Double integration problem (can not use symbolic math tool box)

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I have a function of two variable to double integrate but i can not use symbolic integration as i want to compile this to .exe file.
clc;
sig=0.5;
L=4;
k=1.0472;
k_sig=k*sig;
kls=k*ls;
er=3.5;
theta=(0:10:70)';
g=length(theta);
Q=zeros(g,1);
for i=1:g;
cs=cosd(theta(i)); s=sind(theta(i)); s2=s.*s; cs2=cs.*cs;
ks=k.*sig; kL=k.*L; ks2=ks.*ks; kL2=kL.*kL;
%(*Integration variables*)
r2=@(r)(r.*r); sf=@(phi)sin(phi); csf=@(phi)cos(phi);
rx=@(r,phi)(r.*csf(phi)); ry=@(r,phi)(r.*sf(phi));
Wmh=0; Wnh=0.0;
for n=1:4;
for m=1:4;
wn=@(r,phi)(n.*kL2./(n.*n + kL2.*((rx(r,phi) - s).^2...
+ ry(r,phi).^2))^1.5);
wm=@(r,phi)(m.*kL2./(m.*m + kL2.*((rx(r,phi) + s).^2...
+ ry(r,phi).^2))^1.5);
vhmn=((ks2.*cs2).^(n+m))./(factorial(m).*factorial(n));
Wm=@(r,phi)(vhmn.*wn(r,phi).*wm(r,phi));
Wmh=@(r,phi)(Wmh(r,phi)+Wm(r,phi));
end
end
Wnh=@(r,phi)(Wnh(r,phi)+Wmh(r,phi));
VH=@(r,phi)(Wnh(r,phi).*r);
%% Double Integration
Q(i)=quad2d(VH,0,1,0,pi/4);
end
HV=10*log10(Q);
table=[theta HV]
This is giving Error:
Error:
Subscript indices must either be real positive integers or logicals.
Error in @(r,phi)(Wnh(r,phi)+Wmh(r,phi))
Error in @(r,phi)(Wnh(r,phi).*r)
Error in quad2d/tensor (line 344)
Z = FUN(X,Y); NFE = NFE + 1;
Error in quad2d (line 168)
[Qsub,esub] = tensor(thetaL,thetaR,phiB,phiT);
Error in Untitled1 (line 32)
Q(i)=quad2d(VH,0,1,0,pi/4);
>>

Accepted Answer

Matt Fig
Matt Fig on 26 Sep 2012
You have a couple of errors. One is you didn't define the base recursion functions to be functions but doubles - this is where your error comes from. Second you didn't use .^ everywhere instead of ^.
clc;
sig=0.5;
L=4;
k=1.0472;
k_sig=k*sig;
kls=k*ls;
er=3.5;
theta=(0:10:70)';
g=length(theta);
Q=zeros(g,1);
for i=1:g;
cs=cosd(theta(i)); s=sind(theta(i)); s2=s.*s; cs2=cs.*cs;
ks=k.*sig; kL=k.*L; ks2=ks.*ks; kL2=kL.*kL;
%(*Integration variables*)
r2=@(r)(r.*r); sf=@(phi)sin(phi); csf=@(phi)cos(phi);
rx=@(r,phi)(r.*csf(phi)); ry=@(r,phi)(r.*sf(phi));
Wmh=@(x,y) 0; Wnh=@(x,y) 0*x;
for n=1:4;
for m=1:4;
wn=@(r,phi)(n.*kL2./(n.*n + kL2.*((rx(r,phi) - s).^2 ...
+ ry(r,phi).^2)).^1.5);
wm=@(r,phi)(m.*kL2./(m.*m + kL2.*((rx(r,phi) + s).^2 ...
+ ry(r,phi).^2)).^1.5);
vhmn=((ks2.*cs2).^(n+m))./(factorial(m).*factorial(n));
Wm=@(r,phi)(vhmn.*wn(r,phi).*wm(r,phi));
Wmh=@(r,phi)(Wmh(r,phi)+Wm(r,phi));
end
end
Wnh=@(r,phi)(Wnh(r,phi)+Wmh(r,phi));
VH=@(r,phi)(Wnh(r,phi).*r);
%%Double Integration
Q(i)=quad2d(VH,0,1,0,pi/4);
end

More Answers (1)

Jan
Jan on 26 Sep 2012
Edited: Jan on 26 Sep 2012
Initially you defined:
Wnh = 0.0;
Later you replace this by:
Wnh = @(r,phi)(Wnh(r,phi)+Wmh(r,phi));
Now in the first call of "Wnh(r,phi)" the term "Wnh" is a scalar array and "r,phi" is interpreted as index. And indices must be positive integers.
Are you sure you want to define the function handle Wnh recursively?!

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