Vector

class psi4.core.Vector

Bases: pybind11_builtins.pybind11_object

Class for creating and manipulating vectors

Attributes Summary

name	The name of the Vector.
np	View without only one irrep
nph	View with irreps.
shape	Shape of the Psi4 data object

Methods Summary

array_interface(self)
dim(self, h)	Returns the dimensions of the vector per irrep h
from_array(arr[, name, dim1, dim2])	Converts a numpy array or list of numpy arrays into a Psi4 Matrix (irreped if list).
from_list(x)
from_serial(json_data)	Converts serialized data to the correct Psi4 data type
get(*args, **kwargs)	Overloaded function.
get_block(self, slice)	Get a vector block
nirrep(self)	Returns the number of irreps
np_read(filename[, prefix])	Reads the data from a NumPy compress file.
np_write([filename, prefix])	Writes the irreped matrix to a NumPy zipped file.
print_out(self)	Prints the vector to the output file
scale(self, sc)	Scales the elements of a vector by sc
set(*args, **kwargs)	Overloaded function.
set_block(self, slice, block)	Set a vector block
to_array([copy, dense])	Converts a Psi4 Matrix or Vector to a numpy array.
to_serial()	Converts an object with a .nph accessor to a serialized dictionary

Attributes Documentation

name

The name of the Vector. Used in printing.

np

View without only one irrep

nph

View with irreps.

shape

Shape of the Psi4 data object

Methods Documentation

array_interface(self: psi4.core.Vector) → list

dim(self: psi4.core.Vector, h: int) → int

Returns the dimensions of the vector per irrep h

classmethod from_array(arr, name='New Matrix', dim1=None, dim2=None)

Converts a numpy array or list of numpy arrays into a Psi4 Matrix (irreped if list).

Parameters:

• arr (array or list of arrays) – Numpy array or list of arrays to use as the data for a new core.Matrix
• name (str) – Name to give the new core.Matrix
• dim1 (list, tuple, or core.Dimension (optional)) – If a single dense numpy array is given, a dimension can be supplied to apply irreps to this array. Note that this discards all extra information given in the matrix besides the diagonal blocks determined by the passed dimension.
• dim2 – Same as dim1 only if using a psi4.core.Dimension object.

Returns:

matrix – Returns the given Psi4 object

Return type:

Matrix or Vector

Notes

This is a generalized function to convert a NumPy array to a Psi4 object

Examples

>>> data = np.random.rand(20)
>>> vector = array_to_matrix(data)

>>> irrep_data = [np.random.rand(2, 2), np.empty(shape=(0,3)), np.random.rand(4, 4)]
>>> matrix = array_to_matrix(irrep_data)
>>> print matrix.rowspi().to_tuple()
(2, 0, 4)

classmethod from_list(x)

classmethod from_serial(json_data)

Converts serialized data to the correct Psi4 data type

get(*args, **kwargs)

Overloaded function.

1. get(self: psi4.core.Vector, m: int) -> float

Returns a single element value located at m

2. get(self: psi4.core.Vector, h: int, m: int) -> float

Returns a single element value located at m in irrep h

get_block(self: psi4.core.Vector, slice: psi4.core.Slice) → psi4.core.Vector

Get a vector block

nirrep(self: psi4.core.Vector) → int

Returns the number of irreps

classmethod np_read(filename, prefix='')

Reads the data from a NumPy compress file.

np_write(filename=None, prefix='')

Writes the irreped matrix to a NumPy zipped file.

Can return the packed data for saving many matrices into the same file.

print_out(self: psi4.core.Vector) → None

Prints the vector to the output file

scale(self: psi4.core.Vector, sc: float) → None

Scales the elements of a vector by sc

set(*args, **kwargs)

Overloaded function.

1. set(self: psi4.core.Vector, m: int, val: float) -> None

Sets a single element value located at m

2. set(self: psi4.core.Vector, h: int, m: int, val: float) -> None

Sets a single element value located at m in irrep h

set_block(self: psi4.core.Vector, slice: psi4.core.Slice, block: psi4.core.Vector) → None

Set a vector block

to_array(copy=True, dense=False)

Converts a Psi4 Matrix or Vector to a numpy array. Either copies the data or simply constructs a view.

Parameters:

• matrix (Matrix or Vector) – Pointers to which Psi4 core class should be used in the construction.
• copy (bool, optional) – Copy the data if True, return a view otherwise
• dense (bool, optional) – Converts irreped Psi4 objects to diagonally blocked dense arrays if True. Returns a list of arrays otherwise.

Returns:

array – Returns either a list of np.array’s or the base array depending on options.

Return type:

ndarray or list of ndarray

Notes

This is a generalized function to convert a Psi4 object to a NumPy array

Examples

>>> data = psi4.Matrix(3, 3)
>>> data.to_array()
[[ 0.  0.  0.]
 [ 0.  0.  0.]
 [ 0.  0.  0.]]

to_serial()

Converts an object with a .nph accessor to a serialized dictionary

array_interface(self: psi4.core.Vector) → list

dim(self: psi4.core.Vector, h: int) → int

Returns the dimensions of the vector per irrep h

classmethod from_array(arr, name='New Matrix', dim1=None, dim2=None)

Converts a numpy array or list of numpy arrays into a Psi4 Matrix (irreped if list).

Parameters:

• arr (array or list of arrays) – Numpy array or list of arrays to use as the data for a new core.Matrix
• name (str) – Name to give the new core.Matrix
• dim1 (list, tuple, or core.Dimension (optional)) – If a single dense numpy array is given, a dimension can be supplied to apply irreps to this array. Note that this discards all extra information given in the matrix besides the diagonal blocks determined by the passed dimension.
• dim2 – Same as dim1 only if using a psi4.core.Dimension object.

Returns:

matrix – Returns the given Psi4 object

Return type:

Matrix or Vector

Notes

This is a generalized function to convert a NumPy array to a Psi4 object

Examples

>>> data = np.random.rand(20)
>>> vector = array_to_matrix(data)

>>> irrep_data = [np.random.rand(2, 2), np.empty(shape=(0,3)), np.random.rand(4, 4)]
>>> matrix = array_to_matrix(irrep_data)
>>> print matrix.rowspi().to_tuple()
(2, 0, 4)

classmethod from_list(x)

classmethod from_serial(json_data)

Converts serialized data to the correct Psi4 data type

get(*args, **kwargs)

Overloaded function.

1. get(self: psi4.core.Vector, m: int) -> float

Returns a single element value located at m

2. get(self: psi4.core.Vector, h: int, m: int) -> float

Returns a single element value located at m in irrep h

get_block(self: psi4.core.Vector, slice: psi4.core.Slice) → psi4.core.Vector

Get a vector block

name

The name of the Vector. Used in printing.

nirrep(self: psi4.core.Vector) → int

Returns the number of irreps

np

View without only one irrep

classmethod np_read(filename, prefix='')

Reads the data from a NumPy compress file.

np_write(filename=None, prefix='')

Writes the irreped matrix to a NumPy zipped file.

Can return the packed data for saving many matrices into the same file.

nph

View with irreps.

print_out(self: psi4.core.Vector) → None

Prints the vector to the output file

scale(self: psi4.core.Vector, sc: float) → None

Scales the elements of a vector by sc

set(*args, **kwargs)

Overloaded function.

1. set(self: psi4.core.Vector, m: int, val: float) -> None

Sets a single element value located at m

2. set(self: psi4.core.Vector, h: int, m: int, val: float) -> None

Sets a single element value located at m in irrep h

set_block(self: psi4.core.Vector, slice: psi4.core.Slice, block: psi4.core.Vector) → None

Set a vector block

shape

Shape of the Psi4 data object

to_array(copy=True, dense=False)

Converts a Psi4 Matrix or Vector to a numpy array. Either copies the data or simply constructs a view.

Parameters:

• matrix (Matrix or Vector) – Pointers to which Psi4 core class should be used in the construction.
• copy (bool, optional) – Copy the data if True, return a view otherwise
• dense (bool, optional) – Converts irreped Psi4 objects to diagonally blocked dense arrays if True. Returns a list of arrays otherwise.

Returns:

array – Returns either a list of np.array’s or the base array depending on options.

Return type:

ndarray or list of ndarray

Notes

This is a generalized function to convert a Psi4 object to a NumPy array

Examples

>>> data = psi4.Matrix(3, 3)
>>> data.to_array()
[[ 0.  0.  0.]
 [ 0.  0.  0.]
 [ 0.  0.  0.]]

to_serial()

Converts an object with a .nph accessor to a serialized dictionary