spectrum.py 文件源码

def peaks(spectra,frequency,number=3,thresh=0.01):
        """ Return the peaks from the Fourier transform
            Variables:
            number:     integer. number of peaks to print.
            thresh:     float. Threshhold intensity for printing.

            Returns: Energy (eV), Intensity (depends on type of spectra)
        """

        from scipy.signal import argrelextrema as pks
        # find all peak indices [idx], and remove those below thresh [jdx]
        idx = pks(np.abs(spectra),np.greater,order=3)
        jdx = np.where((np.abs(spectra[idx]) >= thresh))
        kdx = idx[0][jdx[0]] # indices of peaks matching criteria
        if number > len(kdx):
            number = len(kdx)
        print("First "+str(number)+" peaks (eV) found: ")
        for i in xrange(number):
            print("{0:.4f}".format(frequency[kdx][i]*27.2114),
                  "{0:.4f}".format(spectra[kdx][i]))