def plot_state(quantum_state, method='city', filename=None):
"""Plot the quantum state.
Args:
quantum_state (ndarray): statevector or density matrix
representation of a quantum state.
method (str): Plotting method to use.
filename (str): the output file to save the plot as. If specified it
will save and exit and not open up the plot in a new window. If
`bloch` method is used a `-n` will be added to the filename before
the extension for each qubit.
Raises:
VisualizationError: if the input is not a statevector or density
matrix, or if the state is not an multi-qubit quantum state.
"""
# Check if input is a statevector, and convert to density matrix
rho = np.array(quantum_state)
if rho.ndim == 1:
rho = np.outer(rho, np.conj(rho))
# Check the shape of the input is a square matrix
shape = np.shape(rho)
if len(shape) != 2 or shape[0] != shape[1]:
raise VisualizationError("Input is not a valid quantum state.")
# Check state is an n-qubit state
num = int(np.log2(len(rho)))
if 2**num != len(rho):
raise VisualizationError("Input is not a multi-qubit quantum state.")
if method == 'city':
plot_state_city(rho, filename=filename)
elif method == "paulivec":
plot_state_paulivec(rho, filename=filename)
elif method == "qsphere":
plot_state_qsphere(rho, filename=filename)
elif method == "bloch":
orig_filename = filename
for i in range(num):
if orig_filename:
filename_parts = orig_filename.split('.')
filename_parts[-2] += '-%d' % i
filename = '.'.join(filename_parts)
print(filename)
pauli_singles = [
Pauli.pauli_single(num, i, 'X'),
Pauli.pauli_single(num, i, 'Y'),
Pauli.pauli_single(num, i, 'Z')
]
bloch_state = list(
map(lambda x: np.real(np.trace(np.dot(x.to_matrix(), rho))),
pauli_singles))
plot_bloch_vector(bloch_state,
"qubit " + str(i),
filename=filename)
elif method == "wigner":
plot_wigner_function(rho, filename=filename)
elif method == "hinton":
plot_hinton(rho, filename=filename)
def iplot_state(quantum_state, method='city', figsize=None):
"""Plot the quantum state.
Args:
quantum_state (ndarray): statevector or density matrix
representation of a quantum state.
method (str): Plotting method to use.
figsize (tuple): Figure size in inches.
Raises:
VisualizationError: if the input is not a statevector or density
matrix, or if the state is not an multi-qubit quantum state.
"""
warnings.warn(
"iplot_state is deprecated, and will be removed in \
the 0.9 release. Use the iplot_state_ * functions \
instead.", DeprecationWarning)
rho = _validate_input_state(quantum_state)
if method == "city":
iplot_state_city(rho, figsize=figsize)
elif method == "paulivec":
iplot_state_paulivec(rho, figsize=figsize)
elif method == "qsphere":
iplot_state_qsphere(rho, figsize=figsize)
elif method == "bloch":
iplot_bloch_multivector(rho, figsize=figsize)
elif method == "hinton":
iplot_state_hinton(rho, figsize=figsize)
else:
raise VisualizationError('Invalid plot state method.')
def bit_string_index(text):
"""Return the index of a string of 0s and 1s."""
n = len(text)
k = text.count("1")
if text.count("0") != n - k:
raise VisualizationError("s must be a string of 0 and 1")
ones = [pos for pos, char in enumerate(text) if char == "1"]
return lex_index(n, k, ones)
def plot_state(quantum_state, method='city'):
"""Plot the quantum state.
Args:
quantum_state (ndarray): statevector or density matrix
representation of a quantum state.
method (str): Plotting method to use.
Raises:
VisualizationError: if the input is not a statevector or density
matrix, or if the state is not an multi-qubit quantum state.
"""
# Check if input is a statevector, and convert to density matrix
rho = np.array(quantum_state)
if rho.ndim == 1:
rho = np.outer(rho, np.conj(rho))
# Check the shape of the input is a square matrix
shape = np.shape(rho)
if len(shape) != 2 or shape[0] != shape[1]:
raise VisualizationError("Input is not a valid quantum state.")
# Check state is an n-qubit state
num = int(np.log2(len(rho)))
if 2**num != len(rho):
raise VisualizationError("Input is not a multi-qubit quantum state.")
if method == 'city':
plot_state_city(rho)
elif method == "paulivec":
plot_state_paulivec(rho)
elif method == "qsphere":
plot_state_qsphere(rho)
elif method == "bloch":
for i in range(num):
bloch_state = list(
map(lambda x: np.real(np.trace(np.dot(x.to_matrix(), rho))),
pauli_singles(i, num)))
plot_bloch_vector(bloch_state, "qubit " + str(i))
elif method == "wigner":
plot_wigner_function(rho)
def iplot_state(quantum_state, method='city', options=None):
"""Plot the quantum state.
Args:
quantum_state (ndarray): statevector or density matrix
representation of a quantum state.
method (str): Plotting method to use.
options (dict): Plotting settings.
Raises:
VisualizationError: if the input is not a statevector or density
matrix, or if the state is not an multi-qubit quantum state.
"""
# Check if input is a statevector, and convert to density matrix
rho = np.array(quantum_state)
if rho.ndim == 1:
rho = np.outer(rho, np.conj(rho))
# Check the shape of the input is a square matrix
shape = np.shape(rho)
if len(shape) != 2 or shape[0] != shape[1]:
raise VisualizationError("Input is not a valid quantum state.")
# Check state is an n-qubit state
num = int(np.log2(len(rho)))
if 2**num != len(rho):
raise VisualizationError("Input is not a multi-qubit quantum state.")
if method == "city":
iplot_cities(rho, options)
elif method == "paulivec":
iplot_paulivec(rho, options)
elif method == "qsphere":
iplot_qsphere(rho, options)
elif method == "bloch":
iplot_blochsphere(rho, options)
elif method == "hinton":
iplot_hinton(rho, options)
else:
print("Unknown method '" + method + "'.")
def lex_index(n, k, lst):
"""Return the lex index of a combination..
Args:
n (int): the total number of options .
k (int): The number of elements.
lst (list): list
Returns:
int: returns int index for lex order
Raises:
VisualizationError: if length of list is not equal to k
"""
if len(lst) != k:
raise VisualizationError("list should have length k")
comb = list(map(lambda x: n - 1 - x, lst))
dualm = sum([n_choose_k(comb[k - 1 - i], i + 1) for i in range(k)])
return int(dualm)
def plot_state(quantum_state, method='city', filename=None, show=False):
"""Plot the quantum state.
Args:
quantum_state (ndarray): statevector or density matrix
representation of a quantum state.
method (str): Plotting method to use.
filename (str): the output file to save the plot as. If specified it
will save and exit and not open up the plot in a new window. If
`bloch` method is used a `-n` will be added to the filename before
the extension for each qubit.
show (bool): If set to true the rendered image will open in a new
window
Returns:
matplotlib.Figure: The matplotlib.Figure of the visualization
Raises:
VisualizationError: if the input is not a statevector or density
matrix, or if the state is not an multi-qubit quantum state.
"""
# Check if input is a statevector, and convert to density matrix
rho = np.array(quantum_state)
if rho.ndim == 1:
rho = np.outer(rho, np.conj(rho))
# Check the shape of the input is a square matrix
shape = np.shape(rho)
if len(shape) != 2 or shape[0] != shape[1]:
raise VisualizationError("Input is not a valid quantum state.")
# Check state is an n-qubit state
num = int(np.log2(len(rho)))
if 2**num != len(rho):
raise VisualizationError("Input is not a multi-qubit quantum state.")
fig = None
if method == 'city':
fig = plot_state_city(rho, filename=filename, show=show)
elif method == "paulivec":
fig = plot_state_paulivec(rho, filename=filename, show=show)
elif method == "qsphere":
fig = plot_state_qsphere(rho, filename=filename, show=show)
elif method == "bloch":
aspect = float(1 / num)
fig = plt.figure(figsize=plt.figaspect(aspect))
for i in range(num):
ax = fig.add_subplot(1, num, i + 1, projection='3d')
pauli_singles = [
Pauli.pauli_single(num, i, 'X'),
Pauli.pauli_single(num, i, 'Y'),
Pauli.pauli_single(num, i, 'Z')
]
bloch_state = list(
map(lambda x: np.real(np.trace(np.dot(x.to_matrix(), rho))),
pauli_singles))
plot_bloch_vector(bloch_state, "qubit " + str(i), ax=ax)
if filename:
plt.savefig(filename)
elif show:
plt.show()
elif method == "wigner":
fig = plot_wigner_function(rho, filename=filename, show=show)
elif method == "hinton":
fig = plot_hinton(rho, filename=filename, show=show)
return fig