No plot in double integral

조회 수: 3 (최근 30일)
Hexe
Hexe 2023년 1월 29일
댓글: Hexe 2023년 1월 30일
Hi! I try to solve the double integral, but there is an empty plot. Could you please tell me, what is wrong? In MathCad this integral is solved well.
n=1;
t=1;
r=1;
s=0:0.1:5;
fun = @(x,z,k) (x.*exp(2*n*t.*x.^2)./sqrt(1-x.^2)).*(exp(-2*t.*z.^2).*besselj(0,z.*k.*x).*(1+(sqrt(-pi)./(z*r)).*(1+((z*r).^2)/2).*(erfi(z*r/2)).*(exp(-((z*r).^2)/4))));
f3 = arrayfun(@(k)integral2(@(x,z)fun(x,z,k),0,Inf,0,1),s)
Warning: Inf or NaN value encountered.
Warning: The integration was unsuccessful.
Warning: Inf or NaN value encountered.
Warning: The integration was unsuccessful.
Warning: Inf or NaN value encountered.
Warning: The integration was unsuccessful.
Warning: Inf or NaN value encountered.
Warning: The integration was unsuccessful.
Warning: Inf or NaN value encountered.
Warning: The integration was unsuccessful.
Warning: Inf or NaN value encountered.
Warning: The integration was unsuccessful.
Warning: Inf or NaN value encountered.
Warning: The integration was unsuccessful.
Warning: Inf or NaN value encountered.
Warning: The integration was unsuccessful.
Warning: Inf or NaN value encountered.
Warning: The integration was unsuccessful.
Warning: Inf or NaN value encountered.
Warning: The integration was unsuccessful.
Warning: Inf or NaN value encountered.
Warning: The integration was unsuccessful.
Warning: Inf or NaN value encountered.
Warning: The integration was unsuccessful.
Warning: Inf or NaN value encountered.
Warning: The integration was unsuccessful.
Warning: Inf or NaN value encountered.
Warning: The integration was unsuccessful.
Warning: Inf or NaN value encountered.
Warning: The integration was unsuccessful.
Warning: Inf or NaN value encountered.
Warning: The integration was unsuccessful.
Warning: Inf or NaN value encountered.
Warning: The integration was unsuccessful.
Warning: Inf or NaN value encountered.
Warning: The integration was unsuccessful.
Warning: Inf or NaN value encountered.
Warning: The integration was unsuccessful.
Warning: Inf or NaN value encountered.
Warning: The integration was unsuccessful.
Warning: Inf or NaN value encountered.
Warning: The integration was unsuccessful.
Warning: Inf or NaN value encountered.
Warning: The integration was unsuccessful.
Warning: Inf or NaN value encountered.
Warning: The integration was unsuccessful.
Warning: Inf or NaN value encountered.
Warning: The integration was unsuccessful.
Warning: Inf or NaN value encountered.
Warning: The integration was unsuccessful.
Warning: Inf or NaN value encountered.
Warning: The integration was unsuccessful.
Warning: Inf or NaN value encountered.
Warning: The integration was unsuccessful.
Warning: Inf or NaN value encountered.
Warning: The integration was unsuccessful.
Warning: Inf or NaN value encountered.
Warning: The integration was unsuccessful.
Warning: Inf or NaN value encountered.
Warning: The integration was unsuccessful.
Warning: Inf or NaN value encountered.
Warning: The integration was unsuccessful.
Warning: Inf or NaN value encountered.
Warning: The integration was unsuccessful.
Warning: Inf or NaN value encountered.
Warning: The integration was unsuccessful.
Warning: Inf or NaN value encountered.
Warning: The integration was unsuccessful.
Warning: Inf or NaN value encountered.
Warning: The integration was unsuccessful.
Warning: Inf or NaN value encountered.
Warning: The integration was unsuccessful.
Warning: Inf or NaN value encountered.
Warning: The integration was unsuccessful.
Warning: Inf or NaN value encountered.
Warning: The integration was unsuccessful.
Warning: Inf or NaN value encountered.
Warning: The integration was unsuccessful.
Warning: Inf or NaN value encountered.
Warning: The integration was unsuccessful.
Warning: Inf or NaN value encountered.
Warning: The integration was unsuccessful.
Warning: Inf or NaN value encountered.
Warning: The integration was unsuccessful.
Warning: Inf or NaN value encountered.
Warning: The integration was unsuccessful.
Warning: Inf or NaN value encountered.
Warning: The integration was unsuccessful.
Warning: Inf or NaN value encountered.
Warning: The integration was unsuccessful.
Warning: Inf or NaN value encountered.
Warning: The integration was unsuccessful.
Warning: Inf or NaN value encountered.
Warning: The integration was unsuccessful.
Warning: Inf or NaN value encountered.
Warning: The integration was unsuccessful.
Warning: Inf or NaN value encountered.
Warning: The integration was unsuccessful.
Warning: Inf or NaN value encountered.
Warning: The integration was unsuccessful.
Warning: Inf or NaN value encountered.
Warning: The integration was unsuccessful.
f3 = 1×51
NaN NaN NaN NaN NaN NaN NaN NaN NaN NaN NaN NaN NaN NaN NaN NaN NaN NaN NaN NaN NaN NaN NaN NaN NaN NaN NaN NaN NaN NaN
Cor = ((-2*r*sqrt(2*n*t)*exp(-2*n*t))/(pi*erf(sqrt(2*n*t))*(atan(r/(2*sqrt(2*t)))-sqrt(2*t)/(2*r*(1/4+2*t/(r^2))))))*f3;
plot(s,Cor,'g-');
  댓글 수: 6
Walter Roberson
Walter Roberson 2023년 1월 29일
I did not notice that. I wonder what it would look like if you used sqrt(pi) instead?
n=1;
t=1;
r=1;
syms x z k s real
Pi = sym(pi);
fun = (x.*exp(2*n*t.*x.^2)./sqrt(1-x.^2)).*(exp(-2*t.*z.^2).*besselj(0,z.*k.*x).*(1+(sqrt(Pi)./(z*r)).*(1+((z*r).^2)/2).*(erfi(z*r/2)).*(exp(-((z*r).^2)/4))));
f3 = subs(int(int(fun,x,0,inf), z, 0, 1), k, s)
f3 = 
fun_zhalf = limit(subs(fun, k, 1), z, 1/2)
fun_zhalf = 
xlimited = limit(fun_zhalf, x, 1)
xlimited = 
case_to_plot = children(children(xlimited, 3),1)
case_to_plot = 
fplot(case_to_plot, [0 2])
xlimited = limit(fun_zhalf, x, 2)
xlimited = 
vpa(xlimited)
ans = 
You get rid of the real-valued portion of the function (at least at some values), but the complex portion remains.
Hexe
Hexe 2023년 1월 30일
Dear all, thank you for your replies. Yes, there is an imaginary part where sqrt(pi). And you are right, the integration is from 0 to 1 for x and 0-Inf for z. The math form is attached.

댓글을 달려면 로그인하십시오.

답변 (0개)

카테고리

Help CenterFile Exchange에서 Calculus에 대해 자세히 알아보기

Community Treasure Hunt

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

Start Hunting!

Translated by