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标题: 求拟合代码 [打印本页]

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作者: woshiluyu666    时间: 2013-5-18 13:34
标题: 求拟合代码
t=[1,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,31,32,35,37,39,47];
x=[3,7,8,12,15,16,19,22,26,31,36,41,47,58,61,75,80,85,89,90,94,102,102,108,112,114,116,121,124,126,128,128,130,131];
plot(t,x,'*')
b0=[0.46,5.3,-0.45];
fun=inline('b(1)/(1+b(2)*exp(b(3)*t))','b','t');
[b,r,j]=nlinfit(t,x,fun,b0);
! Q7 ?" ]1 O# P6 Ab
; f* {4 Z' s  C+ e* i8 t6 `。。
0 f' M! q6 ]; o  i% j请问大神们，为什么老是出现错误呢，麻烦帮我检查fun=inline('b(1)/(1+b(2)*exp(b(3)*t))','b','t');
. l, A% e: X2 O+ F这句哪儿出错了，急求。。

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作者: madio    时间: 2013-8-20 17:49

1. t=[1,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,31,32,35,37,39,47];
   
2. x=[3,7,8,12,15,16,19,22,26,31,36,41,47,58,61,75,80,85,89,90,94,102,102,108,112,114,116,121,124,126,128,128,130,131];
   
3. plot(t,x,'*');
   ( a( M+ @6 \5 F, t0 z" {+ T3 Q
4. b0=[0.46,5.3,-0.45];
   
5. fun=inline('b(1)./(1+b(2)*exp(b(3)*t))','b','t');
   
6. [b,r,j]=nlinfit(t,x,fun,b0);
   ! m/ B5 ~0 y* f: m; G( r8 e
7. b

复制代码

改了一下，你试试看
( n+ s' ~4 E7 ~1 k, f

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作者: 净心、精心    时间: 2013-8-20 20:17
fun=inline('b(1)./(1+b(2)*exp(b(3)*t))','b','t');换成点除

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