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chinhuku

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duandian12

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麻烦大神们帮帮忙,我有数据x=2.822E-4,0.00495,0.00995,0.0197,0.03985,0.06047,0.07989,0.10009,0.14979,0.20018,0.24984,0.29978,0.39984,0.5003,0.60034,0.70045,0.79981,0.89997,0.99995,1.09996,1.19987,1.29989,1.40027,1.50004,1.59983,1.69939,1.79978,1.89995

y=7.5E-6,6.71875E-4,0.00391,0.0106,0.023,0.0358,0.04649,0.05719,0.08382,0.10749,0.13196,0.15581,0.20194,0.24542,0.2914,0.33464,0.37335,0.42031,0.46305,0.50221,0.54497,0.58705,0.62944,0.66904,0.71459,0.75343,0.79638,0.83817

想用方程y=y0*x*((1-y/y0)^a)*b*exp(-c/2311.3)进行拟合,求出参数y0,a,b,c。跪求各位支下招,小弟不胜感激..........
17楼2014-05-07 14:05:40
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lds588

铁杆木虫 (著名写手)

愚钝

【答案】应助回帖

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臭水沟(金币+5): 给力!给5个金币!理由:我们就需要像你这样的热心的虫子! 2011-05-28 09:07:21
CODE:
clear,clc
p=[0  0.001  0.002  0.003  0.004  0.005  0.006  0.008  0.011  0.014  0.019  0.023  0.03  0.037  0.048  0.06  0.08  0.1  0.136  0.17  0.217  0.279  0.388  0.444];
c=[0  0.307598804  0.538975997  0.777628765  0.959350561  1.069744162  1.190592446  1.340828541  1.512368753  1.643259589  1.769609554  1.903576465  2.027165658  2.151392907  2.294367083  2.425558327 2.598588163  2.723808495  2.912380082  3.049909679  3.206076964 3.386393547  3.644346885  3.758352826];
cc=c';
pp=p';
F=@(q,x)(x(:,1)-x(:,2)/q(1)).*(10.^(q(2)*(x(:,1)-x(:,2)/q(1)))+q(3))-x(:,2);   
x=[cc pp];

q0=[1    1     1];
warning off
q=nlinfit(x,zeros(size(x,1),1),F,q0);
disp('H A B分别为')
disp(num2str(q));
plot(x(:,1),x(:,2),'r^');hold on;
ezplot(@(x,y)F(q,[x,y]),[0,3.8,-0.1,0.5]);

[url=http://weibo.com/u/2577306830?s=6uyXnP][img]http://service.t.sina.com.cn/widget/qmd/2577306830/fa2fdb00/1.png[/img][/url]
2楼2011-05-28 00:27:57
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lds588

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愚钝

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为拟合得到图形,三角为原图,感觉 你的数据 不太适合用这个公式拟合~~~~
[url=http://weibo.com/u/2577306830?s=6uyXnP][img]http://service.t.sina.com.cn/widget/qmd/2577306830/fa2fdb00/1.png[/img][/url]
3楼2011-05-28 00:30:37
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forcal

禁虫 (初入文坛)

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臭水沟(金币+5): 不错!给5个金币!希望您常来交流!支持我们!3Q! 2011-05-28 09:09:49
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4楼2011-05-28 09:07:45
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