fix interger to a power bug

Uncertainty was incorrectly calculated when an integer was raised to a power where the power had some uncertainty.

metrolopy/ummy.py

@@ -958,10 +958,14 @@ def _pow(self,b):
  x = self._x**b._x
  dua = b._x*self._x**(b._x-1)*self._u
  lgx = log(self._x)
- try:
- lgx = type(self._x)(lgx)
- except:
- pass
+
+ # don't exactly remember why I did this,
+ # but it causes problems if x is int.
+ #try:
+ #lgx = type(self._x)(lgx)
+ #except:
+ #pass
+
  dub = lgx*self._x**b._x*b._u
  u = _combu(dua,dub,c)
 
@@ -1002,10 +1006,14 @@ def _rpow(self,b):
  raise ValueError('a negative number cannot raised to a power which has an uncertainty')
 
  lgb = log(b)
- try:
- lgb = type(b)(lgb)
- except:
- pass
+
+ # don't exactly remember why I did this,
+ # but it causes problems if x is int.
+ #try:
+ #lgb = type(b)(lgb)
+ #except:
+ #pass
+
  u = abs(b**self._x*lgb*self._u)
  refs = -self._refs if b < 0 else self._refs
  return type(self)(x,u,dof=self._ref,utype=refs)