19 views (last 30 days)

Star Strider
on 18 Jan 2017

Your question seems to have changed. With respect to ‘wn(t)’ see my Comment in your original Question.

Try this:

syms wn t u_lim wn(t)

wn(t) = sym(1);

f = wn*exp(1i*2.*pi*t);

cplx_int = int(f, t, 0, 0.9)

cplx_int_n = vpa(cplx_int)

abs_cplx_int_n = abs(cplx_int_n)

cplx_int =

-(5^(1/2)*1i + (10 - 2*5^(1/2))^(1/2) - 3i)/(8*pi)

cplx_int_n =

- 0.093548928378863903321291906615298 + 0.03039588939177436951706748797891i

abs_cplx_int_n =

0.098363164308346596734748787414694

Star Strider
on 19 Jan 2017

My pleasure.

See if this does what you want:

syms wn t u_lim wn(t)

wn(t) = sym(1);

f = wn*exp(1i*2*pi*t);

upper_limit = vpasolve(abs(int(f, t, 0, u_lim)) == 0.9, u_lim)

abs_upper_limit = abs(upper_limit)

upper_limit =

61.226816497040968522581307264603 - 0.27736049247340612832400314608506i

abs_upper_limit =

61.227444722159630445299229455761

This is my previous code with 0.9 replacing 0.3.

Star Strider
on 23 Jan 2017

My pleasure.

If my Answer helped you solve your problem, please Accept it!

Sign in to comment.

Sign in to answer this question.

Opportunities for recent engineering grads.

Apply Today
## 1 Comment

## Direct link to this comment

https://www.mathworks.com/matlabcentral/answers/320999-definite-integral-with-an-exponential#comment_421394

⋮## Direct link to this comment

https://www.mathworks.com/matlabcentral/answers/320999-definite-integral-with-an-exponential#comment_421394

Sign in to comment.