t = (1900:10:2000)';
p = [75.995 91.972 105.711 123.203 131.669 ... 150.697 179.323 203.212 226.505 249.633 281.422]';plot(t,p,'bo');axis([1900 2020 0 400]);title('1900-2000 数据');ylabel('百万');n = length(t);s = (t-1950)/50;A = zeros(n);A(:,end) = 1;for j = n-1:-1:1 A(:,j) = s .* A(:,j+1);endc = A(:,n-3:n)\pv = (1900:2020)';x = (v-1950)/50;w = (2010-1950)/50;y = polyval(c,x);z = polyval(c,w);hold onplot(v,y,'k-');plot(2010,z,'ks');text(2010,z+15,num2str(z));hold off复制代码
文章评论(0条评论)
登录后参与讨论