2

下面的类是纯python，但是在密集计算上有点慢，导致大约1分钟完成大约500万个动作。

问题：

  1. 有没有办法用 C 语言编写它们并将它们导入 python 以提高速度？
  2. 如何？

用法是这样的：

_cm=Unit(...)  # Unit
_m =Unit(...)  # Unit
a= 1*_cm  # UnitValue
b= 2*_m  # UnitValue
_m2 = _m**2  # Unit
b*a == 0.02 * _m2  # UnitValue
a*b == 200  * _cm2   # UnitValue # _cm2 is auto created unit based on Unit.__new__
b-a = 0.99*_m  # UnitValue
a-b = -99*_cm  # UnitValue
# and so on...

注意：课程比这里包含的要大...

class Unit(object):
    def __new__(self, *args, **kwargs):
        # check if this unit not created before and if ues return before created-one.
        # useful for cmp between units.
        return created_or_new_unit_instance

    def __div__(self, other):
        return self * (other ** -1)     # self / other

    def __rdiv__(self, other):
        return other * (self ** -1)     # other / self

    def __rmul__(self, other):
        return self * other             # other * self


    def __mul__(self, other):       # self * other
        if isinstance(other, SUPPORTED_NUMBERS):
            return UnitValue(other, self)

        elif isinstance(other, UnitValue):  # FIXME DOUBLICATED!
            return (other.value * (other.unit * self))

        elif isinstance(other, Unit):  # multipling two units self * other
            # calculate the other exchange factor againest self in `v`
            if v == 1.0:
                # the bases may differ from self.bases or other.bases
                # so just create a new Unit and let __new__ handle doublication.
                return Unit(bases)
            else:
                return v * Unit(bases)

        return NotImplemented

    def __pow__(self, other, modulo=None):  # @UnusedVariable
        # create new powered unit.
        return new Unit

和另一个类：

class UnitValue(object):
    def __init__(self, value, unit):
        self.value           = value
        self.unit            = unit


    def __add__(self, other):       # self + other
        if isinstance(other, UnitValue):
            o    = self.unit.get_unitvalue_in_this_unit(other)  # other is UnitValue
            v    = self.value + o.value
            return UnitValue(v, self.unit)

        if other == 0:
            return UnitValue(self.value, self.unit)

        return NotImplemented


    def __mul__(self, other):    # self * other
        if isinstance(other, SUPPORTED_NUMBERS):
            return UnitValue(other * self.value, self.unit)

        elif isinstance(other, UnitValue):
            return (self.value * other.value) * (self.unit * other.unit)

        return NotImplemented


    def __pow__(self, other, modulo=None):
        v    = self.value ** other
        u    = self.unit ** other
        if modulo:
            v    = v % modulo

        return UnitValue(v, u)


    def __cmp__(self, other):
        if isinstance(other, UnitValue):
            vo   = self.unit.get_unitvalue_in_this_unit(other).value
        else:
            vo   = other
        if vo is None:
            vo = 0

        diff     = self.value - vo
        epsi     = 1e-10
        if abs(diff) < epsi: return  0
        elif    diff > 0:    return  1
        elif    diff < 0:    return -1
4

0 回答 0