#-----------------------------------------------------------------------------
#
#  Author : philippe.billet@noos.fr
#
#  sgn sign function
#
#
#-----------------------------------------------------------------------------



Eval_sgn = ->
  push(cadr(p1))
  Eval()
  sgn()

sgn = ->
  save()
  yysgn()
  restore()

#define X p1

yysgn = ->
  
  p1 = pop()

  
  if (isdouble(p1))
    if (p1.d > 0) 
      push_integer(1)
      return
    else 
      if (p1.d == 0) 
        push_integer(1)
        return
      else
        push_integer(-1)
        return

  if (isrational(p1))
    if (MSIGN(mmul(p1.q.a,p1.q.b)) == -1) 
      push_integer(-1)
      return
    else 
      if (MZERO(mmul(p1.q.a,p1.q.b))) 
        push_integer(0)
        return
      else
        push_integer(1)
        return

  if (iscomplexnumber(p1))
    push_integer(-1)
    push(p1)
    absval()
    power()
    push(p1)
    multiply()
    return
  
  
  if (isnegativeterm(p1))
    push_symbol(SGN)
    push(p1)
    negate()
    list(2)
    push_integer(-1)
    multiply()
    return
  
  ###
  push_integer(2)
  push(p1)
  heaviside()
  multiply()
  push_integer(-1)
  add()
  ###
  
  push_symbol(SGN)
  push(p1)
  list(2)