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POcreate new ctype python
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copied!<p>below classes are in pure python, but the are a little slow on heavily dense calculation and lead to about 1 minute to do about 5 million action.</p> <p><strong>the question</strong>:</p> <ol> <li>Is there any way to write them in C and import them to python for more speed?</li> <li>how?</li> </ol> <p>the usage is something like this:</p> <pre class="lang-py prettyprint-override"><code>_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... </code></pre> <p><strong>NOTE:</strong> the classes are bigger that what included here...</p> <pre class="lang-py prettyprint-override"><code>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 </code></pre> <p>and the other Class:</p> <pre class="lang-py prettyprint-override"><code>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 </code></pre>

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