查看单个帖子
旧 2008-09-21, 17:20   #1
asus_tnt2
初级会员
 
注册日期: 2008-05-25
年龄: 42
帖子: 1
声望力: 0
asus_tnt2 正向着好的方向发展
问题 [求助]怎么对这个线性变化编程进行参数估计

两个方程:
X(c1x+c2y+c3)=a1x+a2y+a3
Y (c1x+c2y+c3)=b1x+b2y+b3
要估计a1~c3九个参数
现在已知 x,y 和 X,Y一共有34对数据点 我用nlinfit报错 说:

Warning: Divide by zero.
> In inlineeval at 13
In inline.subsref at 25
In nlinfit at 111
In asdf at 72
Warning: Divide by zero.
> In inlineeval at 13
In inline.subsref at 25
In nlinfit>LMfit at 271
In nlinfit at 168
In asdf at 72
Warning: Divide by zero.
> In inlineeval at 13
In inline.subsref at 25
In nlinfit>getjacobian at 474
In nlinfit>LMfit at 289
In nlinfit at 168
In asdf at 72
Warning: Divide by zero.
> In inlineeval at 13
In inline.subsref at 25
In nlinfit>getjacobian at 474
In nlinfit>LMfit at 289
In nlinfit at 168
In asdf at 72
Warning: Divide by zero.
> In inlineeval at 13
In inline.subsref at 25
In nlinfit>getjacobian at 474
In nlinfit>LMfit at 289
In nlinfit at 168
In asdf at 72
Warning: Divide by zero.
> In inlineeval at 13
In inline.subsref at 25
In nlinfit>getjacobian at 474
In nlinfit>LMfit at 289
In nlinfit at 168
In asdf at 72
Warning: Divide by zero.
> In inlineeval at 13
In inline.subsref at 25
In nlinfit>getjacobian at 474
In nlinfit>LMfit at 289
In nlinfit at 168
In asdf at 72
Warning: Divide by zero.
> In inlineeval at 13
In inline.subsref at 25
In nlinfit>getjacobian at 474
In nlinfit>LMfit at 289
In nlinfit at 168
In asdf at 72
Warning: Divide by zero.
> In inlineeval at 13
In inline.subsref at 25
In nlinfit>getjacobian at 474
In nlinfit>LMfit at 289
In nlinfit at 168
In asdf at 72
Warning: Divide by zero.
> In inlineeval at 13
In inline.subsref at 25
In nlinfit>getjacobian at 474
In nlinfit>LMfit at 289
In nlinfit at 168
In asdf at 72
Warning: Matrix is singular to working precision.
> In nlinfit>LMfit at 296
In nlinfit at 168
In asdf at 72
Warning: The model is overparameterized, and model parameters are not
identifiable. You will not be able to compute confidence or prediction
intervals, and you should use caution in making predictions.
> In nlinfit at 220
In asdf at 72

兄弟们帮帮我啊
asus_tnt2 当前离线   回复时引用此帖