for sc=1:2:35
P=power(sc,:,:);
P=squeeze(P);
P=P';
N=noise(sc,:);
%N=N';
for i=1:200
propre(i,:)=P(i,:)-N;
end
av=mean(propre,2);
u=find(av<0);
avdb=av;
avdb(u)=NaN;
figure
plot((10*log10(avdb)))
end