THE WAVELET TUTORIAL
 

							              by  Robi POLIKAR

 About The Figures 
I have generated these plots with a MATLAB code I have written
for continuous and discrete wavelet transforms. It took quite 
some time to plot the figures, and reformat them, so that they 
are Mosaic readable. Please give credits if you mail this 
tutorial to someone, or show them to someone.

I will appreciate any comments on these pages. You may e-mail 
them to me to:  rpolikar@iastate.edu

The cover figure, is the continuous wavelet transform of the 
following signal:

      


The same plot from different views are given in part 2 of the
tutorial.

The code of this signal for MATLAB is as follows:


t=0.1:0.001:0.2;
fff1=2*cos(2*pi*10*t);                    % 10 Hz. signal

t=0.2:0.001:0.3;
fff2=6*cos(2*pi*40*t)+4*cos(2*pi*10*t);   % 40 and 10 Hz signal at the
                                          same times

t=0.3:0.001:0.356;                        % 20 Hz signal
fff3=10*cos(2*pi*20*t);


fff=[fff1 fff2 fff3 fff3(51:-1:1) fff2(101:-1:1) fff1(101:-1:1)];

%Making the above signal symmetric . That is where you see the
discontinuity in the above plot.

 


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