Gamma_Analysis.py 文件源码

def peak_finder(spectrum, energy):
    '''
    PEAK_FINDER will search for peaks within a certain range determined by the
    Energy given. It takes a Spectra file and an Energy value as input. The
    energy range to look in is given by the Full-Width-Half-Maximum (FWHM).
    If more than one peak is found in the given range, the peak with the
    highest amount of counts will be used.
    '''
    e0 = spectrum.energy_cal[0]
    eslope = spectrum.energy_cal[1]
    energy_axis = e0 + eslope*spectrum.channel

    peak_energy = []
    # rough estimate of fwhm.
    fwhm = 0.05*energy**0.5
    fwhm_range = 1

    # peak search area
    start_region = np.flatnonzero(energy_axis > energy - fwhm_range * fwhm)[0]
    end_region = np.flatnonzero(energy_axis > energy + fwhm_range * fwhm)[0]
    y = spectrum.data[start_region:end_region]
    indexes = peakutils.indexes(y, thres=0.5, min_dist=4)
    tallest_peak = []
    if indexes.size == 0:
        peak_energy.append(int((end_region - start_region) / 2) + start_region)
    else:
        for i in range(indexes.size):
            spot = spectrum.data[indexes[i]+start_region]
            tallest_peak.append(spot)
        indexes = indexes[np.argmax(tallest_peak)]
        peak_energy.append(int(indexes+start_region))
    peak_energy = float(energy_axis[peak_energy])
    return(peak_energy)