Comparison with Fourier Power Spectrum. Power spectrum of the raw pattern extracted by SVD for Chr1p (see Fig. 5B) (dotted) and that of the de-noised spectrum (see Fig. 5D) (line). Note that the de-noising procedure effectively removes the noise at high frequencies but preserves the large structure in the signal (< 10 Hz). The dip in the de-noised spectrum at > 103 Hz is due to the zeroing of the highest frequency content in the WT corresponding to the single probes expression.