eH = cytnx.UniTensor(eH,2) eH.print_diagram() print(eH) H = cytnx.UniTensor(H,2) H.print_diagram() ## Create MPS: # # | | # --A-la-B-lb-- # A = cytnx.UniTensor([cytnx.Bond(chi),cytnx.Bond(2),cytnx.Bond(chi)],rowrank=1,labels=[-1,0,-2]); B = cytnx.UniTensor(A.bonds(),rowrank=1,labels=[-3,1,-4]); cytnx.random.Make_normal(B.get_block_(),0,0.2); cytnx.random.Make_normal(A.get_block_(),0,0.2); A.print_diagram() B.print_diagram() #print(A) #print(B) la = cytnx.UniTensor([cytnx.Bond(chi),cytnx.Bond(chi)],rowrank=1,labels=[-2,-3],is_diag=True) lb = cytnx.UniTensor([cytnx.Bond(chi),cytnx.Bond(chi)],rowrank=1,labels=[-4,-5],is_diag=True) la.put_block(cytnx.ones(chi)); lb.put_block(cytnx.ones(chi)); la.print_diagram() lb.print_diagram() #print(la) #print(lb)
eH = cytnx.UniTensor(eH, 2)
eH.tag() # this will tag with in/out(ket/bra) on each bond.
eH.print_diagram()
H = cytnx.UniTensor(H, 2)
H.tag()
H.print_diagram()
## Create MPS, with bond tagged with direction in/out(ket/bra):
# ^ ^
# | |
# ->-A-> ->la-> ->B-> ->lb->
#
A = cytnx.UniTensor([
cytnx.Bond(chi, cytnx.BD_KET),
cytnx.Bond(2, cytnx.BD_BRA),
cytnx.Bond(chi, cytnx.BD_BRA)
],
rowrank=1,
labels=[-1, 0, -2])
B = cytnx.UniTensor(A.bonds(), rowrank=1, labels=[-3, 1, -4])
cytnx.random.Make_normal(B.get_block_(), 0, 0.2)
cytnx.random.Make_normal(A.get_block_(), 0, 0.2)
A.print_diagram()
B.print_diagram()
#print(A)
#print(B)
la = cytnx.UniTensor(
[cytnx.Bond(chi, cytnx.BD_KET),
cytnx.Bond(chi, cytnx.BD_BRA)],
H.reshape_(2, 2, 2, 2)
eH = cytnx.UniTensor(eH, 2)
eH.print_diagram()
print(eH)
H = cytnx.UniTensor(H, 2)
H.print_diagram()
## Create MPS:
#
# | |
# --A-la-B-lb--
#
A = cytnx.UniTensor(
[cytnx.Bond(chi), cytnx.Bond(2),
cytnx.Bond(chi)],
rowrank=1,
labels=[-1, 0, -2])
B = cytnx.UniTensor(A.bonds(), rowrank=1, labels=[-3, 1, -4])
cytnx.random.Make_normal(B.get_block_(), 0, 0.2)
cytnx.random.Make_normal(A.get_block_(), 0, 0.2)
A.print_diagram()
B.print_diagram()
#print(A)
#print(B)
la = cytnx.UniTensor([cytnx.Bond(chi), cytnx.Bond(chi)],
rowrank=1,
labels=[-2, -3],
is_diag=True)
lb = cytnx.UniTensor([cytnx.Bond(chi), cytnx.Bond(chi)],
# which is the same in this model, but in general they could be different
Hup = H
Hdown = Hup.clone()
## Hamiltonain
Hu = cy.UniTensor(Hup, 3)
Hd = cy.UniTensor(Hdown, 3)
## create 3PESS:
s1 = cy.UniTensor(cy.random.normal([D, D, D], 0, 0.5), 0)
s2 = s1.clone()
A = cy.UniTensor(cy.random.normal([D, 2, D], 0, 0.5), 2)
B = cy.UniTensor(cy.random.normal([D, 2, D], 0, 0.5), 2)
C = cy.UniTensor(cy.random.normal([D, 2, D], 0, 0.5), 2)
Ls1 = [
cy.UniTensor([cy.Bond(D), cy.Bond(D)], rowrank=1, is_diag=True)
for i in range(3)
]
for i in Ls1:
i.put_block(cy.ones(D))
Ls2 = [i.clone() for i in Ls1]
## gates:
eHu = cy.linalg.ExpH(Hu, -tau)
eHd = cy.linalg.ExpH(Hd, -tau)
## iterator:
Eup_old, Edown_old = 0, 0
cov = False
for i in range(maxit):
Tn3 = cytnx.zeros(10, device=cytnx.Device.cpu)
print(Tn)
print(Tn2)
print(Tn3)
Tna = cytnx.zeros((2, 3))
Tn2a = cytnx.zeros((2, 3), dtype=cytnx.Type.Float)
Tn3a = cytnx.zeros((2, 3), device=cytnx.Device.cpu)
print(Tna)
print(Tn2a)
print(Tn3a)
##=============================
## Bond
##=============================
bd_in = cytnx.Bond(10, cytnx.bondType.BD_BRA)
print(bd_in)
bd_sym = cytnx.Bond(3,cytnx.bondType.BD_KET,\
[[0,2],[1,2],[1,3]],\
[cytnx.Symmetry.Zn(2),\
cytnx.Symmetry.U1()])
print(bd_sym)
print(bd_sym == bd_sym)
bd_1 = cytnx.Bond(3)
bd_2 = cytnx.Bond(2)
bd_3 = cytnx.Bond(4)
U = cytnx.UniTensor([bd_1, bd_2, bd_3], Rowrank=2, dtype=cytnx.Type.Double)
U.print_diagram()
## # Author: Kai-Hsin Wu ## #Example of 1D Heisenberg model ## iTEBD ##------------------------------------- chi = 40 J = 1.0 CvgCrit = 1.0e-12 dt = 0.1 ## Create Si Sj local H with symmetry: ## SzSz + S+S- + h.c. bdi = cytnx.Bond(2, cytnx.BD_KET, [[1], [-1]]) bdo = bdi.clone().set_type(cytnx.BD_BRA) H = cytnx.UniTensor([bdi, bdi, bdo, bdo], labels=[2, 3, 0, 1], rowrank=2) ## assign: # Q = 2 # Q = 0: # Q = -2: # [1] [[ -1, 1] [1] # [ 1,-1]] H.get_block_([2])[0] = 1 T0 = H.get_block_([0]) T0[0, 0] = T0[1, 1] = -1 T0[0, 1] = T0[1, 0] = 1 H.get_block_([-2])[0] = 1 ## create gate: eH = cytnx.linalg.ExpH(H, -dt)