NaN value and two similar code:one correct & one with error

Question

Moein 2015-10-8

0
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此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/247426-nan-value-and-two-similar-code-one-correct-one-with-error

关闭： MATLAB Answer Bot 2021-8-20

hi friends i have two similar codes:

1)

a=6.62*(10^(-8));
h=[5.9e-06,0.8e-06,1.7e-06,1.7e-06];
k=6.62*(10^(-8));
L=[0.08,0.02];
s(1,1)=-h(1,1)/k;
s(1,2)=h(1,2)/k;
s(2,1)=-h(1,3)/k;
s(2,2)=h(1,4)/k;
j=[22.65037995,54.73643261,89.96745110,126.6631845,164.2134375,202.2829328,240.6796079,279.2910447,318.0491506,356.9110558,395.8487379,434.8432425,473.8813525,512.9536011,552.0530460,591.1744890,630.3139660,669.4684039,708.6353855,747.8129847;48.60546148,171.9080619,322.1146808,476.6215653,632.3771305,788.6531669,945.1940049,1101.887531,1258.676997,1415.530639,1572.429308,1729.360778,1886.316878,2043.291942,2200.281917,2357.283826,2514.295437,2671.315041,2828.341307,2985.373186];
for m=1:2
for n=1:20
f(m,1,n)=(((j(m,n)^2)+(s(m,1)*s(m,2)))^2)+(j(m,n)^2)*((s(m,2)-s(m,1))^2);
f(m,2,n)=L(1,m)*((j(m,n)^2)+(s(m,1)^2))*f(m,1,n);
f(m,3,n)=(s(m,2)-s(m,1))*((j(m,n)^4)-((j(m,n)^2)*s(m,1)*(s(m,2)-s(m,1)))-((s(m,1)^3)*s(m,2)));
end
end
for m=1:2
for n=1:20
A(m,n)=(2*f(m,1,n))/(f(m,2,n)+f(m,3,n));
end
end
for m=1:2
for n=1:20
B(m,n)=sin(j(m,n)*L(1,m))+(s(m,1)/j(m,n))*(cos(j(m,n)*L(1,m))-1);
end
end
for m=1:2
for n=1:20
C(m,n)=A(m,n)*B(m,n);
end
end
syms x y t
X=0
Y=0
for n=1:20
X=C(1,n)*(exp((-a)*(j(1,n)^2)*4586.735162*t))*(j(1,n)*cos(j(1,n)*0.08*x)-s(1,1)*sin(j(1,n)*0.08*x))+X;
Y=C(2,n)*(exp((-a)*(j(2,n)^2)*4586.735162*t))*(j(2,n)*cos(j(2,n)*0.08*y)-s(2,1)*sin(j(2,n)*0.08*y))+Y;
end
teta=(X*Y);
T=((7)*teta)+0.196;
V=subs(teta,[x y],[0.5 0.125]);
ezplot(V)

2)

h=[0.643,0.32,0.6876];
L=5.027;
j=[0,0.9334540347,3.420676259,6.432521384,9.525757414,12.64249311,15.76900707,18.90049224,22.03484279,25.17099331,28.30834773,31.44654673,34.58536093,37.72463707,40.86426886,44.00418027,47.14431549,50.28463265,53.42509969,56.56569167;0.3546720053,0.8850081993,1.469325286,2.073398719,2.685562967,3.301684906,3.920036274,4.539789000,5.160504554,5.781933044,6.403924081,7.026383246,7.649249090,8.272480151,8.896047187,9.519928280,10.14410561,10.76856326,11.39328562,12.01825636];
for n=1:20
f(1,1,n)=(((j(1,n)^2)-(h(1)*h(2)))^2)+(j(1,n)^2)*((h(2)+h(1))^2);
f(1,2,n)=((j(1,n)^2)+(h(1)^2))*f(1,1,n);
f(1,3,n)=(h(2)+h(1))*((j(1,n)^4)+((j(1,n)^2)*h(1)*(h(2)+h(1)))+((h(1)^3)*h(2)));
A(1,n)=(2*f(1,1,n))/(f(1,2,n)+f(1,3,n));
B(1,n)=sin(j(1,n))-(h(1)/j(1,n))*(cos(j(1,n))-1);
C(1,n)=A(1,n)*B(1,n);
C(2,n)=(2/(5.027*j(2,n)))*((besselj(1,5.027*j(2,n)))/(((besselj(0,5.027*j(2,n)))^2)+((besselj(1,5.027*j(2,n)))^2)));
end
syms z r t
Z=0
R=0
for n=1:20
Z=C(1,n)*(exp(-(j(1,n)^2)*t))*(j(1,n)*cos(j(1,n)*z)+h(1)*sin(j(1,n)*z))+Z;
R=C(2,n)*(exp(-(j(2,n)^2)*t))*besselj(0,j(2,n)*r)+R;
end
teta=(Z*R);
T=((38)*teta)+295;
V=subs(teta,[z r],[0.5 0]);
ezplot(V)

the first code works correctly but the second one errors for ezplot! the most important problem that happens in second code that is different from 1st one, is that when the value of z substitutes, V become NaN! not a sym fun. but in first code it becomes to a sym fun.

help me if you know the answer. best regards