def set_tensornetwork_backend(backend: Optional[str] = None) -> None:
"""
set the runtime backend of tensornetwork
:param backend: numpy, tensorflow, jax, pytorch
:return:
"""
if not backend:
backend = get_default_backend()
backend_obj = get_backend(backend)
for module in modules:
if module in sys.modules:
setattr(sys.modules[module], "backend", backend_obj)
tn.set_default_backend(backend)
def test_set_default(backend):
tensornetwork.set_default_backend(backend)
assert tensornetwork.config.default_backend == backend
net = tensornetwork.TensorNetwork()
assert net.backend.name == backend
from tensornetwork.block_sparse.charge import U1Charge
from tensornetwork.block_sparse.index import Index
from tensornetwork.block_sparse import BlockSparseTensor as BT
from tensornetwork.block_sparse import linalg as BLA
from tensornetwork.block_sparse import initialization as BI
from tensornetwork.block_sparse.caching import set_caching_status, clear_cache
# tensornetwork and block_sparse modules
from eigh import eigh
from helper_functs import orthog, trunct_eigh, expand_dims, orthog_sym, eye_sym
from sym_link_networks import (LiftHam, LowerDensity, RightLink, LeftLink,
TopLink, CenterLink)
# from link_networks import CenterLink
from binaryMERA import binaryMERA
tn.set_default_backend('symmetric')
set_caching_status(True)
clear_cache()
# set simulation parameters
chi_b = 4
chi = 4
chi_p = 4
chi_m = 16
n_levels = 3
n_iterations = 1000
n_sites = 3 * (2**(n_levels + 1))
left_on = 1
right_on = 1
center_on = 1
import numpy as np
#import tensorflow as tf
# tf.enable_v2_behavior()
import tensornetwork as tn
tn.set_default_backend("numpy")
class TSpinSq(object):
"""Generate the vacuum S^2 operator."""
def __init__(self, n_hole_states, n_particle_states, ref=[], s=0.5):
"""Class constructor. Instantiate PairingHamiltonian2B object.
Arguments:
n_hole_states -- number of holes states in the single particle basis
n_particle_states -- number of particles states in the single particle basis
Keyword arguments:
ref -- the reference state. must match dimensions imposed by arugments (default: [1,1,1,1,0,0,0,0])
d -- the energy level spacing (default: 1.0)
g -- the pairing strength (default: 0.5)
pb -- strength of the pair-breaking term (operates in double particle basis) (default: 0.0)"""
self._s = s
if ref == []:
self._reference = np.append(
np.ones(n_hole_states, dtype=np.float32),
np.zeros(n_particle_states, dtype=np.float32))
else:
self._reference = np.asarray(ref, dtype=np.float32)
def test_set_default(backend):
tn.set_default_backend(backend)
assert _default_backend_stack.default_backend == backend
a = tn.Node(np.eye(2))
assert a.backend.name == backend
from tensorflow.python.framework.ops import disable_eager_execution
from TNModel.utils import *
import TNModel.tf_model as tf_model
import tensornetwork as tn
import tensorflow as tf
import numpy as np
import os
os.environ['TF_DISABLE_MLC'] = '1'
# If you want to run in eager mode, just comment those two lines.
disable_eager_execution()
tn.set_default_backend('tensorflow')
# HyperParams
hyper_params = {
'rank': 28 * 28,
'phys_dim': 10,
'bond_dim': 2,
'labels': 10,
'string_cnt': 4, # for 1d-sbs only
'sbs_op':
'mean', # mean or prod , alternative choice for 1d-sbs contraction
'model': 'peps', # mps (finished) or 1d-sbs (half-working)
# vectorized_map is only supported in part of the machines.
'vectorized': True,
'batch_size': 16,
'max_singular_values': 64
}
if __name__ == '__main__':
from mpl_toolkits import mplot3d
import numpy as np
import matplotlib.pyplot as plt
import tensorflow as tf
# tf.enable_v2_behavior()
# Import tensornetwork
import tensornetwork as tn
# Settting backend to tensorflow otherwise numpy is usedB
tn.set_default_backend("tensorflow")
class TNLayer(tf.keras.layers.Layer):
def __init__(self):
super(TNLayer, self).__init__()
# Creating variables for the layer.
self.a_var = tf.Variable(tf.random.normal(shape=(8, 8, 2),
stddev=1.0 / 16.0),
name="a",
trainable=True)
self.b_var = tf.Variable(tf.random.normal(shape=(8, 8, 2),
stddev=1.0 / 16.0),
name="b",
trainable=True)
self.bias = tf.Variable(tf.zeros(shape=(8, 8)),
name="bias",
trainable=True)
def call(self, inputs):
# Define the contraction
def test_contextmanager_BaseBackend():
tn.set_default_backend("pytorch")
a = tn.Node(np.ones((10, )))
with tn.DefaultBackend(a.backend):
b = tn.Node(np.ones((10, )))
assert b.backend.name == "pytorch"
def test_set_default_backend_value_error():
tn.set_default_backend("pytorch")
with pytest.raises(ValueError,
match="Item passed to set_default_backend "
"must be Text or BaseBackend"):
tn.set_default_backend(-1) # pytype: disable=wrong-arg-types
def test_contextmanager_default_backend():
tn.set_default_backend("pytorch")
with tn.DefaultBackend("numpy"):
assert _default_backend_stack.default_backend == "pytorch"
def test_contextmanager_interruption():
tn.set_default_backend("pytorch")
with pytest.raises(AssertionError):
with tn.DefaultBackend("numpy"):
tn.set_default_backend("tensorflow")
for jdx in range(num_batch):
f(*args)
acc += time.time() - start
return acc / num_iter
def foo(a, b):
node1 = tn.Node(a)
node2 = tn.Node(b)
node1[1] ^ node2[0]
return tn.contract_between(node1, node2)
def run(n, num_iter, num_batch):
a, b = np.random.randn(2, n, n)
nops = 2 * n**3 / 1e9
elapsed = benchmark(num_iter, num_batch, foo, a, b)
print(n, " ", nops / elapsed)
if __name__ == "__main__":
tn.set_default_backend(sys.argv[1])
for i in range(4096, 512, -256):
run(i, 10, 1)
for i in range(512, 64, -32):
run(i, 50, 1000)
for i in range(64, 16, -1):
run(i, 50, 1000)
def reset_default_backend():
tensornetwork.set_default_backend("numpy")
yield
tensornetwork.set_default_backend("numpy")
A[N - 1])
A[N - 1] = B
mps.tensors = A
print("")
##### -ZZ+hZ+gX model #############
#######################################
##### Set bond dimensions and simulation options
h = 0.7
g = 1.05
tn.set_default_backend('jax')
print('H = - ZZ + hZ + gX')
print('g = {g}'.format(g=g))
print('h = {h}\n'.format(h=h))
num = 0
Narray = [10]
prec = 1E-4
Dinit = 8
for N in Narray:
print('Length of the chain = {N}\n'.format(N=N))
"""
DMRG for XXZ model.
"""
from typing import Type, Text
import tensornetwork as tn
import numpy as np
tn.set_default_backend('pytorch')
def initialize_spin_mps(N: int, D: int, dtype: Type[np.number]):
return tn.FiniteMPS.random([2] * N, [D] * (N - 1), dtype=dtype)
def initialize_XXZ_mpo(Jz: np.ndarray, Jxy: np.ndarray, Bz: np.ndarray,
dtype: Type[np.number]):
return tn.FiniteXXZ(Jz, Jxy, Bz, dtype=dtype)
def run_twosite_dmrg(N: int, D: int, dtype: Type[np.number], Jz: np.ndarray,
Jxy: np.ndarray, Bz: np.ndarray, num_sweeps: int):
mps = initialize_spin_mps(N, 32, dtype)
mpo = initialize_XXZ_mpo(Jz, Jxy, Bz, dtype)
dmrg = tn.FiniteDMRG(mps, mpo)
result = dmrg.run_two_site(max_bond_dim=D,
num_sweeps=num_sweeps,
num_krylov_vecs=10,
verbose=1)
return result, mps
def test_bad_backend_name():
with pytest.raises(ValueError, match="Backend 'BAD_NAME' was not found."):
tn.set_default_backend("BAD_NAME")
...
[r_{1,n}, r_{2,n}, ..., d_n]]
The diagonal entries here are precisely the input dimensions for each of
the core tensors, while the symmetric nature of the matrix is necessary
for different cores to contract with each other.
Besides the above matrix format, the ranks are also sometimes specified
in the following upper-triangular format:
[[r_{1,2}, r_{1,3}, ..., r_{1,n}], [r_{2,3}, ..., r_{2,n}], ...
..., [r_{n-2,n-1}, r_{n-2,n}], [r_{n-1,n}]]
"""
# Set global defaults
tn.set_default_backend("pytorch")
torch.set_default_tensor_type(torch.DoubleTensor)
def continuous_optim(tensor_list,
train_data,
loss_fun,
epochs=10,
val_data=None,
other_args=dict()):
"""
Train a tensor network using gradient descent on input dataset
Args:
tensor_list: List of tensors encoding the network being trained
train_data: The data used to train the network
def backend_tensorflow():
tn.set_default_backend("tensorflow")
yield
tn.set_default_backend("numpy")
