Vector#

class ubermagutil.typesystem.Vector(name=None, **kwargs)#

Descriptor allowing setting attributes only with vectors (list, tuple, or numpy.ndarray), whose elements are of numbers.Real type.

Parameters:

  • component_type (int or float type, optional) – Type of the vector components. It should be a subset of numbers.Real (int, float).

  • size (int, optional) – Size (length, number of elements) of the vector.

  • positive (bool, optional) – If positive=True, values of all vector elements must be positive (>0).

  • unsigned (bool, optional) – If unsigned=True, values of all vector components must be unsigned (>=0).

  • otherwise (type) – This type would also be accepted if specified. It has priority over other descriptor specification.

Raises:

  • TypeError – If the type(value) is not list, tuple, or numpy.ndarray or if the type of vector components is neither numbers.Real nor expected_type (if passed).

  • ValueError – If vector component value is value < 0 and unsigned=True or value <= 0 and positive=True.

Example

1. Usage of Vector descriptor for defining a three-dimensional vector, whose components myattribute positive integer components.

>>> import ubermagutil.typesystem as ts
...
>>> @ts.typesystem(myattribute=ts.Vector(size=3, component_type=int,
...                                      positive=True))
... class DecoratedClass:
...     def __init__(self, myattribute):
...         self.myattribute = myattribute
...
>>> dc = DecoratedClass(myattribute=(1, 2, 12))
>>> dc.myattribute
(1, 2, 12)
>>> dc.myattribute = (10, 11, 12)  # valid set
>>> dc.myattribute
(10, 11, 12)
>>> dc.myattribute = (11, 12)  # invalid set
Traceback (most recent call last):
    ...
ValueError: ...
>>> dc.myattribute = (0, 1, 2)  # invalid set
Traceback (most recent call last):
    ...
ValueError: ...
>>> dc.myattribute = (1, 3.14, 2)  # invalid set
Traceback (most recent call last):
    ...
TypeError: ...
>>> dc.myattribute  # the value was not affected by invalid sets
(10, 11, 12)

Note

This class was derived from ubermagutil.typesystem.Descriptor and inherits its functionality.

See also

Descriptor

Methods

__delete__

Deleting the decorated class attribute is never allowed and AttributeError is raised.

__dir__

Default dir() implementation.

__eq__

Return self==value.

__repr__

Return repr(self).

__set__

If self.const=True, changing the value of a decorated class attribute after the initial set is not allowed.
__set__(instance, value)#

If self.const=True, changing the value of a decorated class attribute after the initial set is not allowed.

Raises:

AttributeError – If changing the value of a decorated class attribute is attempted.

Example

  1. Changing the value of a constant decorated class attribute.

>>> import ubermagutil.typesystem as ts
...
>>> @ts.typesystem(myattribute=ts.Descriptor(const=True))
... class DecoratedClass:
...     def __init__(self, myattribute):
...         self.myattribute = myattribute
...
>>> dc = DecoratedClass(myattribute="John Doe")
>>> dc.myattribute
'John Doe'
>>> dc.myattribute = 'Jane Doe'
Traceback (most recent call last):
   ...
AttributeError: ...