t=0.01;
tx = 0:t:2*pi;
xy=sin(tx);
figure(1);

dt=1/(length(tx)-1);
T=0:dt:1;
plot (T,xy);


%Mittelwert,amplitude bilden
average=sum(xy)/length(xy);
amlitude=(max(xy)-min(xy))/2;

xy_av= xy- average;

%Harmonischeauswaehlen:
N=10;
p=N*1;

fft_this(xy_av,N,p);