二重积分求值

uaidenp

计算二重积分的时候，结果就是一个式子，不是积分值，这是为什么呢？求教
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/ A. M4 X" U+ O+ F8 s0 ?代码如下：
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3 V) ]9 I7 |3 T* Z+ O; Uclear all
close all
clc
" j# K4 ~0 j) c: Z" k. Z4 _. Nsyms x y
7 ~" t+ M+ x2 ?) a+ ^omega=1;
% ~9 I& j4 S0 K" _7 l' s% {% Vmu=0.001;
alpha=0.13;
beta=0.0031;
u=0.001;v=-0.02;
tau=2.2;tau1=1.5;D=0.11;
tau01=1.42;tau02=1.5;tau03=1.56;tau04=1.9;
# i+ U5 W5 C# Z* Z# O+ G7 Homega2=1-u*cos(omega*tau)-v*omega*sin(omega*tau01);
eta=1+(1/mu)*(-(u/omega)*sin(omega*tau)+v*cos(omega*tau01));
K=D/(omega2.*(1+omega2.*(tau1.^2)));
f1=(1./(omega2.*K)).*exp(-(mu./(1536.*K)).*(15.*beta.*(x.^2+y.^2./omega2).^4-32.*alpha.*(x.^2+y.^2./omega2).^3+96.*(x.^2+y.^2./omega2).^2-768.*eta.*(x.^2+y.^2./omega2)));
1 y" |$ R/ Z2 A, RF1=int(int(f1,x,0,10),y,-10,10)

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结果：
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int(int((1029484437153*exp((76368780973521777*(x^2 + (2251799813685248*y^2)/2297649917499219)^3)/922337203685477580800 - (17623564840043487*(x^2 + (2251799813685248*y^2)/2297649917499219)^2)/9223372036854775808 - (546330510041348097*(x^2 + (2251799813685248*y^2)/2297649917499219)^4)/590295810358705651712000 - (3488543873076974433998624506509*x^2)/81129638414606681695789005144064 - (1162847957692324811332874835503*y^2)/27593854166072889506733609713664))/34359738368, x, 0, 10), y, -10, 10)
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llbnmo

积分结果是个关于y的函数，如何转化成具体数值呢

lupkpu9

double(F1)
第一句加上这个

uaidenp

lupkpu9 发表于 2020-7-2 10:16
double(F1)
7 ?: o: v" e& T第一句加上这个

可以了，谢谢哦

勇往直前11

来学习一下