njit-etd2003-081 - New Jersey Institute of Technology

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x = decimate(rawdata,10);
N = length(x);
%*sf = 1000;
%*N = 500;
%%T = 1/400;
ws = T*sf;
%*nfft = 256;
%*wave = 'mexh';
Tool Box v 2.0
% decimate data array
% number of samples
% sampling frequency
% number of samples
% window size in seconds (1/400 = 0.025 sec)
% window size in samples
% fft size in spectrogram command. Must be larger than
% window size in samples
% the wavelet to use (see wavelets table in Matlab Wavelet
t = ( (1:(N)) )* (1/s0;
f= ( (0:(N-1))/N) * sf;
index = 1:N;
% times
% frequencies
% first construct the time domain and frequency domain plots
fx = abs(fft(x));
% spectrumlD.m
% function [Pyy,f]=rspec(x,Fs)
fftsize=length(x);
% put alternative fft method here
x=x-mean(x);
fftx=fft(x,fftsize);
Pyy=fftx.*conj(fftx)/fftsize;
% f=sf*(0:(fftsize/2-1))/fftsize;
f=sPc(0:(fftsize-1))/fftsize;
clear fftx
P=PYY;
figure;
subplot(2,1,1)
plot(t,x);
% axis([0 20 -2 5]);
grid on;
xlabel('Time (sec)');
ylabel('Amplitude');
title(['Raw data in time domain of',eval('filename')]);
subplot(2,1,2);
% plot(f(400:800),p(400:800)/max(p),'r');
plot(f(1:200),p(1:200)/max(p),er');