clc;clear;%建立符号变量a(发展系数)和b(灰作用量)
%原始数列 A
A = [188.136,198.305,173.051,228.814,215.983,249.153,279.661,284.746,268.746,315.254,345.763,399.186,391.525,416.949,452.542,452.542,493.22,550.22,544.068,574.576,605.085,666.102,711.864,867.627,823.729,874.576,910.169,935.593,986.441,1042.37,1103.39,1330.49,1205.08,1250.85,1301.69,1347.46,1383.05,1418.64,1418.64];
n = length(A);
%对原始数列 A 做累加得到数列 B
B = cumsum(A);
%对数列 B 做紧邻均值生成
for i = 2:n
C(i) = (B(i) + B(i - 1))/2;
end
C(1) = [];
%构造数据矩阵
B = [-C;ones(1,n-1)];
Y = A; Y(1) = []; Y = Y';
%使用最小二乘法计算参数 a(发展系数)和b(灰作用量)
c = inv(B*B')*B*Y;
c = c';
a = c(1); b = c(2);
%预测后续数据
F = []; F(1) = A(1);
for i = 2:(n+39)
F(i) = (A(1)-b/a)/exp(a*(i-1))+ b/a;
end
%对数列 F 累减还原,得到预测出的数据
G = []; G(1) = A(1);
for i = 2:(n+39)
G(i) = F(i) - F(i-1); %得到预测出来的数据
end
disp('预测数据为:');
G
%模型检验
H = G(1:39);
%计算残差序列
epsilon = A - H;
%法一:相对残差Q检验
%计算相对误差序列
delta = abs(epsilon./A);
%计算相对误差Q
disp('相对残差Q检验:')
Q = mean(delta)
%法二:方差比C检验
disp('方差比C检验:')
C = std(epsilon, 1)/std(A, 1)
%法三:小误差概率P检验
S1 = std(A, 1);
tmp = find(abs(epsilon - mean(epsilon))< 0.6745 * S1);
disp('小误差概率P检验:')
P = length(tmp)/(n+10)
%绘制曲线图
t1 = (1:1:39);
t2 = (1:1:78);
plot(t1, A, 'ro'); hold on;
plot(t2, G, 'g-');
xlabel('时间'); ylabel('累计位移量/mm');
legend('ZG34实测累计位移量','ZG34预测累计位移量');
grid on;