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 f% Q6 R/ K/ g' ]
T=input('T=');%从键盘输入从最后一个历史数据算起的第T时点# r: r4 x# S. W- L0 y* E( ^' d
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);
% R* g' @0 a/ F' S' x- T
Hatx00=zeros(1,length(x0));Hatx1=zeros(1,length(x0)+T);" f' U' e5 g/ [5 c' K
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& n/ P) }! W; E) f$ r1 {$ Y2 A
x1(i)=x1(i)+x0(j);
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end
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end* t3 }( y# E3 P8 o# x1 z
for i=1:length(x0)-1) [6 q; |3 B% m( b: P
B(i,1)=(-1/2)*(x1(i)+x1(i+1));/ f/ \( _) R2 ?) W+ r' W
B(i,2)=1;; R8 [- p% q* m+ F9 Z" Q0 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
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for k=1:length(x0)+T: K, _( f2 v( ^; q2 `6 J. @, y
Hatx1(k)=(x0(1)-HatA(2)/HatA(1))*exp(-HatA(1)*(k-1))+HatA(2)/HatA(1);$ }9 q1 l# w9 }+ a) t$ C6 K7 x
end
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Hatx0(1)=Hatx1(1);
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for k=2:length(x0)+T
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Hatx0(k)=Hatx1(k)-Hatx1(k-1);%累计还原得到历史数据的模拟值( l5 O( q6 [) O+ Y. q
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);% o& o, ?, c- l ?
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8 C. z, O3 N0 w. v/ a# x
c=std(epsilon)/std(x0);p=0;9 r7 z' L8 \4 w& u. E- S" Q
for i=1:length(x0)* m' \ r; u9 z/ d* |4 a
if abs(epsilon(i)-mean(epsilon))<0.6745*std(x0)& K8 u. s/ E0 ^/ L3 k8 `3 g
p=p+1;
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end
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end
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p=p/length(x0)
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if p>0.95 & c<0.35
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disp('The model is good,and the forecast is:'),! k" b6 V9 @$ v a# C
disp(Hatx0(length(x0)+T))
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elseif p>0.85 & c<0.51 M0 z* l* b5 c1 U
disp('The model is eligibility,and the forecast is:'),) g. Z5 }) Z! F5 ]8 D# v
disp(Hatx0(length(x0)+T))6 M" G/ M6 l/ o K, n( R" D
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))5 H+ L Y7 s' A9 |- I
else p<=0.7 & c>0.657 M2 n4 ?! I/ n( ~' Y4 [$ p1 e
disp('The model is bad and try again')+ ]# Q5 S! y8 J! l7 P8 L9 S
end* t* a" M; t7 J; @/ O4 y+ X( K4 h
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2 r% t$ d+ K5 e1 X+ T6 p* J
text(2,x0(2),'History data: real line')
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text(length(x0)/2,Hatx00(length(x0))/2,'Simulation data:broken line')9 Q: y) q8 B' N5 d
end

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T=[2 3 4 5 3 2]' Y( h2 z) l" W
Warning: Input arguments must be scalar.5 _* \- C5 A7 W1 v4 s
> In fungry1 at 40 L0 n9 B5 p' \: ^
Warning: Input arguments must be scalar.
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> In fungry1 at 56 l/ `- c$ p( ^. r
Warning: Matrix is singular to working precision.( ~( j6 R5 I( b4 |3 M
> In fungry1 at 17! P, x4 k9 _/ P
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HatA =! X' k. F* N4 ]7 h! F' ]1 X" H1 Q
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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.4 [ I* b2 c+ K# W/ U" V) W
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Error in ==> fungry1 at 54
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text(2,x0(2),'History data: real line')
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