求助，10个数据的灰色模型代码 - 数学建模社区-数学中国

function GM1=fungry1(x0) %输入原始数据x05 R$ \% d) i# J) Q9 o! s5 l/ E3 H: A' N
T=input('T=');%从键盘输入从最后一个历史数据算起的第T时点6 y* K2 L7 h4 t7 m* i
x1=zeros(1,length(x0));B=zeros(length(x0)-1,2);
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yn=zeros(length(x0)-1,1);Hatx0=zeros(1,length(x0)+T);( d+ O9 \6 v& s$ l- x. f
Hatx00=zeros(1,length(x0));Hatx1=zeros(1,length(x0)+T);
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epsilon=zeros(length(x0),1);omega=zeros(length(x0),1);. g7 {( p) a; H+ j' P3 G
for i=1:length(x0)
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for j=1:i: w2 ?+ G$ |8 y0 n( D
x1(i)=x1(i)+x0(j);
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end7 L: I; N( h3 F0 Q' V# k. r q
end0 K" U: S. _, |- I, j4 H
for i=1:length(x0)-1' C/ Y- G" i7 k5 t4 K2 z+ z
B(i,1)=(-1/2)*(x1(i)+x1(i+1));
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B(i,2)=1;0 B; D/ n' r4 {8 B" N+ B8 J. `/ `
yn(i)=x0(i+1);
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end( B1 K- b2 C7 p
HatA=(inv(B'*B))*B'*yn % GM(1,1)模型参数估计
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for k=1:length(x0)+T
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Hatx1(k)=(x0(1)-HatA(2)/HatA(1))*exp(-HatA(1)*(k-1))+HatA(2)/HatA(1);
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end
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Hatx0(1)=Hatx1(1);
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for k=2:length(x0)+T1 U& d2 v/ L C! g4 W# p
Hatx0(k)=Hatx1(k)-Hatx1(k-1);%累计还原得到历史数据的模拟值9 H- C4 | a' O' T4 M2 ^
end
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for i=1:length(x0) %开始模型检验7 O, c! V B& _; a+ E
epsilon(i)=x0(i)-Hatx0(i);
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omega(i)=(epsilon(i)/x0(i))*100;1 g) Q. k- _2 A) U
end
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% x0;Hatx0;epsilon;omega; %必要时去掉％得到各种数据
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c=std(epsilon)/std(x0);p=0;
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for i=1:length(x0)* }8 t+ T) {4 ^ R% P! h( Q
if abs(epsilon(i)-mean(epsilon))<0.6745*std(x0)
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p=p+1;
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end c+ S: k) T3 m. ~6 u% F
end, v- |& y3 a8 q3 ?) P! L
p=p/length(x0)' G; H7 V0 h r: i; t6 N' Y
if p>0.95 & c<0.35+ K/ _9 n- w) m+ u9 J
disp('The model is good,and the forecast is:'),
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disp(Hatx0(length(x0)+T))3 `: R0 |3 W, X# ]
elseif p>0.85 & c<0.5
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disp('The model is eligibility,and the forecast is:'),, g; Q4 R) S1 n) e
disp(Hatx0(length(x0)+T))1 K0 @0 ]7 a. ~- m2 K& s
elseif p>0.7 & c>0.65
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disp('The model is not good,and the forecast is:'),
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disp(Hatx0(length(x0)+T)) ?$ a/ q+ X3 R5 U/ \
else p<=0.7 & c>0.65) Z' U4 o; T+ Q2 U& g% r/ k" _
disp('The model is bad and try again')) F* E. G; f+ F* w4 `1 |- v3 W5 {
end
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for i=1:length(x0)
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Hatx00(i)=Hatx0(i);
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end
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z=1:length(x0);
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plot(z,x0,'-',z,Hatx00,':') %将原始数据和模拟值画在一个图上帮助观察- V& u' b- Z+ m# N+ o b
text(2,x0(2),'History data: real line')' N8 r3 L( v) M$ H- @
text(length(x0)/2,Hatx00(length(x0))/2,'Simulation data:broken line')
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end

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T=[2 3 4 5 3 2]
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Warning: Input arguments must be scalar.: v: G; ?% R, q% ?1 v* a( ?& B# X
> In fungry1 at 44 H$ T) }9 J: O2 D; J! c
Warning: Input arguments must be scalar.
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> In fungry1 at 5
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Warning: Matrix is singular to working precision.
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> In fungry1 at 170 c S u, c9 p' ?( w3 ~+ d, r8 f. K
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HatA =
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0
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0
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p =
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0
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ans =- m4 Z( j( X; c6 V7 E/ Y
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The model is bad and try again
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??? Index exceeds matrix dimensions.
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Error in ==> fungry1 at 544 x3 @7 j) y$ v/ t0 M$ n
text(2,x0(2),'History data: real line')
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