def get_opC(i,spaceconfig,index,ordering,dag=False):
'''Get a C operator for site i and index index.'''
#ZL=[opunit_Z(spaceconfig,siteindex=j) for j in xrange(nsite)]
ci=opunit_C(spaceconfig,index=index,siteindex=i,dag=dag)
ci=prod([ci]+[opunit_Z(spaceconfig=spaceconfig,siteindex=j) for j in where(ordering<ordering[i])[0]])
if isinstance(ci,OpString):
ci.compactify()
return ci
def sweep_fidelity_f(kets,spaceconfig,maxN=None,usvmode=False):
'''
Sweep fidelity from center to edge, the version with fermionic sign.
Parameters:
:kets: len-2 list, the kets to sweep fidelity.
:maxN: int, the maximum retained singular value for usv mode, and the maximum retained states for direct mode.
:usvmode: bool, use usv mode if True.
'''
nsite=kets[0].nsite
bra=kets[0].tobra(labels=[kets[0].labels[0],kets[0].labels[1]+'\''])
ket=kets[1]
ordering=kets[0].forder
assert(allclose(ordering,arange(nsite)[::-1]))
if not usvmode and maxN is not None:
#compress datas
ket.compress(maxN=maxN)
bra.compress(maxN=maxN)
ket>>(nsite/2-ket.l,1e-8,Inf)
bra>>(nsite/2-bra.l,1e-8,Inf)
ket_bra=bra.toket()
bra_ket=ket.tobra()
#get SRLS(sign for right part) from right to left
site_axis=ket.site_axis
rlink_axis=ket.rlink_axis
llink_axis=ket.llink_axis
op=prod([opunit_Z(spaceconfig,siteindex=j) for j in xrange(nsite/2,nsite)])
#op=prod([OpUnitI(hndim=spaceconfig.hndim,siteindex=j) for j in xrange(nsite/2,nsite)])
SRLS=[]
for kt,br in [(ket,bra_ket),(ket_bra,bra)]:
if br is bra:
kt.chlabel('site',br.labels[0]+'2')
kt.chlabel('link',br.labels[1]+'2')
else:
br.chlabel('site',kt.labels[0]+'2')
br.chlabel('link',kt.labels[1]+'2')
SRL=[]
res=None
for i in xrange(nsite/2):
sitei=nsite-i-1
M=kt.get(sitei,attach_S='A')
MH=br.get(sitei,attach_S='A')
if i==0:
MH.labels[rlink_axis]=M.labels[rlink_axis]
opunit=op if isinstance(op,OpUnit) else op.query(sitei)[0]
MH.labels[site_axis]=M.labels[site_axis]+'\''
O=tensor.Tensor(opunit.get_data(),labels=[MH.labels[site_axis],M.labels[site_axis]])
items=[MH,O,M]
for item in items:
res=tensor.contract(res,item) if res is not None else item
SRL.append(res.diagonal())
assert(sum(abs(res))-sum(abs(res.diagonal()))<1e-5)
SRLS.append(SRL)
SRLS=zip(SRLS)
#calculation
edge_labels_l=[bra.AL[-1].labels[rlink_axis],ket.AL[-1].labels[rlink_axis]]
bra.BL[0].labels[llink_axis]+='@'
ket.BL[0].labels[llink_axis]+='@'
edge_labels_r=[bra.BL[0].labels[llink_axis],ket.BL[0].labels[llink_axis]]
if usvmode:
Ci=USVobj(U=tensor.Tensor(diag(bra.S)[:,newaxis,:],labels=[edge_labels_l[0],'null',edge_labels_r[0]]),S=None,\
V=tensor.Tensor(diag(ket.S)[:,newaxis,:],labels=[edge_labels_l[1],'null',edge_labels_r[1]]))
else:
Ci=tensor.Tensor(diag(bra.S),labels=[edge_labels_l[0],edge_labels_r[0]])*tensor.Tensor(diag(ket.S),labels=[edge_labels_l[1],edge_labels_r[1]])
fs=[1]
SL=[]
for i in xrange(ket.nsite/2):
t0=time.time()
site_l=nsite/2-i-1
site_r=nsite/2+i
if usvmode:
t0=time.time()
Li=USVobj(U=bra.get(site_l,attach_S='B'),S=None,V=ket.get(site_l,attach_S='B'))
Ci=Li.join(Ci)
print Ci
Ci=Ci.compress(min(maxN,min(Ci.shape)))
Ri=USVobj(U=bra.get(site_r,attach_S='A'),S=None,V=ket.get(site_r,attach_S='A'))
Ci=Ci.join(Ri)
print Ci
t1=time.time()
Ci=Ci.compress(min(maxN,min(Ci.shape)))
t2=time.time()
print 'Elapse -> %s, %s'%(t1-t0,t2-t1)
fi=sum(Ci.S)
print Ci,Ci.S.min()
SL.append(Ci.S)
else:
#get the sign
SK,SB=SRLS[nsite/2-i-1]
pdb.set_trace()
Ci=bra.get(site_l,attach_S='B')*(ket.get(site_l,attach_S='B')*Ci)*bra.get(site_r,attach_S='A')*ket.get(site_r,attach_S='A')
pdb.set_trace()
#Ci=tensor.contract(mpses)
Ci=Ci.chorder(array([0,2,1,3]))
S=svdvals(Ci.reshape([Ci.shape[0]*Ci.shape[1],-1]))
fi=sum(S)
SL.append(S)
fs.append(fi)
t1=time.time()
print '%s F->%s, Elapse->%s'%(i,fi,t1-t0)
save('data/SL.npy',SL)
return fs