cdgood.m

signal and system answer

clear
load cdgood
nihex3=zeros(111,8);
nihey3=ones(111,8)*1000;
for i=1:106
    k=1;
    for j=1:45
        if cdfen3nihe(i,j)~=1000&xiabiao3(i,j)~=0
            nihex3(i,k)=xiabiao3(i,j);
            nihey3(i,k)=cdfen3nihe(i,j);
            k=k+1;
        end
    end
end
cdfen3nihe=0.2*cdfen3nihe;
nihey3=0.2*nihey3;
l=ones(1,106);
for i=1:106
    k=1;
    while nihex3(i,k)~=0
       k=k+1;
    end
    k=k-1;
    x3=nihex3(i,1:k);
    while nihey3(i,l(i))~=1000*0.2
       l(i)=l(i)+1;
    end
    l(i)=l(i)-1;
    y3=nihey3(i,1:l(i));
   
    pcd3(i,:)=polyfit(x3,y3,2);
end
for i=1:106
    for j=1:45
        if cdfen3nihe(i,j)==1000*0.2;
            cdfen3nihe(i,j)=polyval(pcd3(i,:),j);
        else
            l(i)=l(i)-1;
        end
          if cdfen3nihe(i,j)<=0|l(i)==0
            cdfen3nihe(i,j)=0;
        end
    end
end
bilv3cd=zeros(106,45);
for j=1:106
    k=1;
    while k<=45&cdfen3nihe(j,k)~=0
        k=k+1;
    end
    k=k-1;
    for i=1:k
        if i==1
            bilv3cd(j,1)=(-3*cdfen3nihe(j,1)+4*cdfen3nihe(j,2)-cdfen3nihe(j,3))/2;
        elseif i~=k
            bilv3cd(j,i)=(cdfen3nihe(j,i+1)-cdfen3nihe(j,i-1))/2;
        elseif k>2
            bilv3cd(j,k)=(cdfen3nihe(j,k-2)-4*cdfen3nihe(j,k-1)+3*cdfen3nihe(j,k))/2;
        end
    end
end
numx3=zeros(1,45);numy3=zeros(1,45);
for i=1:106
    for j=1:45
        if bilv3cd(i,j)~=0
            numx3(j)=numx3(j)+1;
        end
        if cdfen3nihe(i,j)~=0
            numy3(j)=numy3(j)+1;
        end
    end
end
sc=sum(cdfen3nihe);
cdfen3nihemean=sc(1:44)./numy3(1:44);
month=1:44;
figure
plot(month,cdfen3nihemean,'r.')