# Revision history [back]

One way to get around this is to define the real and imaginary parts of the function and find roots of the sum of their squares:

sage: x = var('x')
sage: f = 1 - exp(I*x)
sage: fr = real_part(f)
sage: fi = imag_part(f)
sage: find_root(fr^2 + fi^2, -1, 1)
0.0


Calling full_simplify() on f = abs(1- exp(I*x)) returns a multiply of I which is clearly a real number (if x is a real number), but I don't know how to coax maxima or Sage into converting f into a explicitly real function of a real variable.