Equation is convergent but unable to extract the output

hello friends,

i run the below code and found that the equation is 'convergent', but i am unable to extract the output.

clc;close all;clear all;
syms m
k=360;      h=0.562;    theta=35;
alpha_m=((-1)*360*sqrt(1-((m^2)*(sind(theta)^2))));
term=(k*(1-(exp(-2*alpha_m*h)))/alpha_m);
y = vpa(symsum(term, m, 2, Inf));
if isinf(y)
    fprintf('divergent\n');
else
    fprintf('convergent\n');
end

I used

syms m
k=360;      h=0.562;    theta=35;
alpha_m=((-1)*360*sqrt(1-((m^2)*(sind(theta)^2))));
term=(k*(1-(exp(-2*alpha_m*h)))/alpha_m);
y = symsum(term, m, 2, Inf);
AA=double(y)       % but it didn't work

Please help me. Thanks in advance.

Answer 1

[Torsten]

The real part of y seems to converge, the imaginary part doesn't.

  k=360;      h=0.562;    theta=35;
  alpha_m = @(m)((-1)*360*sqrt(1-((m.^2)*(sind(theta)^2))));
  term = @(m)(k*(1-(exp(-2*alpha_m(m)*h)))./alpha_m(m));
  m = 2:10000;
  y = cumsum(term(m))
  plot(m,[real(y);imag(y)])