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
W' ~% ]$ o, E" S7 G% p
T=input('T=');%从键盘输入从最后一个历史数据算起的第T时点0 \7 n& s/ I2 Q) ?- q
x1=zeros(1,length(x0));B=zeros(length(x0)-1,2);
5 W, b* w* p& R# [/ S: ]
yn=zeros(length(x0)-1,1);Hatx0=zeros(1,length(x0)+T);0 ^% r) M- A0 l% U0 a Y
Hatx00=zeros(1,length(x0));Hatx1=zeros(1,length(x0)+T);
! T% }& [% A4 c) `4 p
epsilon=zeros(length(x0),1);omega=zeros(length(x0),1);) Z& {( Z: G5 `4 n
for i=1:length(x0)6 y6 C0 O+ N9 h$ _: S
for j=1:i- O8 h+ P4 l1 K( U
x1(i)=x1(i)+x0(j);
# S" @7 F% {% Y' Q2 O; A0 L
end
1 a: V3 n; v/ j' o- ?
end; s' ^7 E; \1 B5 H+ ]- c% q
for i=1:length(x0)-1
. ] F4 W" \; i6 r! r" ^$ v
B(i,1)=(-1/2)*(x1(i)+x1(i+1));2 R1 G% k* ]8 e8 O
B(i,2)=1;9 }5 K! P" J# Z v/ n/ P
yn(i)=x0(i+1);( {( R" V* u8 d* w$ V
end
& k' [' v' d+ ^* G
HatA=(inv(B'*B))*B'*yn % GM(1,1)模型参数估计; F7 j1 M& s* L6 B3 t
for k=1:length(x0)+T
" ~6 c8 O5 U5 x5 e9 Z
Hatx1(k)=(x0(1)-HatA(2)/HatA(1))*exp(-HatA(1)*(k-1))+HatA(2)/HatA(1);
4 y% V0 B) Z. L$ Y
end
1 M7 ^' x- V; ^8 E+ S# [& x
Hatx0(1)=Hatx1(1);
; P% p) B; w a* G; J: F; s$ D
for k=2:length(x0)+T
7 l! C# P$ w& {7 X& N0 d# G
Hatx0(k)=Hatx1(k)-Hatx1(k-1);%累计还原得到历史数据的模拟值" x$ H- S+ `2 r% R" Y$ G0 p- J9 y4 z
end
q) \& v9 r7 q# k
for i=1:length(x0) %开始模型检验5 p2 {& b, u4 Q5 r& o
epsilon(i)=x0(i)-Hatx0(i);9 ?1 Z4 _8 U; B, L0 a! W
omega(i)=(epsilon(i)/x0(i))*100;
t5 s5 k6 F: p: h+ I8 s I" n; m
end
3 k0 H) H& [( \- Z9 |- s
% x0;Hatx0;epsilon;omega; %必要时去掉％得到各种数据, T5 f3 e- S8 z& h, H6 `4 q1 a# H
c=std(epsilon)/std(x0);p=0;
4 l! l8 Y& V- b3 j t+ z' Y
for i=1:length(x0)# v9 F( k: x, I& @; e
if abs(epsilon(i)-mean(epsilon))<0.6745*std(x0)) V' S2 @& N! ]& R
p=p+1;
{+ Y5 w0 e2 N/ Z
end
" w6 \0 @9 v6 ~
end9 e- _* R3 ]9 E _3 \0 P5 M4 ?% @) i% Z
p=p/length(x0)
{6 |1 g. h, ~9 ]! {
if p>0.95 & c<0.35
, d+ l- i) Y, m8 D
disp('The model is good,and the forecast is:'), r$ p' W4 A8 b, w' A
disp(Hatx0(length(x0)+T))
. A q1 G) r R5 H& m/ e) v- y
elseif p>0.85 & c<0.5
* s. D! ^) e- u
disp('The model is eligibility,and the forecast is:'),# @, B+ s: z* _5 B
disp(Hatx0(length(x0)+T))# \9 L( |. R, s& ]& H2 \
elseif p>0.7 & c>0.65
- ^- m4 T) I! l4 f. d
disp('The model is not good,and the forecast is:'),8 B4 j7 R6 f7 O. m$ l
disp(Hatx0(length(x0)+T))# }8 x5 O. B7 B
else p<=0.7 & c>0.65$ t) n3 J! e2 |0 x' Q; D
disp('The model is bad and try again')
/ P5 u6 k: B% v
end0 G- _" D4 `8 G
for i=1:length(x0)* F4 g7 u" c5 G6 E J! q
Hatx00(i)=Hatx0(i);
" p, A: j) r* V) D" }2 h6 j7 T+ C
end, n+ E" W5 I! p3 s9 V7 U4 j# K
z=1:length(x0);
- C; x0 n6 F, w' r
plot(z,x0,'-',z,Hatx00,':') %将原始数据和模拟值画在一个图上帮助观察
; M+ U8 A6 ]8 E7 Z$ W* m- ]
text(2,x0(2),'History data: real line')* z" Q/ i2 q- f
text(length(x0)/2,Hatx00(length(x0))/2,'Simulation data:broken line')+ Y0 u v) C# G" Q- D
end

复制代码

T=[2 3 4 5 3 2]
2 g8 j- Q9 p* Q. s9 m E3 v
Warning: Input arguments must be scalar.) ^- Z' X) z1 B; R3 a
> In fungry1 at 4% m2 ]5 q" U2 {8 r) S4 E8 t
Warning: Input arguments must be scalar.4 Z3 I2 ^1 y5 o$ v) p1 K1 R4 u
> In fungry1 at 5
3 b. f+ ^) T+ t* R3 p& ~; }0 N
Warning: Matrix is singular to working precision.* `, r9 P3 t9 E; O- c/ C
> In fungry1 at 17
9 |$ o# {: z6 `& Q( N( ~
! p* A( p. D, i2 b
HatA =" F0 z4 k( K/ N! W
8 f4 C) @- n+ f8 u
0
0 e5 `% Y7 j: P( a, I6 R
0
x3 R3 N* Q" V( C. @
! K0 x x' Z* Z1 \
) q8 F5 a7 [( x" X$ i; y
p =
1 ?7 v/ S7 v5 t1 l
9 v0 d! J- a5 E+ V7 v
0: }* Q- s- U& n9 g6 ?+ r
( q& {& ]' \% M7 v; o+ \
0 ^7 P# f: o* N8 M
ans =- {# u+ s! P9 p- _# m
' m, k" H0 |- a! W
0, X; v8 \9 S, A# f
: u) ^9 @( v, N. ]: g3 y; v4 \6 P
The model is bad and try again0 }- m O8 [' h7 \) G5 P a
??? Index exceeds matrix dimensions.
! a4 r" }. F. W9 I
$ U) K. [5 `) }' V: R8 b
Error in ==> fungry1 at 543 O1 n4 r( L; T5 d1 w
text(2,x0(2),'History data: real line')/ t& }% a" K2 |( T; H" N
( K/ j D6 D; R" T& N( D
>>

复制代码