How can I fix the code?

I'm trying to calculate the sum of f(z1^i,z2^j) for i,i=1:2m and x1,x2 are chosen before (are nodes). Here is my code in Matlab
% code
k=5;r0=0.5; M=1000; m=100; h=r0/m;
ui=@(x,y) exp(5i*y);
a=@(x,y)( 0.01*exp(1-(0.25/(0.25-x.^2-y.^2))).*(x.^2+y.^2 < 0.25)+0.*( x.^2+y.^2 >=0.25));
% a=0.01*exp(1-(0.25/(0.25-x^2-y^2) if x^2+y^2 < 0.25 and a=0 otherwise.
f=@(x1,x2,y1,y2) -1i.*k.^2./4.*besselh(0,sqrt((x1-y1).^2+(x2-y2).^2)).*a(y1,y2).*ui(y1,y2);
s=0;
for p=1:2*m
x1=-r0+p*h;
for q=1:2*m
x2=-r0+q*h;
for i=1:2*m
z1=-r0+(i/2)*h;
for j=1:2*m
z2=-r0+(j/2)*h;
s=s+f(x1,x2,z1,z2);
disp(s);
disp(f(x1,x2,z1,z2));
end
end
end
Matlab can't show the results of 's' but can show the results of 'f(x1,x2,z1,z2)'. How can I fix the code?

2 commentaires

Walter Roberson
Walter Roberson le 30 Juil 2018
What happens if you try to display s? Is there an error message?
Anh Thu
Anh Thu le 31 Juil 2018
it display "NaN+NaNi"

Réponses (1)

OCDER
OCDER le 30 Juil 2018

0 votes

For some reason, you're getting a NaN + NaNi, a complex imaginary NaN. Try to skip these, otherwise s will just become NaN + NaN*i.
% code
k=5;r0=0.5; M=1000; m=100; h=r0/m;
ui=@(x,y) exp(5i*y);
a=@(x,y)( 0.01*exp(1-(0.25/(0.25-x.^2-y.^2))).*(x.^2+y.^2 < 0.25)+0.*( x.^2+y.^2 >=0.25));
% a=0.01*exp(1-(0.25/(0.25-x^2-y^2) if x^2+y^2 < 0.25 and a=0 otherwise.
f=@(x1,x2,y1,y2) -1i.*k.^2./4.*besselh(0,sqrt((x1-y1).^2+(x2-y2).^2)).*a(y1,y2).*ui(y1,y2);
s=0;
for p=1:2*m
x1=-r0+p*h;
for q=1:2*m
x2=-r0+q*h;
for i=1:2*m
z1=-r0+(i/2)*h;
for j=1:2*m
z2=-r0+(j/2)*h;
Out = f(x1,x2,z1,z2);
if ~isreal(Out); continue; end
s=s+Out;
disp(s);
disp(Out);
end
end
end
end

Cette question est clôturée.

Produits

Tags

Question posée :

le 30 Juil 2018

Clôturé :

le 20 Août 2021

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by