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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6 C; k! T. i6 Z! }代码如下：
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/ Z5 j) U1 Z% aclear all
close all
clc
, `" d' d& l7 m' usyms x y
  F5 i4 N" N5 F9 `- nomega=1;
$ l+ i0 S% D) _1 N) t" l; nmu=0.001;
1 X, J/ i1 r2 Ialpha=0.13;
! x7 X/ S$ M( P- Tbeta=0.0031;
u=0.001;v=-0.02;
tau=2.2;tau1=1.5;D=0.11;
5 e' X3 I: M# Q$ ^8 X' G2 o' }tau01=1.42;tau02=1.5;tau03=1.56;tau04=1.9;
omega2=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)));
5 d+ W* r. y( af1=(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)));
# n: @3 ]6 B: N) c# A) W3 `. SF1=int(int(f1,x,0,10),y,-10,10)

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! V, F3 S, f; P3 z& a6 R结果：
F1=
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)
6 r! U1 W  J3 ]第一句加上这个

uaidenp

lupkpu9 发表于 2020-7-2 10:16
& X2 a. h- ~" k% jdouble(F1)
第一句加上这个

9 }& P' ]* i! e可以了，谢谢哦
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勇往直前11

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