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标题: BP神经网络程序问题求助 [打印本页]
作者: T-Eric    时间: 2014-7-18 21:13
标题: BP神经网络程序问题求助
这是我从书上打下来的代码，因为书的运行软件版本比较低，我的是Malab2013a的版本，所以我修改了部分程序，但运行出来有问题。请哪位高手帮忙指教和修正一下。谢谢！！7 K5 K+ o1 P$ v( N7 q6 x, D/ e. u1 X

: T( l7 J6 a: v# r; N% r%原始数据输入5 f9 j( K* D+ P; A: ~1 n" _
clc  F/ k; J  s! E5 v, j! J
sqrs=[20.55,22.44,25.73,27.13,29.45,30.1,30.96,34.06,36.42,38.09,39.13,39.99,...% E1 w2 s1 z( g: F4 ]4 H. i! ]
    41.93,44.59,47.30,52.89,55.73,56.76,59.17,60.63];+ X  H. E! Y0 w( C5 h
sqjdcs=[0.6,0.75,0.85,0.90,1.05,1.35,1.45,1.60,1.70,1.85,2.15,2.20,2.25,2.35,...0 w. N/ [8 q& P; ~! l# h! X
    2.5,2.6,2.7,2.85,2.95,3.10];: o8 P+ e( |7 r9 R3 f; z
sqglmj=[0.09,0.11,0.11,0.14,0.20,0.23,0.23,0.32,0.32,0.34,0.36,0.36,0.38,0.49,...
, y2 ^" v. P- o8 D    0.56,0.59,0.59,0.67,0.69,0.79];) X! C& `! S. \/ G$ y
glkyl=[5126,6217,7730,9145,10460,11387,12353,15750,18304,19836,21024,19490,20433,.../ y4 b( u9 Y  \% i- W
    22598,25107,33442,36836,40548,42927,43462];! `, B( U2 q- g$ T' W
glhyl=[1237,1379,1385,1399,1663,1714,1834,4322,8132,8936,11099,11203,10524,11115,...
- d$ y9 [& l' L  s0 _  a2 Z    13320,16762,18673,20724,20803,21804];# M% x& N! E' o9 w% J
p=[sqrs;sqjdcs;sqglmj];- U6 R  z3 t8 J+ d) k, n* [
t=[glkyl;glhyl];
% J- w, Y0 [% [* ]$ R( |1 j, o/ h; r1 ?3 A0 i' X4 _4 K
%数据归一化$ t* D% N! C( N3 C0 m$ @6 b2 x
[pn,ps1]=mapminmax(p);
6 M% k- l: Z: c2 K. r[tn,ps2]=mapminmax(t);4 D/ w$ p% P. i* |* i- O5 u
dx=[-1,1;-1,1;-1,1];2 d+ M. j' p9 k9 [- _

2 D  H+ K" x: r2 {( b9 T%BP网络训练8 i+ b# M* P4 I. X8 s
net=newff(p,t,[3,7,2],{'tansig','tansig','purelin'},'traingdx');* T8 \6 u$ y( N  d; D  w- s
net.trainParam.show=1000;
& x3 H6 z5 w* y1 o9 ]0 ]net.trainParam.Lr=0.05;
* e: `8 j0 d- e8 t( ^net.trainParam.epochs=50000;0 S5 m, C1 Y( R* N
net.trainParam.goal=0.65*10^(-3);
) m* _+ b/ o6 f5 u( anet=train(net,pn,tn);
1 \# @. G1 ~1 [3 d# T; R7 @! C2 Q2 G/ r" a
%利用原数据对BP网络仿真
0 v+ T  I5 I8 L; O, ^- [% V' {an=sim(net,pn);
! v) F. v/ `1 [" M3 aa=mapminmax('reverse',an,ps2);
# _1 T% j) A2 A+ \; I6 N6 A" O- O8 Z. T/ q
%仿真结果与原数据对比测试! a9 f! q; N& s8 I
x=1990:2009;* V; h: V# L4 m1 i
newk=a(1,:);
- K2 J, S, s' D1 r9 l" U2 [newh=a(2,:);
& s) r) R+ ?( B+ Tfigure(2);
1 r% D& c/ J& A" J* {" hsubplot(2,1,1);plot(x,newk,'r-o',x,glkyl,'b--+');
6 k0 Y+ f$ s+ |legend('网络输出客运量','实际客运量');
: ]0 [0 }/ x' v; G8 sxlabel('年份');ylabel('货运量、万人');# B* J& |# ?& d8 L* p
title('运用工具箱客运量学习和测试对比图');
" x/ v9 O9 Y. {7 b$ j: T% A0 Q" Ksubplot(2,1,2);plot(x,newh,'r-o',x,glhyl,'b--+');
' P  i# v0 `9 y- Slegend('网络输出货运量','实际货运量');
5 C$ c! @2 Q& e$ j  I7 f9 Fxlabel('年份');ylabel('货运量、万吨');
# ~+ O; J1 u( H* H3 ttitle('运用工具箱货运量学习和测试对比图');8 }3 E/ Y. x5 r* U% T/ j
  p6 Q' H! z( J  ^) c8 w
%新数据仿真" Y0 x( R% A8 v) E* Q
pnew=[73.39,75.552 y! W0 j! p/ r, X, R5 U8 I! X
    3.9635,4.0975# x" P+ q; Y& Q$ h1 b( w/ x
    0.9880,1.0268];9 S3 v$ B$ S' X0 m  i
pnewn=mapminmax('apply',pnew,ps1);
) x+ \5 x; y+ r6 X; C- K# E' Xanewn=sim(net,pnewn);6 G& F. Q1 t) V; W
anew=mapminmax('reverse',anewn,ps2)
& E) M7 @% w- f+ j# O% E% s
4 H% A! C' Q, F5 O/ t8 c

`VCWMZD9E$D~NHRR~AT9B4D.jpg (120.2 KB, 下载次数: 570)

`VCWMZD9E$D~NHRR~AT9B4D.jpg

作者: gancm    时间: 2014-7-19 12:30
看了图我感觉是网络输出后面那几个值太大了，前面基本都是一条水平线了，具体哪里还看不出问题。你把修改的地方说一下看看
作者: 529084167    时间: 2014-7-21 09:35
作者: T-Eric    时间: 2014-7-21 11:58
gancm 发表于 2014-7-19 12:30 " `/ c+ I% l& f) {6 p
看了图我感觉是网络输出后面那几个值太大了，前面基本都是一条水平线了，具体哪里还看不出问题。你把修改的 ...

$ Y, u( o) G( y' B3 U因为版本更新，Matlab中的Newff命令用法有所改变，原命令为：8 T6 V2 s6 v7 }6 k1 v- `9 R
net=newff(dx,[3,7,2]{'tansig','tansig','purelin'},'traingdx');5 f  N" Z: U  D" F6 p- Y
我修改为：: R$ b2 K( r) B
net=newff(p,t,[3,7,2],{'tansig','tansig','purelin'},'traingdx');) ^# L3 A5 v, {" l, d
然后有些命令被其他命令替代了，其中有premnmx，postmnmx，tramnmx命令好像被替换了，使用了一个强大的命令mapminmax。原命令为：  [$ b' |: r* }4 F+ H
[pn,minp,maxp,tn,mint,maxt]=premnmx(p,t);
+ v3 z  K& j. }2 @! H7 Sa=postmnmx(an,mint,maxt);  |2 E/ J2 ]2 H& f& ]. ?
pnewn=tramnmx(pnew,minp,maxp);
3 _3 g) h) g2 t$ K# U# r$ vanew=postmnmx(anewn,mint,maxt)
' C$ q: q+ `& ?) s( e2 ]我修改为：8 g* \. m( f3 j# }$ T" z% e- t
[pn,ps1]=mapminmax(p);[tn,ps2]=mapminmax(t);+ m. E$ [2 i9 q7 t' I0 l, u9 s% v7 r
a=mapminmax('reverse',an,ps2);- [" E7 R7 |  Y3 ^/ f
pnewn=mapminmax('apply',pnew,ps1);
+ R$ h/ D: }. ]; _: ?anew=mapminmax('reverse',anewn,ps2)4 n1 E& C* F$ ?$ O  l

+ L% m& i) M1 L3 u0 X5 s$ e1 r& o7 Y- `原程序为：
, @3 @- E! ?9 g0 O%原始数据输入% C  B- [# r$ @
clc
& L8 X" o+ _1 t4 H& Jsqrs=[20.55,22.44,25.73,27.13,29.45,30.1,30.96,34.06,36.42,38.09,39.13,39.99,...
; O' p2 m" \1 H    41.93,44.59,47.30,52.89,55.73,56.76,59.17,60.63];5 C+ o/ p) [* [
sqjdcs=[0.6,0.75,0.85,0.90,1.05,1.35,1.45,1.60,1.70,1.85,2.15,2.20,2.25,2.35,...( R: g" q* O6 s4 @8 M; k
    2.5,2.6,2.7,2.85,2.95,3.10];# H$ L, g$ `8 E8 k( s( ]- n# h
sqglmj=[0.09,0.11,0.11,0.14,0.20,0.23,0.23,0.32,0.32,0.34,0.36,0.36,0.38,0.49,...
' U/ Z7 S" t$ P; H    0.56,0.59,0.59,0.67,0.69,0.79];3 H) a/ C9 c: L6 [; ~
glkyl=[5126,6217,7730,9145,10460,11387,12353,15750,18304,19836,21024,19490,20433,.... ?+ z3 z; P! H' `* g
    22598,25107,33442,36836,40548,42927,43462];1 |, [& Y4 F/ F, d+ ^( x% r
glhyl=[1237,1379,1385,1399,1663,1714,1834,4322,8132,8936,11099,11203,10524,11115,...
/ B7 t2 u, {4 n, B) c    13320,16762,18673,20724,20803,21804];2 o, j( \  |5 H2 {& p, Y
p=[sqrs;sqjdcs;sqglmj];
1 E1 l7 R3 A  u  it=[glkyl;glhyl];/ [) T$ T3 ?- x& e" Y$ X+ n

8 O% I9 i+ g, Y; Q: Z1 l1 n%数据归一化0 q) t0 i! {8 f: l3 @- r& m# {0 {
[pn,minp,maxp,tn,mint,maxt]=premnmx(p,t);- A  Y+ s1 L6 D, h9 `, W
dx=[-1,1;-1,1;-1,1];
5 _0 Z+ \  z3 K( g' }+ z
. R( K8 y  x6 f+ c" u+ H, h9 v%BP网络训练. b5 [2 Q0 k8 f1 O0 H5 `1 \9 I8 |
net=newff(dx,[3,7,2],{'tansig','tansig','purelin'},'traingdx');+ y4 x7 r6 {1 T- f* U
net.trainParam.show=1000;
* p" n6 }( k! Q8 u; H# ^5 Ynet.trainParam.Lr=0.05;4 K" y; m) i9 V! G  _! E
net.trainParam.epochs=50000;
# @- @& m' @6 `5 p$ L7 Gnet.trainParam.goal=0.65*10^(-3);
* z5 @& X5 O+ i7 z- Unet=train(net,pn,tn);0 D( w( P/ |9 c/ D! }; d/ C* K

& i* \8 x( m+ V' d2 x- f%利用原数据对BP网络仿真% Y" ^7 E, O6 q! @
an=sim(net,pn);, {( o! Q' C/ v6 E" o1 G" U
a=postmnmx(an,mint,maxt);
. W, v5 N: H- L0 [6 G* ~$ b
7 ?+ N  J: l! a9 k! ]) e%仿真结果与原数据对比测试
) r$ B. t# O! U, }x=1990:2009;3 y+ H$ q, r; L4 l1 [
newk=a(1,;
' u  D; R9 D& i# J  j1 C( w) [' ~2 |newh=a(2,;  |6 O. t' z; @
figure(2);+ K% f( ]' U& h9 G
subplot(2,1,1);plot(x,newk,'r-o',x,glkyl,'b--+');
9 [! w8 V  c2 h, C' U) U5 c) C) ^: Flegend('网络输出客运量','实际客运量');) Q, T3 r7 G: H* n9 r
xlabel('年份');ylabel('货运量、万人');
1 B( t7 @" I( Z! ~, n" H) d& P6 atitle('运用工具箱客运量学习和测试对比图');
: e# \% X- w- Ysubplot(2,1,2);plot(x,newh,'r-o',x,glhyl,'b--+');" Q+ {8 W/ t1 C% c
legend('网络输出货运量','实际货运量');
+ O  L& v' v9 txlabel('年份');ylabel('货运量、万吨');) t; f7 m/ M6 _% j
title('运用工具箱货运量学习和测试对比图');
  ^% b2 h6 E, Y' Q7 U- f' Y& O3 F) y9 @* R2 d5 I0 v1 Q
%新数据仿真
% O7 H  f& e/ j& n4 n* y! {pnew=[73.39,75.55
8 a# Y( v; ?& \3 ?. h( A, \4 i) Q    3.9635,4.0975: V9 ?+ n5 b* ~* z% }- @7 t
    0.9880,1.0268];! u' }" Z! Y. ]; F
pnewn=tramnmx(pnew,minp,maxp);
% C* R' c% _: G) d+ `+ janewn=sim(net,pnewn);6 z; x$ }" K3 t+ b3 M
anew=postmnmx(anewn,mint,maxt)
' ^  [. v* u( s9 t6 I4 Q$ I6 K$ F, _. t; N9 T9 _2 k
修改后程序为：& k, p6 V. G. q3 P1 \: H  z
%原始数据输入
' K$ P' Z, }# kclc0 U: \2 ]/ ~" X5 D" \
sqrs=[20.55,22.44,25.73,27.13,29.45,30.1,30.96,34.06,36.42,38.09,39.13,39.99,...2 o$ \* e/ |1 b. X
    41.93,44.59,47.30,52.89,55.73,56.76,59.17,60.63];' n) F) P; B! h% d; Y  X7 W
sqjdcs=[0.6,0.75,0.85,0.90,1.05,1.35,1.45,1.60,1.70,1.85,2.15,2.20,2.25,2.35,...
, E  {) B+ H2 ^6 A, z- S- f    2.5,2.6,2.7,2.85,2.95,3.10];+ }, G! h9 A6 M- d- H( V, w) q0 {1 ?! g; _
sqglmj=[0.09,0.11,0.11,0.14,0.20,0.23,0.23,0.32,0.32,0.34,0.36,0.36,0.38,0.49,...
, K4 G* ]- ]" o9 M; c    0.56,0.59,0.59,0.67,0.69,0.79];5 z* M8 ^3 L  r2 o9 A
glkyl=[5126,6217,7730,9145,10460,11387,12353,15750,18304,19836,21024,19490,20433,...
; |1 ]. Z/ A- O' B4 f4 t    22598,25107,33442,36836,40548,42927,43462];
, ?* j4 c0 L# lglhyl=[1237,1379,1385,1399,1663,1714,1834,4322,8132,8936,11099,11203,10524,11115,...; T" v; m( J* b* }9 y. _
    13320,16762,18673,20724,20803,21804];" D( Q, u- ]- ^
p=[sqrs;sqjdcs;sqglmj];. }2 P$ Z" [0 v9 i4 f: w& m+ [5 c
t=[glkyl;glhyl];
1 X" D, V# a; ^' g$ l) O6 m# \" W' ^% [  c' K) o
%数据归一化9 F9 v5 _- P) W$ {9 w6 W
[pn,ps1]=mapminmax(p);! r5 Q2 {) O5 L" {- Q  q2 e: k
[tn,ps2]=mapminmax(t);
4 g5 y+ ]1 O$ E" w. M5 K) w4 v( D( L& s7 A) G! O0 [
%BP网络训练3 C; p# k' [) S2 i5 U1 F/ q9 N
net=newff(p,t,[3,7,2],{'tansig','tansig','purelin'},'traingdx');! F0 P3 @4 u: d( P
net.trainParam.show=1000;) C; ]* k0 m% k
net.trainParam.Lr=0.05;, v, w* f- S' X
net.trainParam.epochs=50000;& ^; k' [7 X9 R- X" C( X
net.trainParam.goal=0.65*10^(-3);
5 h1 l  X, J( f! W6 v$ onet=train(net,pn,tn);: k+ G# p. D0 a
' t$ B/ K& v9 K! Q# \1 W+ l% e4 k
%利用原数据对BP网络仿真1 T- X: F& `- x  y. R/ _
an=sim(net,pn);( D* B  j. i% m; X% O7 q( K( l
a=mapminmax('reverse',an,ps2);
; V# B& n# b$ _- ?
. q6 k% b$ t/ \* a; Q%仿真结果与原数据对比测试& Q$ G  _0 J! `, w! c; o5 p+ j
x=1990:2009;9 l2 Z/ ]1 Y+ d! b7 e# C# d+ e0 L
newk=a(1,;# c( @% o# V1 I& |  s
newh=a(2,;; K# U( Q$ u% ^% @$ m7 P) N9 x9 d
figure(2);/ f% z+ P; G6 j/ B4 ^
subplot(2,1,1);plot(x,newk,'r-o',x,glkyl,'b--+');
1 D- }! v0 E5 i- S. \+ H, }legend('网络输出客运量','实际客运量');
' Z8 U$ {9 C) ~$ a9 c" @xlabel('年份');ylabel('货运量、万人');
5 Z/ {% t4 J) k- h3 K$ z" Stitle('运用工具箱客运量学习和测试对比图');
0 I/ ?  m8 }+ ?subplot(2,1,2);plot(x,newh,'r-o',x,glhyl,'b--+');4 @) {0 A$ ?- ]7 a) T9 Z7 a8 B
legend('网络输出货运量','实际货运量');
' B# Z3 G9 p' {xlabel('年份');ylabel('货运量、万吨');7 s- f+ _, o' N) a9 X
title('运用工具箱货运量学习和测试对比图');4 {. a1 |+ O: ~& `" `1 j+ u
  X: K. }2 h6 P4 a
%新数据仿真
9 p3 S- U$ t: {* h; z5 upnew=[73.39,75.554 h7 p/ T. Q4 N6 p8 `- H
    3.9635,4.09757 e: L3 Q) a1 u8 e
    0.9880,1.0268];0 B$ y% P$ V0 K5 B) G7 {
pnewn=mapminmax('apply',pnew,ps1);9 d  h0 c/ C. C+ x; s4 F1 f
anewn=sim(net,pnewn);; K& i3 D+ {, q  `/ c  g
anew=mapminmax('reverse',anewn,ps2)
2 s+ [& ?* t  {（修改的地方用颜色标记了）+ X4 y1 k7 o( I/ j0 H; y- {3 O) }
麻烦您帮忙指出其中的问题，万分感谢！
作者: 且生    时间: 2014-7-21 18:05
求书名及页码……
作者: 且生    时间: 2014-7-21 18:20
  1. clc
    4 o( b6 U! q% C8 z! f8 l
  2. sqrs=[20.55,22.44,25.73,27.13,29.45,30.1,30.96,34.06,36.42,38.09,39.13,39.99,...
    9 {: z; F- P& Z' p* i
  3.     41.93,44.59,47.30,52.89,55.73,56.76,59.17,60.63];$ l) ?* Z* f( Z3 E! Z8 T
  4. sqjdcs=[0.6,0.75,0.85,0.90,1.05,1.35,1.45,1.60,1.70,1.85,2.15,2.20,2.25,2.35,...
    : g' `- n/ P+ j: K, [
  5.     2.5,2.6,2.7,2.85,2.95,3.10];+ @% s' k* g# C( a* Y% c2 K% }
  6. sqglmj=[0.09,0.11,0.11,0.14,0.20,0.23,0.23,0.32,0.32,0.34,0.36,0.36,0.38,0.49,...
      `* V! I1 M" v, y, l, ^" d" R" C. ]
  7.     0.56,0.59,0.59,0.67,0.69,0.79];
    , \3 v5 D0 W( \; K% e; ^
  8. glkyl=[5126,6217,7730,9145,10460,11387,12353,15750,18304,19836,21024,19490,20433,...
    3 b8 r% {, M3 j4 U- s+ k# p  _
  9.      22598,25107,33442,36836,40548,42927,43462];; D! `  ?- {4 d& w" I( d
  10. glhyl=[1237,1379,1385,1399,1663,1714,1834,4322,8132,8936,11099,11203,10524,11115,...
    4 }/ u" u: W* O5 y8 s1 g
  11.      13320,16762,18673,20724,20803,21804];% Z( n% _# M6 J. q
  12. p=[sqrs;sqjdcs;sqglmj];6 j+ s0 t( E2 d# ?* D. }+ N5 x
  13. t=[glkyl;glhyl];. N. O+ O5 h( C0 \
  14. %数据归一化& w% f  R6 Y+ x5 Q# C& Z9 ?
  15. [pn,ps1]=mapminmax(p);
    " Z! d& M5 M( b
  16. [tn,ps2]=mapminmax(t);
    : }, J7 Z0 r" G$ O6 `; o
  17. %dx=[-1,1;-1,1;-1,1];; i0 a/ `+ ^4 Y
  18. [color=Red] p0=minmax(pn);t0=minmax(tn);[/color]
    3 p9 M/ L2 w4 w2 u! [0 s4 u
  19. 9 }+ w( z/ `5 |! R
  20. %BP网络训练" ~, y  R' x2 l  A
  21. [color=Red] net=newff(p0,t0,[3,7,2],{'tansig','tansig','purelin'},'traingdx'); [/color]) C" X9 v3 X6 O
  22. net.trainParam.show=1000;
    ) ~1 ^( G$ N1 Y# ?( x3 U
  23. net.trainParam.Lr=0.05;
    " j: o, e' n3 |8 g
  24. net.trainParam.epochs=50000;
    0 D! I$ p; ^4 J* Y! t
  25. [color=Red] net.trainParam.goal=0.65*10^(-5);[/color]
    " w- r4 U4 Q: x3 S. ^
  26. net=train(net,pn,tn);1 H$ A( c8 f- Z/ G# }( h

  27. : F- c  c+ }. Y) J/ S' {# \
  28. %利用原数据对BP网络仿真# u4 R" X  u% _
  29. an=sim(net,pn);3 |* \4 L+ M% ~4 B# i4 Y
  30. a=mapminmax('reverse',an,ps2);5 R3 \8 n3 c+ l* Z

  31. . ^: v8 c0 `/ @5 h
  32. %仿真结果与原数据对比测试
    - \: _& J: P9 O3 H1 m2 ?1 `
  33. x=1990:2009;& E) f5 k6 D/ ^( n3 C  e
  34. newk=a(1,:);" B- L8 M+ V0 V
  35. newh=a(2,:);& ^. H7 [3 S" n1 X: g+ n
  36. figure(2);: ?( ?- a6 g* G( z
  37. subplot(2,1,1);plot(x,newk,'r-o',x,glkyl,'b--+');
    ! b1 w- y. b- G& o; M
  38. legend('网络输出客运量','实际客运量');
    5 C1 ?! g' T3 `4 @) x
  39. xlabel('年份');ylabel('货运量、万人');9 @# M1 |6 c6 J8 a! [& z
  40. title('运用工具箱客运量学习和测试对比图');
    3 }) h& H! f- I4 ~& i+ b
  41. subplot(2,1,2);plot(x,newh,'r-o',x,glhyl,'b--+');# }% v4 l$ B+ N- p; ^5 L( u1 ^
  42. legend('网络输出货运量','实际货运量');) ?5 a6 M8 v8 H4 ?  C9 \: E& T- p7 s
  43. xlabel('年份');ylabel('货运量、万吨');
    % b! l  v4 V/ q. c' x# D9 n& [; d
  44. title('运用工具箱货运量学习和测试对比图');8 I  t! J& `; s9 N2 k

  45. + k& F7 N3 K8 l1 U2 \8 s2 o: X$ p
  46. %新数据仿真9 S% p2 L+ ]( u' \7 }4 l+ l
  47. pnew=[73.39,75.55% \$ K* T/ v4 j: ]) m
  48.      3.9635,4.0975
    * n) l  K+ v+ ]5 M: [
  49.      0.9880,1.0268];7 u+ F2 W4 V; P4 i/ O
  50. pnewn=mapminmax('apply',pnew,ps1);
    6 M  L' e$ }2 X+ n# B3 C, ~
  51. anewn=sim(net,pnewn);, H+ |- f* v/ P
  52. anew=mapminmax('reverse',anewn,ps2)
复制代码
作者: 且生    时间: 2014-7-21 18:22
忽略我上面那个，改动的地方在18，21，25行……求批
  1. clc) k% T6 R* h, z* Q+ ~: M! i4 Q- s
  2. sqrs=[20.55,22.44,25.73,27.13,29.45,30.1,30.96,34.06,36.42,38.09,39.13,39.99,...
    7 R' P5 Z1 H, n5 O9 S6 T, h
  3.     41.93,44.59,47.30,52.89,55.73,56.76,59.17,60.63];
    - Q! J" e6 w" V+ s) K% {2 P
  4. sqjdcs=[0.6,0.75,0.85,0.90,1.05,1.35,1.45,1.60,1.70,1.85,2.15,2.20,2.25,2.35,...$ Q( `" p# e1 l6 o  W
  5.     2.5,2.6,2.7,2.85,2.95,3.10];5 t$ t  Z: I  I6 }/ Z
  6. sqglmj=[0.09,0.11,0.11,0.14,0.20,0.23,0.23,0.32,0.32,0.34,0.36,0.36,0.38,0.49,...
    3 }  i( d! i; \' P' o
  7.     0.56,0.59,0.59,0.67,0.69,0.79];6 {( T' D# N% F' F* B- g5 R6 ?
  8. glkyl=[5126,6217,7730,9145,10460,11387,12353,15750,18304,19836,21024,19490,20433,...
    * W) x3 C$ g3 _* F5 L, q4 d
  9.      22598,25107,33442,36836,40548,42927,43462];2 g3 u! Q3 C) ^% C
  10. glhyl=[1237,1379,1385,1399,1663,1714,1834,4322,8132,8936,11099,11203,10524,11115,...
    / a% J+ s7 T# K6 m5 s5 U4 {" i* M
  11.      13320,16762,18673,20724,20803,21804];% Z9 z. Q# o  W2 f
  12. p=[sqrs;sqjdcs;sqglmj];
    ( K2 q/ Q$ @/ g' \$ d
  13. t=[glkyl;glhyl];
    + K! _0 Z% Q  W6 f! U. S
  14. %数据归一化
    ) `) T7 C5 R, {4 q/ A- }8 _
  15. [pn,ps1]=mapminmax(p);
    5 D; x# q2 b1 g& m
  16. [tn,ps2]=mapminmax(t);1 W0 X- d1 W% @* w) }2 `3 G
  17. %dx=[-1,1;-1,1;-1,1];
    * P+ M0 `( Y2 f
  18. p0=minmax(pn);t0=minmax(tn);
    ) {( {) M- ?0 V  A

  19. 4 S0 r. B2 J7 N4 Y3 z
  20. %BP网络训练7 x5 U* J3 G1 B/ b  {" u- t- p- ^
  21. net=newff(p0,t0,[3,7,2],{'tansig','tansig','purelin'},'traingdx'); # ]3 z: F  i1 B3 w: e
  22. net.trainParam.show=1000;
      y0 Q1 z. e3 ~4 F0 U# q
  23. net.trainParam.Lr=0.05;0 S* q( X5 I/ p1 d; e9 i8 k
  24. net.trainParam.epochs=50000;2 w& [. Q% c- Q* j' u. N" y
  25. net.trainParam.goal=0.65*10^(-5);
    ) s$ A# D2 w! ^$ K
  26. net=train(net,pn,tn);$ y" A& C0 Z4 \4 Y
  27. ! b0 c* k5 h4 ]9 f
  28. %利用原数据对BP网络仿真
    ( v6 T9 F& f! {7 U
  29. an=sim(net,pn);
    0 R" n; q( v) L( C
  30. a=mapminmax('reverse',an,ps2);
    0 b# i  ?- a( i/ J
  31. % c" P5 F( V6 e' N
  32. %仿真结果与原数据对比测试 / A- t8 X4 N" I3 g' n
  33. x=1990:2009;
    # B; I# L# k: c! q8 o( v
  34. newk=a(1,:);1 |% T1 b5 [' }9 f# i4 [% Z
  35. newh=a(2,:);& v" Q4 b1 O% K+ \2 b
  36. figure(2);
    3 `$ I' f% S' H% P% E
  37. subplot(2,1,1);plot(x,newk,'r-o',x,glkyl,'b--+');  i- u+ W. y8 C% z
  38. legend('网络输出客运量','实际客运量');
    ' J) G7 F6 B5 h
  39. xlabel('年份');ylabel('货运量、万人');
    2 d6 K2 b8 o; }+ v0 n
  40. title('运用工具箱客运量学习和测试对比图');
    8 @# h) H! _% ?+ D+ J5 {
  41. subplot(2,1,2);plot(x,newh,'r-o',x,glhyl,'b--+');
    8 S! h% h, I2 Y. i# }. J) {
  42. legend('网络输出货运量','实际货运量');
    - T& Z( |2 T6 F% Y9 `$ y: T
  43. xlabel('年份');ylabel('货运量、万吨');
    ' w  g( w* }7 _) n3 U0 ]
  44. title('运用工具箱货运量学习和测试对比图');. B7 p! }8 w) X/ F" @
  45. - N" J" j2 d; a0 {  Z
  46. %新数据仿真) V! {' `8 ?& T* H% V
  47. pnew=[73.39,75.55
    % N- ?  k' o. m* d* X7 i' T
  48.      3.9635,4.0975, y  }" w* p2 Y! W7 O2 P0 u
  49.      0.9880,1.0268];( w7 s- G- u. D+ F. y
  50. pnewn=mapminmax('apply',pnew,ps1);3 b* `9 i) Q* A% H
  51. anewn=sim(net,pnewn);* o. X5 y& W* V3 M
  52. anew=mapminmax('reverse',anewn,ps2)
复制代码
作者: T-Eric    时间: 2014-7-22 21:14
且生 发表于 2014-7-21 18:22
( A) X" l4 D; z# Y4 F忽略我上面那个，改动的地方在18，21，25行……求批
$ F; J" t" Y) b+ x; a4 G) X$ L6 X
确实改善了很多，很是感谢。但效果还是不太理想，而且为何只学习了几十次就停了呢？即使我修改了目标精度。

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作者: 且生    时间: 2014-7-22 23:35
  1. %BP网络训练# X3 ^$ s2 G0 j# L8 X
  2. net=newff(p0,t0,6,{'tansig'},'traingd'); , H: F2 s/ A9 a2 X) n
  3. net.trainParam.show=1000;! K( n- L9 I1 O7 j9 b! `) s
  4. net.trainParam.Lr=0.05;
    & y" ~0 c+ u9 l
  5. net.trainParam.epochs=2000;
    3 X& M5 w" D3 B1 ?$ z- {/ D2 R
  6. net.trainParam.goal=0.65*10^(-4);7 s. w9 Z& U1 k- t
  7. net=train(net,pn,tn);
复制代码
我只改了这里面的，* s9 z5 B; b9 H. u8 p
一、改成单隐含层的，6个节点
  c4 n3 E# D  h- m% g. y; n二、训练函数改成梯度下降BP算法 traingd
; m( O) Q# _3 ^0 x% V  f三、迭代次数改成2000
" W, `) }9 F" a2 \! Y& t% R上面的参数是自己试的，我也不知道为什么。
4 h2 W: [: F/ i- I5 ?由于这玩意儿比较不靠谱，楼主多运行几次就能找到拟合的比较好的网络。
" l- M5 Y8 C# B/ Z关键问题是有没有过拟合我也不知道，等大神来解答吧
作者: 且生    时间: 2014-7-22 23:36
因为样本比较少，所以训练函数没有选会调节学习率的
作者: 狼之魂汪洋    时间: 2014-8-6 14:00
你这例题是在什么书上找的？
作者: T-Eric    时间: 2014-8-7 20:55
狼之魂汪洋 发表于 2014-8-6 14:00
9 T6 [. Z6 m4 I2 o; ~' o# K你这例题是在什么书上找的？
# _( H' E1 l. i/ s" r# u( o5 X; Y
就是那本《matalb在数学建模中的应用》



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