spectrogram {RHRV}R Documentation

Calculates the spectrogram of a signal

Description

Calculates the spectrogram of the heart rate signal after filtering and interpolation in a window of a certain size

Usage

spectrogram(signal, size, shift, fsamp = 4)

Arguments

signal the heart rate signal after filtering and interpolation
size size of window (seconds)
shift displacement of window (seconds)
fsamp sampling frequency

Value

A matrix with the module of the FFT of the signal

Author(s)

M. Lado, A. Mendez, D. Olivieri, L. Rodriguez, X. Vila

References

L. Rodriguez-Linares, X. Vila, A. Mendez, M. Lado, D. Olivieri, "RHRV: An R-based software package for heart rate variability analysis of ECG recordings," 3rd Iberian Conference in Systems and Information Technologies (CISTI 2008), 21-23 June 2008.

Examples

  ## Signal Creation
  l=1000;
  hamming=0.54-0.46*cos(2*pi*(0:(l-1))/(l-1))
  x=seq(length=l,from=0,by=.25)
  s1=sin(x*2.0*pi*0.025)*hamming
  s2=sin(x*2.0*pi*0.1)*hamming
  s3=sin(x*2.0*pi*0.3)*hamming
  s4=s1+s2+s3
  s=c(s1,s2,s3,s4)
  s=array(c(1:(4*l),s),dim=c(4*l,2))
  ## Calculating Spectrogram
  specgr=spectrogram(s,120,5,4)

[Package RHRV version 1.0 Index]