def main():
    """
    NAME
        dmag_magic2.py

    DESCRIPTION
       plots intensity decay curves for demagnetization experiments

    SYNTAX
        dmag_magic -h [command line options]

    INPUT
       takes magic formatted magic_measurements.txt files

    OPTIONS
        -h prints help message and quits
        -f FILE: specify input file, default is: magic_measurements.txt
        -obj OBJ: specify  object  [loc, sit, sam, spc] for plot, default is by location
        -LT [AF,T,M]: specify lab treatment type, default AF
        -XLP [PI]: exclude specific  lab protocols (for example, method codes like LP-PI)
        -N do not normalize by NRM magnetization
        -sav save plots silently and quit
        -fmt [svg,jpg,png,pdf] set figure format [default is svg]
    NOTE
        loc: location (study); sit: site; sam: sample; spc: specimen
    """
    FIG = {}  # plot dictionary
    FIG['demag'] = 1  # demag is figure 1
    in_file, plot_key, LT = 'magic_measurements.txt', 'er_location_name', "LT-AF-Z"
    XLP = ""
    norm = 1
    LT = 'LT-AF-Z'
    units, dmag_key = 'T', 'treatment_ac_field'
    plot = 0
    fmt = 'svg'
    if len(sys.argv) > 1:
        if '-h' in sys.argv:
            print(main.__doc__)
            sys.exit()
        if '-N' in sys.argv:
            norm = 0
        if '-sav' in sys.argv:
            plot = 1
        if '-f' in sys.argv:
            ind = sys.argv.index("-f")
            in_file = sys.argv[ind+1]
        if '-fmt' in sys.argv:
            ind = sys.argv.index("-fmt")
            fmt = sys.argv[ind+1]
        if '-obj' in sys.argv:
            ind = sys.argv.index('-obj')
            plot_by = sys.argv[ind+1]
            if plot_by == 'sit':
                plot_key = 'er_site_name'
            if plot_by == 'sam':
                plot_key = 'er_sample_name'
            if plot_by == 'spc':
                plot_key = 'er_specimen_name'
        if '-XLP' in sys.argv:
            ind = sys.argv.index("-XLP")
            XLP = sys.argv[ind+1]  # get lab protocol for excluding
        if '-LT' in sys.argv:
            ind = sys.argv.index("-LT")
            LT = 'LT-'+sys.argv[ind+1]+'-Z'  # get lab treatment for plotting
            if LT == 'LT-T-Z':
                units, dmag_key = 'K', 'treatment_temp'
            elif LT == 'LT-AF-Z':
                units, dmag_key = 'T', 'treatment_ac_field'
            elif LT == 'LT-M-Z':
                units, dmag_key = 'J', 'treatment_mw_energy'
            else:
                units = 'U'
    data, file_type = pmag.magic_read(in_file)
    sids = pmag.get_specs(data)
    pmagplotlib.plot_init(FIG['demag'], 5, 5)
    print(len(data), ' records read from ', in_file)
    #
    #
    # find desired intensity data
    #
    #
    plotlist, intlist = [], ['measurement_magnitude', 'measurement_magn_moment',
                             'measurement_magn_volume', 'measurement_magn_mass']
    IntMeths = []
    FixData = []
    for rec in data:
        meths = []
        methcodes = rec['magic_method_codes'].split(':')
        for meth in methcodes:
            meths.append(meth.strip())
        for key in rec.keys():
            if key in intlist and rec[key] != "":
                if key not in IntMeths:
                    IntMeths.append(key)
                if rec[plot_key] not in plotlist and LT in meths:
                    plotlist.append(rec[plot_key])
                if 'measurement_flag' not in rec.keys():
                    rec['measurement_flag'] = 'g'
                FixData.append(rec)
        plotlist.sort()
    if len(IntMeths) == 0:
        print('No intensity information found')
        sys.exit()
    data = FixData
    # plot first intensity method found - normalized to initial value anyway - doesn't matter which used
    int_key = IntMeths[0]
    for plt in plotlist:
        if plot == 0:
            print(plt, 'plotting by: ', plot_key)
        # fish out all the data for this type of plot
        PLTblock = pmag.get_dictitem(data, plot_key, plt, 'T')
        # fish out all the dmag for this experiment type
        PLTblock = pmag.get_dictitem(PLTblock, 'magic_method_codes', LT, 'has')
        # get all with this intensity key non-blank
        PLTblock = pmag.get_dictitem(PLTblock, int_key, '', 'F')
        if XLP != "":
            # reject data with XLP in method_code
            PLTblock = pmag.get_dictitem(
                PLTblock, 'magic_method_codes', XLP, 'not')
        if len(PLTblock) > 2:
            title = PLTblock[0][plot_key]
            spcs = []
            for rec in PLTblock:
                if rec['er_specimen_name'] not in spcs:
                    spcs.append(rec['er_specimen_name'])
            for spc in spcs:
                # plot specimen by specimen
                SPCblock = pmag.get_dictitem(
                    PLTblock, 'er_specimen_name', spc, 'T')
                INTblock = []
                for rec in SPCblock:
                    INTblock.append([float(rec[dmag_key]), 0, 0, float(
                        rec[int_key]), 1, rec['measurement_flag']])
                if len(INTblock) > 2:
                    pmagplotlib.plot_mag(
                        FIG['demag'], INTblock, title, 0, units, norm)
            if plot == 1:
                files = {}
                for key in FIG.keys():
                    files[key] = title+'_'+LT+'.'+fmt
                pmagplotlib.save_plots(FIG, files)
                sys.exit()
            else:
                pmagplotlib.draw_figs(FIG)
                ans = input(
                    " S[a]ve to save plot, [q]uit,  Return to continue:  ")
                if ans == 'q':
                    sys.exit()
                if ans == "a":
                    files = {}
                    for key in FIG.keys():
                        files[key] = title+'_'+LT+'.'+fmt
                    pmagplotlib.save_plots(FIG, files)
            pmagplotlib.clearFIG(FIG['demag'])
NAME
        dmag_magic2.py

    DESCRIPTION
       plots intensity decay curves for demagnetization experiments

    SYNTAX
        dmag_magic -h [command line options]

    INPUT
       takes magic formatted magic_measurements.txt files

    OPTIONS
        -h prints help message and quits
        -f FILE: specify input file, default is: magic_measurements.txt
        -obj OBJ: specify  object  [loc, sit, sam, spc] for plot, default is by location
        -LT [AF,T,M]: specify lab treatment type, default AF
        -XLP [PI]: exclude specific  lab protocols (for example, method codes like LP-PI)
        -N do not normalize by NRM magnetization
        -sav save plots silently and quit
        -fmt [svg,jpg,png,pdf] set figure format [default is svg]
    NOTE
        loc: location (study); sit: site; sam: sample; spc: specimen