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旧 2009-04-01, 13:40   #3
laosam280
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注册日期: 2008-11-07
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默认 回复: [求助]这个积分需要加点什么条件能够得到合理的结果

另外,我这里有个能求解简单奇异积分的Gauss-Lagarre公式:
function I = IntGaussLager(f,n,AK,XK)
if(n<6 && nargin == 2)
AK = 0;
XK = 0;
else
I=sum(AK.*subs(sym(f),findsym(sym(f)),XK));
end

switch n
case 2,
I=0.853553*subs(sym(f),findsym(sym(f)),-0.585786)+...
0.146447*subs(sym(f),findsym(sym(f)),3.414214);

case 3,
I=0.711093*subs(sym(f),findsym(sym(f)),0.415575)+...
0.278518*subs(sym(f),findsym(sym(f)),2.294280)+...
0.0103893*subs(sym(f),findsym(sym(f)),6.289945);

case 4,
I=0.603154*subs(sym(f),findsym(sym(f)),0.322548)+...
0.357419*subs(sym(f),findsym(sym(f)),1.745761)+...
0.0388879*subs(sym(f),findsym(sym(f)),4.536620)+...
0.000539295*subs(sym(f),findsym(sym(f)),9.395071);

case 5,
I=0.521756*subs(sym(f),findsym(sym(f)),0.263560)+...
0.398667*subs(sym(f),findsym(sym(f)),1.413403)+...
0.0759424*subs(sym(f),findsym(sym(f)),3.596426)+...
0.00361176*subs(sym(f),findsym(sym(f)),7.085810)+...
0.0000233700*subs(sym(f),findsym(sym(f)),12.640801);
end
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