def oneEpsAsDeltas(eps, **tempOverride):
'''Takes an instance of Eps and rewrites it as Deltas'''
dim, indexRange = delta.getTempDimAndIndexRange(**tempOverride)
if not isinstance(eps,Eps):
raise TypeError('Error: input must be an Eps(*indecis)')
if not len(eps.index)==dim:
raise TypeError('Error: Eps must have dim number of indices')
termList=[]
for perm in permute_all(eps.index):
factorList=[ perm['parity'] ]
for (pos,index) in enumerate(perm['perm']):
factorList.append( delta.Delta(pos+1,index) )
termList.append(sympy.Mul(*factorList))
return sympy.Add(*termList)
def simplify_OneEps(eps, evalLevel=2, **tempOverride):
'''Takes an instance of Eps and tries to simplify. Returns 0 if any two indecis are equal. Rewrite eps as Deltas if the number of loose idecis (not in indexRange) of eps is equal to or less than evalLevel.'''
indexRange = delta.getTempDimAndIndexRange(**tempOverride)[1]
if not isinstance(eps,Eps):
raise TypeError('Error: input must be an Eps(*indecis)')
ints = 0
for (pos,ind) in enumerate(eps.index):
if ind in eps.index[ind+1:]:
return 0
if ind in indexRange:
if ind>len(eps.index) or ind<1:
ints += 1
if len(eps.index) - ints > evalLevel:
return eps
return delta.contractDeltas(epsAsDeltas(eps, **tempOverride),
**tempOverride)
