for Npred computation
    GModels models(cta_rsp_xml);

    // Perform Npred computation
    double npred = obs.npred(models, NULL);

    // Test Npred
    test_value(npred, ref, 1.0e-5, "Diffuse Npred computation");

    // Return
    return;
}
Ejemplo n.º 2
0
/***********************************************************************//**
 * @brief Test CTA psf computation
 *
 * The Psf computation is tested by integrating numerically the Psf
 * function. Integration is done in a rather simplistic way, by stepping
 * radially away from the centre. The integration is done for a set of
 * energies from 0.1-10 TeV.
 ***************************************************************************/
void TestGCTAResponse::test_response_psf(void)
{
    // Load response
    GCTAResponse rsp;
    rsp.caldb(cta_caldb);
    rsp.load(cta_irf);

    // Integrate Psf
    GEnergy eng;
    for (double e = 0.1; e < 10.0; e *= 2.0) {
        eng.TeV(e);
        double r     = 0.0;
        double dr    = 0.001;
        int    steps = int(1.0/dr);
        double sum   = 0.0;
        for (int i = 0; i < steps; ++i) {
            r   += dr;
            sum += rsp.psf(r*deg2rad, 0.0, 0.0, 0.0, 0.0, eng.log10TeV()) *
                   twopi * std::sin(r*deg2rad) * dr*deg2rad;
        }
        test_value(sum, 1.0, 0.001, "PSF integration for "+eng.print());
    }

    // Return
    return;
}
Ejemplo n.º 3
0
/***********************************************************************//**
 * @brief Test CTA npsf computation
 ***************************************************************************/
void TestGCTAResponse::test_response_npsf(void)
{
    // Setup CTA response
    GCTAResponse rsp;
    rsp.caldb(cta_caldb);
    rsp.load(cta_irf);

    // Setup npsf computation
    GSkyDir      srcDir;
    GEnergy      srcEng;
    GTime        srcTime;
    GCTAPointing pnt;
    GCTARoi      roi;
    GCTAInstDir  instDir;
    instDir.radec_deg(0.0, 0.0);
    roi.centre(instDir);
    roi.radius(2.0);
    srcEng.TeV(0.1);

    // Test PSF centred on ROI
    srcDir.radec_deg(0.0, 0.0);
    double npsf = rsp.npsf(srcDir, srcEng.log10TeV(), srcTime, pnt, roi);
    test_value(npsf, 1.0, 1.0e-3, "PSF(0,0) integration");

    // Test PSF offset but inside ROI
    srcDir.radec_deg(1.0, 1.0);
    npsf = rsp.npsf(srcDir, srcEng.log10TeV(), srcTime, pnt, roi);
    test_value(npsf, 1.0, 1.0e-3, "PSF(1,1) integration");

    // Test PSF outside and overlapping ROI
    srcDir.radec_deg(0.0, 2.0);
    npsf = rsp.npsf(srcDir, srcEng.log10TeV(), srcTime, pnt, roi);
    test_value(npsf, 0.492373, 1.0e-3, "PSF(0,2) integration");

    // Test PSF outside ROI
    srcDir.radec_deg(2.0, 2.0);
    npsf = rsp.npsf(srcDir, srcEng.log10TeV(), srcTime, pnt, roi);
    test_value(npsf, 0.0, 1.0e-3, "PSF(2,2) integration");

    // Return
    return;
}
Ejemplo n.º 4
0
/***********************************************************************//**
 * @brief Test CTA Aeff computation
 ***************************************************************************/
void TestGCTAResponse::test_response_aeff(void)
{
    // Load response
    GCTAResponse rsp;
    rsp.caldb(cta_caldb);
    rsp.load(cta_irf);

    // Sum over effective area for control
    GEnergy      eng;
    double sum = 0.0;
    double ref = 154124059000.00006; //!< Adjust to actual value
    for (int i = 0; i < 30; ++i) {
        eng.TeV(pow(10.0, -1.7 + 0.1*double(i)));
        double aeff = rsp.aeff(0.0, 0.0, 0.0, 0.0, eng.log10TeV());
        //std::cout << eng << " " << eng.log10TeV() << " " << aeff << std::endl;
        sum += aeff;
    }
    test_value(sum, ref, 0.1, "Effective area verification");

    // Return
    return;
}
Ejemplo n.º 5
0
/***********************************************************************//**
 * @brief Test CTA IRF computation for diffuse source model
 *
 * Tests the IRF computation for the diffuse source model. This is done
 * by calling the GCTAObservation::model method which in turn calls the
 * GCTAResponse::irf_diffuse method. The test is done for a small counts
 * map to keep the test executing reasonably fast.
 ***************************************************************************/
void TestGCTAResponse::test_response_irf_diffuse(void)
{
    // Set reference value
    double ref = 13803.800313356;

    // Set parameters
    double src_ra  = 201.3651;
    double src_dec = -43.0191;
    int    nebins  = 5;

    // Setup pointing on Cen A
    GSkyDir skyDir;
    skyDir.radec_deg(src_ra, src_dec);
    GCTAPointing pnt;
    pnt.dir(skyDir);

    // Setup skymap (10 energy layers)
    GSkymap map("CAR", "CEL", src_ra, src_dec, 0.5, 0.5, 10, 10, nebins);

    // Setup time interval
    GGti  gti;
    GTime tstart(0.0);
    GTime tstop(1800.0);
    gti.append(tstart, tstop);

    // Setup energy boundaries
    GEbounds ebounds;
    GEnergy  emin;
    GEnergy  emax;
    emin.TeV(0.1);
    emax.TeV(100.0);
    ebounds.setlog(emin, emax, nebins);

    // Setup event cube centered on Cen A
    GCTAEventCube cube(map, ebounds, gti);

    // Setup dummy CTA observation
    GCTAObservation obs;
    obs.ontime(1800.0);
    obs.livetime(1600.0);
    obs.deadc(1600.0/1800.0);
    obs.response(cta_irf, cta_caldb);
    obs.events(&cube);
    obs.pointing(pnt);

    // Load model for IRF computation
    GModels models(cta_rsp_xml);

    // Reset sum
    double sum = 0.0;

    // Iterate over all bins in event cube
    for (int i = 0; i < obs.events()->size(); ++i) {

        // Get event pointer
        const GEventBin* bin = (*(static_cast<const GEventCube*>(obs.events())))[i];

        // Get model and add to sum
        double model = obs.model(models, *bin, NULL) * bin->size();
        sum += model;

    }

    // Test sum
    test_value(sum, ref, 1.0e-5, "Diffuse IRF computation");

    // Return
    return;
}
Ejemplo n.º 6
0
/***********************************************************************//**
 * @brief Set empty CTA event list
 *
 * @param[in] obs CTA observation.
 *
 * Attaches an empty event list to CTA observation. The method also sets the
 * pointing direction using the m_ra and m_dec members, the ROI based on
 * m_ra, m_dec and m_rad, a single GTI based on m_tmin and m_tmax, and a
 * single energy boundary based on m_emin and m_emax. The method furthermore
 * sets the ontime, livetime and deadtime correction factor.
 ***************************************************************************/
void ctobssim::set_list(GCTAObservation* obs)
{
    // Continue only if observation is valid
    if (obs != NULL) {

        // Get CTA observation parameters
        m_ra    = (*this)["ra"].real();
        m_dec   = (*this)["dec"].real();
        m_rad   = (*this)["rad"].real();
        m_tmin  = (*this)["tmin"].real();
        m_tmax  = (*this)["tmax"].real();
        m_emin  = (*this)["emin"].real();
        m_emax  = (*this)["emax"].real();
        m_deadc = (*this)["deadc"].real();

        // Allocate CTA event list
        GCTAEventList events;

        // Set pointing direction
        GCTAPointing pnt;
        GSkyDir      skydir;
        skydir.radec_deg(m_ra, m_dec);
        pnt.dir(skydir);

        // Set ROI
        GCTAInstDir instdir(skydir);
        GCTARoi     roi(instdir, m_rad);

        // Set GTI
        GGti  gti(m_cta_ref);
        GTime tstart;
        GTime tstop;
        tstart.set(m_tmin, m_cta_ref);
        tstop.set(m_tmax, m_cta_ref);
        gti.append(tstart, tstop);

        // Set energy boundaries
        GEbounds ebounds;
        GEnergy  emin;
        GEnergy  emax;
        emin.TeV(m_emin);
        emax.TeV(m_emax);
        ebounds.append(emin, emax);

        // Set CTA event list attributes
        events.roi(roi);
        events.gti(gti);
        events.ebounds(ebounds);

        // Attach event list to CTA observation
        obs->events(events);

        // Set observation ontime, livetime and deadtime correction factor
        obs->ontime(gti.ontime());
        obs->livetime(gti.ontime()*m_deadc);
        obs->deadc(m_deadc);

    } // endif: oberservation was valid

    // Return
    return;
}
Ejemplo n.º 7
0
/***********************************************************************//**
 * @brief Bin events into a counts map
 *
 * @param[in] obs CTA observation.
 *
 * @exception GException::no_list
 *            No event list found in observation.
 * @exception GCTAException::no_pointing
 *            No valid CTA pointing found.
 *
 * This method bins the events found in a CTA events list into a counts map
 * and replaces the event list by the counts map in the observation. The
 * energy boundaries of the counts map are also stored in the observation's
 * energy boundary member.
 *
 * If the reference values for the map centre (m_xref, m_yref) are 9999.0,
 * the pointing direction of the observation is taken as the map centre.
 * Otherwise, the specified reference value is used.
 ***************************************************************************/
void ctbin::bin_events(GCTAObservation* obs)
{
    // Continue only if observation pointer is valid
    if (obs != NULL) {

        // Make sure that the observation holds a CTA event list. If this
        // is not the case then throw an exception.
        if (dynamic_cast<const GCTAEventList*>(obs->events()) == NULL) {
            throw GException::no_list(G_BIN_EVENTS);
        }

        // Setup energy range covered by data
        GEnergy  emin;
        GEnergy  emax;
        GEbounds ebds;
        emin.TeV(m_emin);
        emax.TeV(m_emax);
        ebds.setlog(emin, emax, m_enumbins);

        // Get Good Time intervals
        GGti gti = obs->events()->gti();
        
        // Get map centre
        double xref;
        double yref;
        if (m_xref != 9999.0 && m_yref != 9999.0) {
            xref = m_xref;
            yref = m_yref;
        }
        else {
            
            // Get pointer on CTA pointing
            const GCTAPointing *pnt = obs->pointing();
            if (pnt == NULL) {
                throw GCTAException::no_pointing(G_BIN_EVENTS);
            }
            
            // Set reference point to pointing
            if (toupper(m_coordsys) == "GAL") {
                xref = pnt->dir().l_deg();
                yref = pnt->dir().b_deg();
            }
            else {
                xref = pnt->dir().ra_deg();
                yref = pnt->dir().dec_deg();
            }

        } // endelse: map centre set to pointing

        // Create skymap
        GSkymap map = GSkymap(m_proj, m_coordsys,
                              xref, yref, m_binsz, m_binsz,
                              m_nxpix, m_nypix, m_enumbins);

        // Initialise binning statistics
        int num_outside_map  = 0;
        int num_outside_ebds = 0;
        int num_in_map       = 0;

        // Fill sky map
        GCTAEventList* events = static_cast<GCTAEventList*>(const_cast<GEvents*>(obs->events()));
        for (GCTAEventList::iterator event = events->begin(); event != events->end(); ++event) {

            // Determine sky pixel
            GCTAInstDir* inst  = (GCTAInstDir*)&(event->dir());
            GSkyDir      dir   = inst->dir();
            GSkyPixel    pixel = map.dir2xy(dir);

            // Skip if pixel is out of range
            if (pixel.x() < -0.5 || pixel.x() > (m_nxpix-0.5) ||
                pixel.y() < -0.5 || pixel.y() > (m_nypix-0.5)) {
                num_outside_map++;
                continue;
            }

            // Determine energy bin. Skip if we are outside the energy range
            int index = ebds.index(event->energy());
            if (index == -1) {
                num_outside_ebds++;
                continue;
            }

            // Fill event in skymap
            map(pixel, index) += 1.0;
            num_in_map++;

        } // endfor: looped over all events

        // Log binning results
        if (logTerse()) {
            log << std::endl;
            log.header1("Binning");
            log << parformat("Events in list");
            log << obs->events()->size() << std::endl;
            log << parformat("Events in map");
            log << num_in_map << std::endl;
            log << parformat("Events outside map area");
            log << num_outside_map << std::endl;
            log << parformat("Events outside energy bins");
            log << num_outside_ebds << std::endl;
        }

        // Log map
        if (logTerse()) {
            log << std::endl;
            log.header1("Counts map");
            log << map << std::endl;
        }

        // Create events cube from sky map
        GCTAEventCube cube(map, ebds, gti);

        // Replace event list by event cube in observation
        obs->events(&cube);

    } // endif: observation was valid

    // Return
    return;
}
Ejemplo n.º 8
0
/***********************************************************************//**
 * @brief Select events
 *
 * @param[in] obs CTA observation.
 * @param[in] filename File name.
 *
 * Select events from a FITS file by making use of the selection possibility
 * of the cfitsio library on loading a file. A selection string is created
 * from the specified criteria that is appended to the filename so that
 * cfitsio will automatically filter the event data. This selection string
 * is then applied when opening the FITS file. The opened FITS file is then
 * saved into a temporary file which is the loaded into the actual CTA
 * observation, overwriting the old CTA observation. The ROI, GTI and EBounds
 * of the CTA event list are then set accordingly to the specified selection.
 * Finally, the temporary file created during this process is removed.
 *
 * Good Time Intervals of the observation will be limited to the time
 * interval [m_tmin, m_tmax]. If m_tmin=m_tmax=0, no time selection is
 * performed.
 *
 * @todo Use INDEF instead of 0.0 for pointing as RA/DEC selection
 ***************************************************************************/
void ctselect::select_events(GCTAObservation* obs, const std::string& filename)
{
    // Allocate selection string
    std::string selection;
    char        cmin[80];
    char        cmax[80];
    char        cra[80];
    char        cdec[80];
    char        crad[80];

    // Set requested selections
    bool select_time = (m_tmin != 0.0 || m_tmax != 0.0);

    // Set RA/DEC selection
    double ra  = m_ra;
    double dec = m_dec;
    if (m_usepnt) {
        const GCTAPointing *pnt = obs->pointing();
        ra = pnt->dir().ra_deg();
        dec = pnt->dir().dec_deg();
    }

    // Set time selection interval. We make sure here that the time selection
    // interval cannot be wider than the GTIs covering the data. This is done
    // using GGti's reduce() method.
    if (select_time) {

        // Reduce GTIs to specified time interval. The complicated cast is
        // necessary here because the gti() method is declared const, so
        // we're not officially allowed to modify the GTIs.
        ((GGti*)(&obs->events()->gti()))->reduce(m_timemin, m_timemax);

    } // endif: time selection was required

    // Save GTI for later usage
    GGti gti = obs->events()->gti();

    // Make time selection
    if (select_time) {
    
        // Extract effective time interval in CTA reference time. We need
        // this reference for filtering.
        double tmin = gti.tstart().convert(m_cta_ref);
        double tmax = gti.tstop().convert(m_cta_ref);

        // Format time with sufficient accuracy and add to selection string
        sprintf(cmin, "%.8f", tmin);
        sprintf(cmax, "%.8f", tmax);
        selection = "TIME >= "+std::string(cmin)+" && TIME <= "+std::string(cmax);
        if (logTerse()) {
            log << parformat("Time range");
            log << tmin << " - " << tmax << " s" << std::endl;
        }
        if (selection.length() > 0) {
            selection += " && ";
        }
    }

    // Make energy selection
    sprintf(cmin, "%.8f", m_emin);
    sprintf(cmax, "%.8f", m_emax);
    selection += "ENERGY >= "+std::string(cmin)+" && ENERGY <= "+std::string(cmax);
    if (logTerse()) {
        log << parformat("Energy range");
        log << m_emin << " - " << m_emax << " TeV" << std::endl;
    }
    if (selection.length() > 0) {
        selection += " && ";
    }

    // Make ROI selection
    sprintf(cra,  "%.6f", ra);
    sprintf(cdec, "%.6f", dec);
    sprintf(crad, "%.6f", m_rad);
    selection += "ANGSEP("+std::string(cra)+"," +
                 std::string(cdec)+",RA,DEC) <= " +
                 std::string(crad);
    if (logTerse()) {
        log << parformat("Acceptance cone centre");
        log << "RA=" << ra << ", DEC=" << dec << " deg" << std::endl;
        log << parformat("Acceptance cone radius");
        log << m_rad << " deg" << std::endl;
    }
    if (logTerse()) {
        log << parformat("cfitsio selection");
        log << selection << std::endl;
    }

    // Add additional expression
    if (strip_whitespace(m_expr).length() > 0) {
        if (selection.length() > 0) {
            selection += " && ";
        }
        selection += "("+strip_whitespace(m_expr)+")";
    }

    // Build input filename including selection expression
    std::string expression = filename;
    if (selection.length() > 0)
        expression += "[EVENTS]["+selection+"]";
    if (logTerse()) {
        log << parformat("FITS filename");
        log << expression << std::endl;
    }

    // Open FITS file
    GFits file(expression);

    // Log selected FITS file
    if (logExplicit()) {
        log << std::endl;
        log.header1("FITS file content after selection");
        log << file << std::endl;
    }

    // Check if we have an EVENTS HDU
    if (!file.hashdu("EVENTS")) {
        std::string message = "No \"EVENTS\" extension found in FITS file "+
                              expression+".";
        throw GException::app_error(G_SELECT_EVENTS, message);
    }

    // Determine number of events in EVENTS HDU
    int nevents = file.table("EVENTS")->nrows();

    // If the selected event list is empty then append an empty event list
    // to the observation. Otherwise load the data from the temporary file.
    if (nevents < 1) {

        // Create empty event list
        GCTAEventList eventlist;

        // Append list to observation
        obs->events(&eventlist);

    }
    else {

        // Get temporary file name
        std::string tmpname = std::tmpnam(NULL);

        // Save FITS file to temporary file
        file.saveto(tmpname, true);

        // Load observation from temporary file
        obs->load_unbinned(tmpname);

        // Remove temporary file
        std::remove(tmpname.c_str());

    }

    // Get CTA event list pointer
    GCTAEventList* list =
        static_cast<GCTAEventList*>(const_cast<GEvents*>(obs->events()));

    // Set ROI
    GCTARoi     roi;
    GCTAInstDir instdir;
    instdir.radec_deg(ra, dec);
    roi.centre(instdir);
    roi.radius(m_rad);
    list->roi(roi);

    // Set GTI
    list->gti(gti);

    // Set energy boundaries
    GEbounds ebounds;
    GEnergy  emin;
    GEnergy  emax;
    emin.TeV(m_emin);
    emax.TeV(m_emax);
    ebounds.append(emin, emax);
    list->ebounds(ebounds);

    // Recompute ontime and livetime.
    GTime meantime = 0.5 * (gti.tstart() + gti.tstop());
    obs->ontime(gti.ontime());
    obs->livetime(gti.ontime() * obs->deadc(meantime));

    // Return
    return;
}