openmc.Halfspace

class openmc.Halfspace(surface, side)[source]

A positive or negative half-space region.

A half-space is either of the two parts into which a two-dimension surface divides the three-dimensional Euclidean space. If the equation of the surface is \(f(x,y,z) = 0\), the region for which \(f(x,y,z) < 0\) is referred to as the negative half-space and the region for which \(f(x,y,z) > 0\) is referred to as the positive half-space.

Instances of Halfspace are generally not instantiated directly. Rather, they can be created from an existing Surface through the __neg__ and __pos__ operators, as the following example demonstrates:

>>> sphere = openmc.Sphere(surface_id=1, r=10.0)
>>> inside_sphere = -sphere
>>> outside_sphere = +sphere
>>> type(inside_sphere)
<class 'openmc.surface.Halfspace'>
Parameters
  • surface (openmc.Surface) – Surface which divides Euclidean space.

  • side ({'+', '-'}) – Indicates whether the positive or negative half-space is used.

Variables
  • surface (openmc.Surface) – Surface which divides Euclidean space.

  • side ({'+', '-'}) – Indicates whether the positive or negative half-space is used.

  • bounding_box (openmc.BoundingBox) – Lower-left and upper-right coordinates of an axis-aligned bounding box

clone(memo=None)[source]

Create a copy of this halfspace, with a cloned surface with a unique ID.

Parameters

memo (dict or None) – A nested dictionary of previously cloned objects. This parameter is used internally and should not be specified by the user.

Returns

clone – The clone of this halfspace

Return type

openmc.Halfspace

get_surfaces(surfaces=None)[source]

Returns the surface that this is a halfspace of.

Parameters

surfaces (dict, optional) – Dictionary mapping surface IDs to openmc.Surface instances

Returns

surfaces – Dictionary mapping surface IDs to openmc.Surface instances

Return type

dict

remove_redundant_surfaces(redundant_surfaces)[source]

Recursively remove all redundant surfaces referenced by this region

Parameters

redundant_surfaces (dict) – Dictionary mapping redundant surface IDs to surface IDs for the openmc.Surface instances that should replace them.

rotate(rotation, pivot=(0.0, 0.0, 0.0), order='xyz', inplace=False, memo=None)[source]

Rotate surface by angles provided or by applying matrix directly.

New in version 0.12.

Parameters
  • rotation (3-tuple of float, or 3x3 iterable) – A 3-tuple of angles \((\phi, \theta, \psi)\) in degrees where the first element is the rotation about the x-axis in the fixed laboratory frame, the second element is the rotation about the y-axis in the fixed laboratory frame, and the third element is the rotation about the z-axis in the fixed laboratory frame. The rotations are active rotations. Additionally a 3x3 rotation matrix can be specified directly either as a nested iterable or array.

  • pivot (iterable of float, optional) – (x, y, z) coordinates for the point to rotate about. Defaults to (0., 0., 0.)

  • order (str, optional) – A string of ‘x’, ‘y’, and ‘z’ in some order specifying which rotation to perform first, second, and third. Defaults to ‘xyz’ which means, the rotation by angle \(\phi\) about x will be applied first, followed by \(\theta\) about y and then \(\psi\) about z. This corresponds to an x-y-z extrinsic rotation as well as a z-y’-x’’ intrinsic rotation using Tait-Bryan angles \((\phi, \theta, \psi)\).

  • inplace (bool) – Whether or not to return a new instance of Surface or to modify the coefficients of this Surface in place. Defaults to False.

  • memo (dict or None) – Dictionary used for memoization

Returns

Translated half-space

Return type

openmc.Halfspace

translate(vector, inplace=False, memo=None)[source]

Translate half-space in given direction

Parameters
  • vector (iterable of float) – Direction in which region should be translated

  • memo (dict or None) – Dictionary used for memoization

Returns

Translated half-space

Return type

openmc.Halfspace