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

8 O7 R- O/ z, J. m2 E7 R" _代码如下：
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clear all
9 U6 a" C$ F7 d6 |) l& g4 fclose all
clc
/ f! H* M1 k, b" E' L) K8 t' s5 H; c2 ksyms x y
& |/ y; S3 o1 s3 j% G7 Gomega=1;
mu=0.001;
) w  h) W% T* Y  `( ~alpha=0.13;
; `' f% x% m2 s5 V/ A5 l1 l2 Q' t/ ]beta=0.0031;
+ g, ]% l) o( m1 n2 eu=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;
omega2=1-u*cos(omega*tau)-v*omega*sin(omega*tau01);
# Z) s/ x) m# _eta=1+(1/mu)*(-(u/omega)*sin(omega*tau)+v*cos(omega*tau01));
K=D/(omega2.*(1+omega2.*(tau1.^2)));
! _. i1 f( _; I2 |+ J; d* ef1=(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)));
F1=int(int(f1,x,0,10),y,-10,10)
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0 i) X" _% P5 x+ c! O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

' S$ p# X5 `3 q4 V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
3 l/ |& y5 y, J/ d8 o- P$ Tdouble(F1)
3 M8 q3 g% l7 h& |' F% z, I1 B6 Y第一句加上这个

+ V6 \( L7 ^" k! E  v. N4 g可以了，谢谢哦

勇往直前11

来学习一下