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x0/ p7 w! D' P4 l
T=input('T=');%从键盘输入从最后一个历史数据算起的第T时点
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x1=zeros(1,length(x0));B=zeros(length(x0)-1,2);& F( h- ~1 `; J$ c2 P7 Q
yn=zeros(length(x0)-1,1);Hatx0=zeros(1,length(x0)+T);, X6 e( K+ b: ^! ~+ s s
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);
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for i=1:length(x0)
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for j=1:i% x8 `' m8 @9 D/ X* U: W8 ^+ [
x1(i)=x1(i)+x0(j);! o5 V& }; E5 c+ F: r# m
end
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end
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for i=1:length(x0)-18 S4 i) L8 }! l, [" W7 \& }9 Z
B(i,1)=(-1/2)*(x1(i)+x1(i+1));
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B(i,2)=1;: Z B% K. V a
yn(i)=x0(i+1);
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end
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HatA=(inv(B'*B))*B'*yn % GM(1,1)模型参数估计, a$ v5 X' z4 o. S4 l4 ~
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);/ O$ d0 V5 E- b9 I
for k=2:length(x0)+T3 A% S8 j4 [- M
Hatx0(k)=Hatx1(k)-Hatx1(k-1);%累计还原得到历史数据的模拟值
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end
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for i=1:length(x0) %开始模型检验
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epsilon(i)=x0(i)-Hatx0(i);
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omega(i)=(epsilon(i)/x0(i))*100;
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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): h& L5 o% b- A0 ?+ \8 w& u3 O9 O' D! e
if abs(epsilon(i)-mean(epsilon))<0.6745*std(x0)
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p=p+1;
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end7 k9 g$ D4 A) g+ ^0 ^7 `9 i: o6 p, c, c
end
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p=p/length(x0)
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if p>0.95 & c<0.358 ^% D+ `, K6 v
disp('The model is good,and the forecast is:'),1 Z% A. S% O/ M" ]4 ^/ R$ B
disp(Hatx0(length(x0)+T))6 ]& y [/ y" E- O# K( T& f8 I
elseif p>0.85 & c<0.5
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disp('The model is eligibility,and the forecast is:'),
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disp(Hatx0(length(x0)+T))
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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))3 ~8 B2 O7 B! U7 u. w* @/ y9 c
else p<=0.7 & c>0.65& P- F& E$ _( K/ q! O
disp('The model is bad and try again')( E. ~0 C- z4 k1 i3 f2 Z) Y8 \
end9 n1 x+ I2 y7 d1 o" K; m& B: g2 g
for i=1:length(x0)
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Hatx00(i)=Hatx0(i);
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end. l3 x* N- m& _
z=1:length(x0);3 m' ?) a- ?2 b5 L7 V: Z. t1 j
plot(z,x0,'-',z,Hatx00,':') %将原始数据和模拟值画在一个图上帮助观察
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text(2,x0(2),'History data: real line')
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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]. B3 W* _+ B# p, s, P) Q/ t
Warning: Input arguments must be scalar.
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> In fungry1 at 4
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Warning: Input arguments must be scalar." A2 L" L, B+ B( p' G1 K1 P! V
> In fungry1 at 5 D% L$ q3 P8 c; Z% R
Warning: Matrix is singular to working precision. P' z3 I, F- f$ k
> In fungry1 at 17( k: ?6 |$ _/ h
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HatA =
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p =
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0
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ans =
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0
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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 549 N5 ?7 g: W) z1 x
text(2,x0(2),'History data: real line')4 I$ t( ~ x. [6 w2 j
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