# Do the exponential cosine function.



Eval_expcos = ->
  push(cadr(p1))
  Eval()
  expcos()

expcos = ->
  save()

  p1 = pop()

  push(imaginaryunit)
  push(p1)
  multiply()
  exponential()
  push_rational(1, 2)
  multiply()

  push(imaginaryunit)
  negate()
  push(p1)
  multiply()
  exponential()
  push_rational(1, 2)
  multiply()

  add()

  restore()