| 1 | #-----------------------------------------------------------------------------
|
| 2 | #
|
| 3 | # Author : philippe.billet@noos.fr
|
| 4 | #
|
| 5 | # sgn sign function
|
| 6 | #
|
| 7 | #
|
| 8 | #-----------------------------------------------------------------------------
|
| 9 |
|
| 10 |
|
| 11 |
|
| 12 | Eval_sgn = ->
|
| 13 | push(cadr(p1))
|
| 14 | Eval()
|
| 15 | sgn()
|
| 16 |
|
| 17 | sgn = ->
|
| 18 | save()
|
| 19 | yysgn()
|
| 20 | restore()
|
| 21 |
|
| 22 | #define X p1
|
| 23 |
|
| 24 | yysgn = ->
|
| 25 |
|
| 26 | p1 = pop()
|
| 27 |
|
| 28 |
|
| 29 | if (isdouble(p1))
|
| 30 | if (p1.d > 0)
|
| 31 | push_integer(1)
|
| 32 | return
|
| 33 | else
|
| 34 | if (p1.d == 0)
|
| 35 | push_integer(1)
|
| 36 | return
|
| 37 | else
|
| 38 | push_integer(-1)
|
| 39 | return
|
| 40 |
|
| 41 | if (isrational(p1))
|
| 42 | if (MSIGN(mmul(p1.q.a,p1.q.b)) == -1)
|
| 43 | push_integer(-1)
|
| 44 | return
|
| 45 | else
|
| 46 | if (MZERO(mmul(p1.q.a,p1.q.b)))
|
| 47 | push_integer(0)
|
| 48 | return
|
| 49 | else
|
| 50 | push_integer(1)
|
| 51 | return
|
| 52 |
|
| 53 | if (iscomplexnumber(p1))
|
| 54 | push_integer(-1)
|
| 55 | push(p1)
|
| 56 | absval()
|
| 57 | power()
|
| 58 | push(p1)
|
| 59 | multiply()
|
| 60 | return
|
| 61 |
|
| 62 |
|
| 63 | if (isnegativeterm(p1))
|
| 64 | push_symbol(SGN)
|
| 65 | push(p1)
|
| 66 | negate()
|
| 67 | list(2)
|
| 68 | push_integer(-1)
|
| 69 | multiply()
|
| 70 | return
|
| 71 |
|
| 72 | ###
|
| 73 | push_integer(2)
|
| 74 | push(p1)
|
| 75 | heaviside()
|
| 76 | multiply()
|
| 77 | push_integer(-1)
|
| 78 | add()
|
| 79 | ###
|
| 80 |
|
| 81 | push_symbol(SGN)
|
| 82 | push(p1)
|
| 83 | list(2)
|
| 84 |
|
| 85 |
|