!! Copyright 2010 Fernando M. Cucchietti

!

! This file is part of FortranMPS

!

! FortranMPS is free software: you can redistribute it and/or modify

! it under the terms of the GNU General Public License as published by

! the Free Software Foundation, either version 3 of the License, or

! (at your option) any later version.

!

! FortranMPS is distributed in the hope that it will be useful,

! but WITHOUT ANY WARRANTY; without even the implied warranty of

! MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the

! GNU General Public License for more details.

!

! You should have received a copy of the GNU General Public License

! along with FortranMPS. If not, see <http://www.gnu.org/licenses/>.

test_suite MPSTensor_Class

setup

!Set testing mode

MaxErrorAllowed=CriticalError

end setup

teardown

end teardown

test type_creation_deletion

type(MPSTensor) :: A,B

integer :: spinT=2,BondL=3,BondR=4

A=new_MPSTensor(SpinT,BondL,BondR)

assert_false(WasThereError())

assert_equal(A%delete(),Normal)

call LowerFlag()

B=new_MPSTensor(SpinT,BondL,BondR)

call B%Print('TESTING PRINTING')

assert_equal(B%delete(),Normal)

assert_false(WasThereError())

end test

!

test accesors_work

type(MPSTensor) :: A

integer :: spinT=2,BondL=3,BondR=4

A=new_MPSTensor(SpinT,BondL,BondR)

assert_equal(A%getspin(),SpinT)

assert_equal(A%getDLeft(),BondL)

assert_equal(A%getDRight(),BondR)

assert_equal(A%delete(),Normal)

assert_false(WasThereError())

end test

test CreateATransposedTensor

type(MPSTensor) :: A

type(Tensor3) :: aTensor

integer :: spin=2, bondL=3, bondR=4

integer :: dims(3)

aTensor=new_Tensor(bondR,spin,bondL)

A=new_MPSTensor(aTensor,SecondDimension,ThirdDimension,FirstDimension)

dims=A%GetDimensions()

assert_true( dims .equalvector. [bondL, bondR, spin] )

assert_false(WasThereError())

end test

test RightCanonTensor

!For some reason the output matrix U from SVD is different than the one from Mathematica

! but only in the non-important vectors (where Sigma=0)

!Then, this test is changed to an automatic test that sees if the original tensor can be

!reconstructed by multiplying the canonized tensor with the output matrix

type(MPSTensor) :: TheTensor,CorrectTensor,origTensor

type(Tensor2) :: outputMatrix,correctMatrix

integer,parameter :: spinT=2,DleftT=4, DrightT=3

complex(8) :: data(DleftT,DrightT,spinT)

complex(8) :: matrix(DrightT,DrightT)

complex(8) :: Correct(DleftT,DrightT,spinT)

integer :: i,j,k

!Initialization

forall (i=1:DleftT ,j=1:DrightT, k=1:SpinT) data(i,j,k)=one*(i+(j-1)*DleftT+(k-1)*DrightT)

Correct(:,:,1)=one*Reshape( [-0.234451, -0.271825, -0.309198, -0.346571, -0.625669, -0.440419, &

& -0.255169, -0.0699187, -0.295271, 0.429314, 0.0856099, -0.126573], [DleftT,DrightT])

Correct(:,:,2)=Reshape( [-0.346571, -0.383944, -0.421317, -0.45869, -0.0699187, 0.115331, &

& 0.300581, 0.485831, -0.126573, 0.354249, -0.66644, 0.345686], [DleftT,DrightT])

matrix(:,:)=Reshape( [-12.1367, 2.9496, 0., -23.227, 0.712199, 0., &

& -34.3173, -1.5252, 0.], [DrightT,DrightT] )

TheTensor=new_MPSTensor(data(:,:,1),data(:,:,2))

origTensor=TheTensor

!CorrectTensor=new_MPSTensor(Correct(:,:,1),Correct(:,:,2))

outputMatrix=RightCanonize(TheTensor) ! C=A%LCanonize()

correctMatrix=new_Tensor(matrix)

CorrectTensor=MPSTensor_times_matrix(TheTensor,outputMatrix)

assert_equal_within(outputMatrix.absdiff.correctMatrix, 0.0d0, 1.0e-4)

assert_equal_within(OrigTensor.absdiff.CorrectTensor, 0.0d0, 1.0e-5)

end test

test LeftCanonTensor

!For some reason the output matrix U from SVD is different than the one from Mathematica

! but only in the non-important vectors (where Sigma=0)

!Then, this test is changed to an automatic test that sees if the original tensor can be

!reconstructed by multiplying the canonized tensor with the output matrix

type(MPSTensor) :: TheTensor,ReconstructedTensor,origTensor

type(Tensor2) :: outputMatrix

integer,parameter :: spinT=2,DleftT=3, DrightT=4

complex(8) :: data(DleftT,DrightT,spinT)

integer :: i,j,k

!Initialization

forall (i=1:DleftT ,j=1:DrightT, k=1:SpinT) data(i,j,k)=one*(i+10*j+II*k)

TheTensor=new_MPSTensor(data(:,:,1),data(:,:,2))

origTensor=TheTensor

outputMatrix=LeftCanonize(TheTensor) ! C=A%LCanonize()

ReconstructedTensor=matrix_times_MPSTensor(outputMatrix,TheTensor)

assert_equal_within(OrigTensor.absdiff.ReconstructedTensor, 0.0d0, 1.0e-5)

end test

test ApplyOperator

type(MPSTensor) :: A,B,C

integer,parameter :: DleftT=4, DrightT=3,spinT=2

complex(8) :: data(DleftT,DrightT,spinT)

complex(8) :: Correct(DleftT,DrightT,spinT)

integer error

!Initialization

data(:,:,1)=one*Reshape( [-0.120802, -0.736476, 0.639716, -0.0536866, -0.304505, -0.320898, &

& -0.325939, -0.200223, -0.488209, 0.0946794, 0.17894, 0.76573], [DleftT,DrightT])

data(:,:,2)=one*Reshape( [-0.258579, -0.424792, -0.512473, -0.130085, -0.442283, -0.00921493, &

& -0.298086, 0.183901, -0.625986, 0.406363, 0.317842, -0.565636], [DleftT,DrightT])

Correct(:,:,1)=data(:,:,1)

Correct(:,:,2)=(-1.0d0)*data(:,:,2)

A=new_MPSTensor(data(:,:,1),data(:,:,2))

B=new_MPSTensor(Correct(:,:,1),Correct(:,:,2))

C=A.Apply.PauliSigma(3)

assert_equal_within(B.absdiff.C, 0.0d0, 1.0e-5)

assert_false(WasThereError())

end test

!

!

!

!

!test RightCanonTensor

! type(MPSTensor) :: A,B,C,D

! integer,parameter :: DleftT=4, DrightT=3

! complex(8) :: data(DleftT,DrightT,spinT)

! complex(8) :: matrix(DleftT,DleftT,1)

! complex(8) :: Correct(DleftT,DrightT,spinT)

! integer :: i,j,k

!

! !Initialization

! forall (i=1:DleftT ,j=1:DrightT, k=1:SpinT) data(i,j,k)=one*(i+(j-1)*DleftT+(k-1)*DrightT)

! Correct(:,:,1)=one*Reshape( [-0.120802, -0.736476, 0.639716, -0.0536866, -0.304505, -0.320898, &

! & -0.325939, -0.200223, -0.488209, 0.0946794, 0.17894, 0.76573], [DleftT,DrightT])

! Correct(:,:,2)=one*Reshape( [-0.258579, -0.424792, -0.512473, -0.130085, -0.442283, -0.00921493, &

! & -0.298086, 0.183901, -0.625986, 0.406363, 0.317842, -0.565636], [DleftT,DrightT])

! matrix(:,:,1)=one*Reshape ( [-18.1216, -20.362, -22.6023, -24.8427, 1.61461, 0.624272, -0.366067, &

! & -1.35641, 0., 0., 0., 0., 0., 0., 0., 0.], [DleftT,DleftT] )

! A=new_MPSTensor(SpinT,DleftT,DrightT,data)

! B=new_MPSTensor(SpinT,DleftT,DrightT,Correct)

! C=Right_Canonize_MPSTensor(A)!C=A%RCanonize()

! D=new_MPSTensor(MatrixSpin,DleftT,DleftT,matrix)

! assert_equal_within(A.absdiff.B, 0.0d0, 1.0e-5)

! assert_equal_within(C.absdiff.D, 0.0d0, 1.0e-4)

! assert_equal(A%delete(),Normal)

! assert_equal(B%delete(),Normal)

! assert_equal(C%delete(),Normal)

! assert_equal(D%delete(),Normal)

! assert_false(WasThereError())

!end test

!

!

end test_suite

! print *,shape(data(:,:,:))

! print *,'And now'

! print *,shape(transpose(data(:,:,:)))

!! print *,'And finally'

! print *,shape(reshape(data,[DLeftT,spinT*DrightT]))

! assert_true(.true.)