作者joe7078 (Science & Truth)
看板MATLAB
標題[運算] 計算結果NaN (overflow?)
時間Tue Aug 21 15:08:49 2012
各位大大, 以下是我的原碼, eval算出來結果會是 NaN + NaN i
但是solve結果出來是有數值的, 請各位幫幫忙 ,謝謝 ^^
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% Initial parameters :
w1=2*pi*2971.1018e+6, w2=2*pi*2999.2858e+6, w3=2*pi*3108.1376e+6,
wa=2*pi*2990.8069e+6, wb=2*pi*3084.7899e+6, wc=2*pi*2999.0275e+6,
Ra=13.956e+6, Rb=8.975e+6, Rc=59.338e+6,
Qa=12344.4, Qb=7570.17, Qc=16415.8
L=Qa*Qb*Qc*Ra*Rb*Rc/(wa*wb*wc)
% Defien new parameters :
Ma1=w1^2-wa^2 , Mb1=w1^2-wb^2 , Mc1=w1^2-wc^2,
Ma2=w2^2-wa^2 , Mb2=w2^2-wb^2 , Mc2=w2^2-wc^2,
Ma3=w3^2-wa^2 , Mb3=w3^2-wb^2 , Mc3=w3^2-wc^2,
A1=Ma1 , B1=Mb1 , C1=Mc1,
A2=Ma2 , B2=Mb2 , C2=Mc2,
A3=Ma3 , B3=Mb3 , C3=Mc3,
D1= -2*(L^(-1/2))*w1^2,
D2= -2*(L^(-1/2))*w2^2,
D3= -2*(L^(-1/2))*w3^2,
E1=-Ma1*Mb1*Mc1*w1^(-4),
E2=-Ma2*Mb2*Mc2*w2^(-4),
E3=-Ma3*Mb3*Mc3*w3^(-4),
% Solved by MATLAB :
syms x y z
fun1=[A1*x^2 + B1*y^2 + C1*z^2 + D1*x*y*z + E1];
fun2=[A2*x^2 + B2*y^2 + C2*z^2 + D2*x*y*z + E2];
fun3=[A3*x^2 + B3*y^2 + C3*z^2 + D3*x*y*z + E3];
[x y z]=solve(fun1,fun2,fun3),
[eval(x) eval(y) eval(z)]
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