Resampling with the Berger algorithm [HRV,RRI] = berger(RRI, Fs) [HRV,RRI] = berger(ONSET, Fs) [HRV,RRI] = berger(HDR, Fs) RRI R-to-R interval ONSET onset time QRS-complex Fs target sampling rate HDR header struct as defined by SOPEN, SLOAD. HDR.EVENT must contain the QRS events HRV heart rate variability sampled with Fs RRI R-to-R interval sampled with Fs Reference(s):  Berger RD, Akselrod S, Gordon D, Cohen RJ. An efficient algorithm for spectral analysis of heart rate variability. IEEE Trans Biomed Eng. 1986 Sep;33(9):900-4.