| GM(1,1)灰色模型的程序实现function GM1=fungry1(x0) %输入原始数据x0* m& y; C: s h5 R+ C4 ^2 u7 \* ` T=input('T=');%从键盘输入从最后一个历史数据算起的第T时点8 x+ E) W9 e- f" k: U' n4 R x1=zeros(1,length(x0));B=zeros(length(x0)-1,2);- |! U# r R* S3 j0 ]4 o4 n yn=zeros(length(x0)-1,1);Hatx0=zeros(1,length(x0)+T); Hatx00=zeros(1,length(x0));Hatx1=zeros(1,length(x0)+T); epsilon=zeros(length(x0),1);omega=zeros(length(x0),1);6 Z3 _: g( g' w, C' ~) u for i=1:length(x0); b, Y" p$ M6 o3 z3 j n- d for j=1:i$ D+ u" F% X3 Y' O$ Z! o x1(i)=x1(i)+x0(j);+ b, G4 K( u, x) t& ^5 O end end1 D* J' X5 B$ K5 E l4 L for i=1:length(x0)-1; w* `6 e+ m6 b+ b. q B(i,1)=(-1/2)*(x1(i)+x1(i+1));0 v* `& j" O7 Y. T1 v4 X B(i,2)=1;6 i9 p+ l( a. U; l5 ]3 ^ yn(i)=x0(i+1);0 F) ]7 @- @6 p4 a" K3 u4 @- W end HatA=(inv(B'*B))*B'*yn % GM(1,1)模型参数估计; w& o, W8 k6 q1 F for k=1:length(x0)+T4 V1 C( ]) Q3 u: T* H+ ]5 s Hatx1(k)=(x0(1)-HatA(2)/HatA(1))*exp(-HatA(1)*(k-1))+HatA(2)/HatA(1);( `5 A5 S" s0 d- Y- S end Hatx0(1)=Hatx1(1);9 z o% ]: l( _; S. B# U4 G3 a for k=2:length(x0)+T$ C1 b+ _. R' j$ l. n7 `6 s Hatx0(k)=Hatx1(k)-Hatx1(k-1);%累计还原得到历史数据的模拟值# ?/ R2 }* K% b9 ` end5 W8 a7 T; M% l5 f6 H$ ?3 v7 \" [; N for i=1:length(x0) %开始模型检验 epsilon(i)=x0(i)-Hatx0(i);1 h. J& R& {; Z* D7 {5 M omega(i)=(epsilon(i)/x0(i))*100;. p+ O2 |3 n' g/ F4 s( W end Z4 l0 X% K$ {7 p5 D % x0;Hatx0;epsilon;omega; %必要时去掉%得到各种数据6 B9 l1 ]* r' m4 Q6 }7 ] B c=std(epsilon)/std(x0);p=0;9 e5 \2 K' M( u+ ^; l6 j for i=1:length(x0)' z8 g& ]/ N0 l) |: q. J; D5 r if abs(epsilon(i)-mean(epsilon))<0.6745*std(x0)" {8 E; l) E. @ p=p+1; end4 N! ?9 v# E1 ^6 x7 G3 L end p=p/length(x0) if p>0.95 & c<0.35 disp('The model is good,and the forecast is:'),; U: h; u( Z6 n1 J* d7 d/ s% d, ?6 m' @ disp(Hatx0(length(x0)+T)) elseif p>0.85 & c<0.5# ^2 H2 L) |; [! O$ a7 ~0 y disp('The model is eligibility,and the forecast is:'), y* A# {1 g5 h* g" Z! f0 F" d5 h- B' U disp(Hatx0(length(x0)+T)) elseif p>0.7 & c>0.65 disp('The model is not good,and the forecast is:'), disp(Hatx0(length(x0)+T)) else p<=0.7 & c>0.65 disp('The model is bad and try again') end for i=1:length(x0)/ v% P8 Z }2 n& D Hatx00(i)=Hatx0(i); end8 B! y3 r n- H9 O z=1:length(x0); plot(z,x0,'-',z,Hatx00,':') %将原始数据和模拟值画在一个图上帮助观察; t" f, x$ o5 b text(2,x0(2),'History data: real line') text(length(x0)/2,Hatx00(length(x0))/2,'Simulation data:broken line') endT=input('T=');%从键盘输入从最后一个历史数据算起的第T时点????是指什么啊,请大哥们,大姐们教一下,我急用,请快,谢谢我的初始值x0=[1.620938526 0.07925621 0.052318818 0.041252502, y) k% s% {0 B! Z8 H 0.021800479$ E, i6 J% X3 O; @: [$ _ 0.053132975 0.089908836' B5 m N7 y* i: D5 |% v 0.1091532195 v/ ^8 g1 r! ?/ @$ t+ S 0.079331832; G! F1 j4 i+ v; c, P 0.342192598) Y9 o9 Q/ q% {, B* _# } 0.099718142 0.1351948231 o3 f, ?- P$ K) J* r6 G 0.109274037) I1 Z/ _! J# }& f 0.081520137 B C G% L2 `; f8 k) O 0.0678763558 s- e% e. k4 K) _ 0.064706843# }: `2 j2 s& G, b) y4 |0 A# l. J 0.055562197# n% T' H4 k7 @4 n4 G% S! L$ {# Z& n* z 0.050848544 ]'; |

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