Question: Another Dirac Plotting Query

I have been reaading previous posts on plotting Dirac functions; in particular: Plotting the Dirac Function and How do I plot Cos(w*t) in frequency domain?

Admittedly, I am still reading the help files with regard to understanding the use of the op() and map functions (I'm still in my first month of Maple); for example the difference in the second topic above:

F:=S->map(x->plottools[line]([-op([1,2],x),0],[-op([1,2],x),1]),[op(S)])

or

F:=S->map(x->plottools[line]([-op([2,1,2],x),0],[-op([2,1,2],x),op(1,x)]),[op(S)])

However, my main question relates to the use of complex functions. The examples seem to relate only to the fourier transform of cos functions. In my case I have sin and cos so the resulting fourier transform is complex. What I'd like to do however, is to plot the amplitude of this.

Not sure how to do this. I've started with a simple sin function and tried abs(); also tried to take the imaginary part . I keep getting "Error, (in unknown) improper op or subscript selector"

Is this simply due to my lack of understanding of the op function?

Best wishes

Karina