Please find error in this 1-line code: I'm using the <int> function for integration.

Please find error in this code: I'm using the int function for integration.

>> syms k

>> int(exp(-k)*cos(k),0,1)

This works, but...

>> syms k

>> int(exp(-k^2)*cos(k),0,1)

this does not work... I don't know what is wrong with this... I'm so frustrated...

Please help me.

[Mischa Kim]

Do you need a symbolic solution or would numeric suffice?

Answer 1

[Star Strider]

The problem is that int(exp(-k^2)) is essentially the ‘error function’. To the best of my knowledge, it has no closed-form analytic solution. Taking the Taylor series of the integrand and then integrating it seems to work:

syms k

f = exp(-k^2)*cos(k);

ft = taylor(f, k, 'Order',11)

ift = int(ft, k, 0, 1)

produces:

ift =

26172299/39916800

Experiment with it until you get the result you want.