anastruct.fem.system

Classes

SystemElements

Modelling any structure starts with an object of this class.

Functions

_negative_index_to_id(→ int)

Convert a negative index to a positive index. (That is, allowing the Pythonic negative indexing)

Module Contents

class anastruct.fem.system.SystemElements(figsize: Tuple[float, float] | None = (12, 8), EA: float = 15000.0, EI: float = 5000.0, load_factor: float = 1.0, mesh: int = 50, invert_y_loads: bool = True)[source]

Modelling any structure starts with an object of this class.

Attributes:

EA: Standard axial stiffness of elements, default=15,000 EI: Standard bending stiffness of elements, default=5,000 figsize: (tpl) Matplotlibs standard figure size element_map: (dict) Keys are the element ids, values are the element objects node_map: (dict) Keys are the node ids, values are the node objects. node_element_map: (dict) maps node ids to element objects. loads_point: (dict) Maps node ids to point loads. loads_q: (dict) Maps element ids to q-loads. loads_moment: (dict) Maps node ids to moment loads. loads_dead_load: (set) Element ids that have a dead load applied.

Methods:

add_element: Add a new element to the structure. add_element_grid: Add multiple elements based upon sequential x and y coordinates. add_sequential_elements: Add multiple elements based upon any number of sequential points. add_multiple_elements: Add multiple elements defined by the first and the last point. add_truss_element: Add a new truss element (an element that only has axial force) to the structure. add_support_hinged: Add a hinged support to a node. add_support_fixed: Add a fixed support to a node. add_support_roll: Add a roll support to a node. add_support_rotational: Add a rotational support to a node. add_support_spring: Add a spring support to a node. insert_node: Insert a node into an existing structure. solve: Compute the results of current model. validate: Validate the current model.

post_processor[source]
plotter[source]
plot_values[source]
EA = 15000.0[source]
EI = 5000.0[source]
figsize = (12, 8)[source]
orientation_cs = -1[source]
element_map: Dict[int, anastruct.fem.elements.Element][source]
node_map: Dict[int, anastruct.fem.node.Node][source]
node_element_map: Dict[int, List[anastruct.fem.elements.Element]][source]
system_spring_map: Dict[int, float][source]
_remainder_indexes: List[int] = [][source]
supports_fixed: List[anastruct.fem.node.Node] = [][source]
supports_hinged: List[anastruct.fem.node.Node] = [][source]
supports_rotational: List[anastruct.fem.node.Node] = [][source]
internal_hinges: List[anastruct.fem.node.Node] = [][source]
supports_roll: List[anastruct.fem.node.Node] = [][source]
supports_spring_x: List[Tuple[anastruct.fem.node.Node, bool]] = [][source]
supports_spring_y: List[Tuple[anastruct.fem.node.Node, bool]] = [][source]
supports_spring_z: List[Tuple[anastruct.fem.node.Node, bool]] = [][source]
supports_roll_direction: List[Literal[1, 2]] = [][source]
inclined_roll: Dict[int, float][source]
supports_roll_rotate: List[bool] = [][source]
supports_spring_args: List[tuple] = [][source]
loads_point: Dict[int, Tuple[float, float]][source]
loads_q: Dict[int, List[Tuple[float, float]]][source]
loads_moment: Dict[int, float][source]
loads_dead_load: Set[int][source]
reaction_forces: Dict[int, anastruct.fem.node.Node][source]
non_linear = False[source]
non_linear_elements: Dict[int, Dict[Literal[1, 2], float]][source]
buckling_factor: float | None = None[source]
_previous_point[source]
load_factor = 1.0[source]
count = 0[source]
system_matrix: numpy.ndarray | None = None[source]
system_force_vector: numpy.ndarray | None = None[source]
system_displacement_vector: numpy.ndarray | None = None[source]
shape_system_matrix: int | None = None[source]
reduced_force_vector: numpy.ndarray | None = None[source]
reduced_system_matrix: numpy.ndarray | None = None[source]
_vertices: Dict[anastruct.vertex.Vertex, int][source]
property id_last_element: int[source]

ID of the last element added to the structure

Returns:

int: ID of the last element added to the structure

property id_last_node: int[source]

ID of the last node added to the structure

Returns:

int: ID of the last node added to the structure

add_sequential_elements(location: Sequence[anastruct._types.VertexLike], EA: List[float] | numpy.ndarray | float | None = None, EI: List[float] | numpy.ndarray | float | None = None, g: List[float] | numpy.ndarray | float | None = None, mp: anastruct._types.MpType | None = None, spring: anastruct._types.Spring | None = None, **kwargs: dict) None[source]

Add multiple elements based upon any number of sequential points.

Args:
location (Sequence[VertexLike]): Sequence of points

that define the elements.

EA (Optional[Union[List[float], np.ndarray, float]], optional): Axial stiffnesses. Defaults to None. EI (Optional[Union[List[float], np.ndarray, float]], optional): Bending stiffnesses. Defaults to None. g (Optional[Union[List[float], np.ndarray, float]], optional): Self-weights. Defaults to None. mp (Optional[MpType], optional): Maximum plastic moment capacities for all elements. Defaults to None. spring (Optional[Spring], optional): Springs for all elements. Defaults to None.

Raises:

FEMException: The mp parameter should be a dictionary.

add_element_grid(x: List[float] | numpy.ndarray, y: List[float] | numpy.ndarray, EA: List[float] | numpy.ndarray | float | None = None, EI: List[float] | numpy.ndarray | float | None = None, g: List[float] | numpy.ndarray | float | None = None, mp: anastruct._types.MpType | None = None, spring: anastruct._types.Spring | None = None, **kwargs: dict) None[source]

Add multiple elements based upon sequential x and y coordinates.

Args:

x (Union[List[float], np.ndarray]): X coordinates of the grid y (Union[List[float], np.ndarray]): Y coordinates of the grid EA (Optional[Union[List[float], np.ndarray, float]], optional): Axial stiffnesses. Defaults to None. EI (Optional[Union[List[float], np.ndarray, float]], optional): Bending stiffnesses. Defaults to None. g (Optional[Union[List[float], np.ndarray, float]], optional): Self-weights. Defaults to None. mp (Optional[MpType], optional): Maximum plastic moment capacities for all elements. Defaults to None. spring (Optional[Spring], optional): Springs for all elements. Defaults to None.

Raises:

FEMException: x and y should have the same length.

add_truss_element(location: Sequence[anastruct._types.VertexLike] | anastruct._types.VertexLike, EA: float | None = None, **kwargs: dict) int[source]

Add a new truss element (an element that only has axial force) to the structure Example:

location=[[x, y], [x, y]]
location=[Vertex, Vertex]
location=[x, y]
location=Vertex
Args:
location (Union[Sequence[VertexLike], VertexLike]):

The two nodes of the element or the next node of the element.

EA (Optional[float], optional): Axial stiffness of the new element. Defaults to None.

Returns:

int: ID of the new element

add_element(location: Sequence[anastruct._types.VertexLike] | anastruct._types.VertexLike, EA: float | None = None, EI: float | None = None, g: float = 0, mp: anastruct._types.MpType | None = None, spring: anastruct._types.Spring | None = None, **kwargs: Any) int[source]

Add a new general element (an element with axial and lateral force) to the structure Example:

location=[[x, y], [x, y]]
location=[Vertex, Vertex]
location=[x, y]
location=Vertex

mp={1: 210e3, 2: 180e3}

spring={1: k, 2: k}

# Set a hinged node:
spring={1: 0}
Args:
location (Union[Sequence[VertexLike], VertexLike]):

The two nodes of the element or the next node of the element

EA (Optional[float], optional): Axial stiffness of the new element. Defaults to None. EI (Optional[float], optional): Bending stiffness of the new element. Defaults to None. g (float, optional): Self-weight of the new element. Defaults to 0. mp (Optional[MpType], optional): Maximum plastic moment of each end node. Keys are integers representing

the nodes. Values are the bending moment capacity. Defaults to None.

spring (Optional[Spring], optional): Rotational spring or hinge (k=0) of each end node.

Keys are integers representing the nodes. Values are the bending moment capacity. Defaults to None.

Optional Keyword Args:

element_type (ElementType): “general” (axial and lateral force) or “truss” (axial force only) steelsection (str): Steel section name like IPE 300 orient (OrientAxis): Steel section axis for moment of inertia - ‘y’ and ‘z’ possible b (float): Width of generic rectangle section h (float): Height of generic rectangle section d (float): Diameter of generic circle section sw (bool): If true self weight of section is considered as dead load E (float): Modulus of elasticity for section material gamma (float): Weight of section material per volume unit. [kN/m3] / [N/m3]s

Returns:

int: ID of the new element

remove_element(element_id: int) None[source]

Remove an element from the structure.

Args:

element_id (int): ID of the element to remove

add_multiple_elements(location: Sequence[anastruct._types.VertexLike] | anastruct._types.VertexLike, n: int | None = None, dl: float | None = None, EA: float | None = None, EI: float | None = None, g: float = 0, mp: anastruct._types.MpType | None = None, spring: anastruct._types.Spring | None = None, **kwargs: Any) List[int][source]

Add multiple elements defined by the first and the last point.

Example:

last={'EA': 1e3, 'mp': 290}
Args:
location (Union[Sequence[VertexLike], VertexLike]):

The two nodes of the element or the next node of the element.

n (Optional[int], optional): Number of elements to add between the first and last nodes. Defaults to None. dl (Optional[float], optional): Length of sub-elements to add between the first and last nodes.

Length will be rounded down if necessary such that all sub-elements will have the same length. Defaults to None.

EA (Optional[float], optional): Axial stiffness. Defaults to None. EI (Optional[float], optional): Bending stiffness. Defaults to None. g (float, optional): Self-weight. Defaults to 0. mp (Optional[MpType], optional): Maximum plastic moment capacity at ends of element. Defaults to None. spring (Optional[Spring], optional): Rotational springs or hinges (k=0) at ends of element.

Defaults to None.

Optional Keyword Args:

element_type (ElementType): “general” (axial and lateral force) or “truss” (axial force only) first (dict): Different arguments for the first element last (dict): Different arguments for the last element steelsection (str): Steel section name like IPE 300 orient (OrientAxis): Steel section axis for moment of inertia - ‘y’ and ‘z’ possible b (float): Width of generic rectangle section h (float): Height of generic rectangle section d (float): Diameter of generic circle section sw (bool): If true self weight of section is considered as dead load E (float): Modulus of elasticity for section material gamma (float): Weight of section material per volume unit. [kN/m3] / [N/m3]s

Raises:

FEMException: One, and only one, of n and dl should be passed as argument.

Returns:

List[int]: IDs of the new elements

insert_node(element_id: int, location: anastruct._types.VertexLike | None = None, factor: float | None = None) dict[str, int][source]

Insert a node into an existing structure. This can be done by adding a new Vertex at any given location, or by setting a factor of the elements length. E.g. if you want a node at 40% of the elements length, you pass factor = 0.4.

Args:

element_id (int): Id number of the element in which you want to insert the node location (Optional[VertexLike], optional): Location in which to insert the node.

Defaults to None.

factor (Optional[float], optional): Fraction of distance from start to end of elmeent on which to

divide the element. Must be between 0 and 1. Defaults to None.

Returns:
dict[str, int]: Dictionary with keys:

‘new_node_id’: ID of the newly created node ‘new_element_id1’: ID of the first new element created ‘new_element_id2’: ID of the second new element created ‘old_element_id’: ID of the old element that was split

insert_node_old(element_id: int, location: anastruct._types.VertexLike | None = None, factor: float | None = None) None[source]

Insert a node into an existing structure. This can be done by adding a new Vertex at any given location, or by setting a factor of the elements length. E.g. if you want a node at 40% of the elements length, you pass factor = 0.4.

Note: this method completely rebuilds the SystemElements object and is therefore slower then building a model with add_element methods.

Args:

element_id (int): Id number of the element in which you want to insert the node location (Optional[VertexLike], optional): Location in which to insert the node.

Defaults to None.

factor (Optional[float], optional): Fraction of distance from start to end of elmeent on which to

divide the element. Must be between 0 and 1. Defaults to None.

solve(force_linear: bool = False, verbosity: int = 0, max_iter: int = 200, geometrical_non_linear: int = False, **kwargs: Any) numpy.ndarray[source]

Compute the results of current model.

Args:
force_linear (bool, optional): Force a linear calculation, even when the system has non-linear nodes.

Defaults to False.

verbosity (int, optional): Log calculation outputs (0), or silence (1). Defaults to 0. max_iter (int, optional): Maximum allowed iterations. Defaults to 200. geometrical_non_linear (int, optional): Calculate second order effects and determine the buckling factor.

Defaults to False.

Optional Keyword Args:

naked (bool): Whether or not to run the solve function without doing post processing. discretize_kwargs (dict): When doing a geometric non linear analysis you can reduce or

increase the number of elements created that are used for determining the buckling_factor

Raises:
FEMException: The eigenvalues of the stiffness matrix are non zero, which indicates an unstable structure.

Check your support conditions

Returns:

np.ndarray: Displacements vector.

validate(min_eigen: float = 1e-09) bool[source]

Validate the stability of the stiffness matrix.

Args:
min_eigen (float, optional): Minimum value of the eigenvalues of the stiffness matrix. This value

should be close to zero. Defaults to 1e-9.

Returns:

bool: True if the structure is stable, False if not.

add_support_hinged(node_id: int | Sequence[int]) None[source]

Model a hinged support at a given node.

Args:

node_id (Union[int, Sequence[int]]): Represents the nodes ID

add_support_rotational(node_id: int | Sequence[int]) None[source]

Model a rotational support at a given node.

Args:

node_id (Union[int, Sequence[int]]): Represents the nodes ID

add_internal_hinge(node_id: int | Sequence[int]) None[source]

Model a internal hinge at a given node. This may alternatively be done by setting a spring restraint to zero ({1: 0} or {2: 0}). The effect is the same, though this function may be easier to use.

Args:

node_id (Union[int, Sequence[int]]): Represents the nodes ID

add_support_roll(node_id: Sequence[int] | int, direction: Sequence[anastruct._types.SupportDirection] | anastruct._types.SupportDirection = 'x', angle: Sequence[float | None] | float | None = None, rotate: Sequence[bool] | bool = True) None[source]

Add a rolling support at a given node.

Args:

node_id (Union[Sequence[int], int]): Represents the nodes ID direction (Union[Sequence[SupportDirection], SupportDirection], optional): Represents the direction

that is free (“x”, “y”, “1”, or “2”). Defaults to “x”.

angle (Union[Sequence[Optional[float]], Optional[float]], optional): Angle in degrees relative to

global x-axis. If angle is given, the support will be inclined. Defaults to None.

rotate (Union[Sequence[bool], bool], optional): If set to False, rotation at the roller will also

be restrianed. Defaults to True.

Raises:

FEMException: Invalid direction, if the direction parameter is invalid

add_support_fixed(node_id: Sequence[int] | int) None[source]

Add a fixed support at a given node.

Args:

node_id (Union[Sequence[int], int]): Represents the nodes ID

add_support_spring(node_id: Sequence[int] | int, translation: Sequence[anastruct._types.AxisNumber] | anastruct._types.AxisNumber, k: Sequence[float] | float, roll: Sequence[bool] | bool = False) None[source]

Add a spring support at a given node.

Args:

node_id (Union[Sequence[int], int]): Represents the nodes ID translation (Union[Sequence[AxisNumber], AxisNumber]): Represents the prevented translation or rotation.

1 = translation in x, 2 = translation in y, 3 = rotation about z

k (Union[Sequence[float], float]): Stiffness of the spring roll (Union[Sequence[bool], bool], optional): If set to True, only the translation of the

spring is controlled. Defaults to False.

q_load(q: float | Sequence[float], element_id: int | Sequence[int], direction: anastruct._types.LoadDirection | Sequence[anastruct._types.LoadDirection] = 'element', rotation: float | Sequence[float] | None = None, q_perp: float | Sequence[float] | None = None) None[source]

Apply a q-load (distributed load) to an element.

Args:

q (Union[float, Sequence[float]]): Value of the q-load element_id (Union[int, Sequence[int]]): The element ID to which to apply the load direction (Union["LoadDirection", Sequence["LoadDirection"]], optional):

“element”, “x”, “y”, “parallel”, or “perpendicular”. Defaults to “element”.

rotation (Optional[Union[float, Sequence[float]]], optional): Rotate the force clockwise.

Rotation is in degrees. Defaults to None.

q_perp (Optional[Union[float, Sequence[float]]], optional): Value of any q-load perpendicular

to the indicated direction/rotatione. Defaults to None.

Raises:

FEMException: _description_

point_load(node_id: int | Sequence[int], Fx: float | Sequence[float] = 0.0, Fy: float | Sequence[float] = 0.0, rotation: float | Sequence[float] = 0.0, Fz: float | Sequence[float] | None = None) None[source]

Apply a point load to a node.

Args:

node_id (Union[int, Sequence[int]]): The node ID to which to apply the load Fx (Union[float, Sequence[float]], optional): Force in the global X direction. Defaults to 0.0. Fy (Union[float, Sequence[float]], optional): Force in the global Y direction. Defaults to 0.0. rotation (Union[float, Sequence[float]], optional): Rotate the force clockwise by the given

angle in degrees. Defaults to 0.0.

Raises:

FEMException: Point loads may not be placed at the location of inclined roller supports

moment_load(node_id: int | Sequence[int], Tz: float | Sequence[float] = 0.0, Ty: float | Sequence[float] | None = None) None[source]

Apply a moment load to a node.

Args:

node_id (Union[int, Sequence[int]]): The node ID to which to apply the load Tz (Union[float, Sequence[float]]): Moment load (about the global Y direction) to apply

show_structure(verbosity: int, scale: float, offset: Tuple[float, float], figsize: Tuple[float, float] | None, show: bool, supports: bool, values_only: Literal[True], annotations: bool) Tuple[numpy.ndarray, numpy.ndarray][source]
show_structure(verbosity: int, scale: float, offset: Tuple[float, float], figsize: Tuple[float, float] | None, show: Literal[False], supports: bool, values_only: Literal[False], annotations: bool) matplotlib.figure.Figure
show_structure(verbosity: int = 0, scale: float = 1.0, offset: Tuple[float, float] = (0, 0), figsize: Tuple[float, float] | None = None, show: Literal[True] = True, supports: bool = True, values_only: Literal[False] = False, annotations: bool = False) None

Plot the structure.

Args:

verbosity (int, optional): 0: All information, 1: Suppress information. Defaults to 0. scale (float, optional): Scale of the plot. Defaults to 1.0. offset (Tuple[float, float], optional): Offset the plots location on the figure. Defaults to (0, 0). figsize (Optional[Tuple[float, float]], optional): Change the figure size. Defaults to None. show (bool, optional): Plot the result or return a figure. Defaults to True. supports (bool, optional): Plot the supports. Defaults to True. values_only (bool, optional): Return the values that would be plotted as tuple containing

two arrays: (x, y). Defaults to False.

annotations (bool, optional): if True, structure annotations are plotted. It includes section name.

Returns:

Figure: If show is False, return a figure.

change_plot_colors(plot_colors: Dict) None[source]

Calls the change_plot_colors method of the plotter object

Args:

colors (Dict): A dictionary containing plot components and colors as key-value pairs.

show_bending_moment(factor: float | None, verbosity: int, scale: float, offset: Tuple[float, float], figsize: Tuple[float, float] | None, show: bool, values_only: Literal[True]) Tuple[numpy.ndarray, numpy.ndarray][source]
show_bending_moment(factor: float | None, verbosity: int, scale: float, offset: Tuple[float, float], figsize: Tuple[float, float] | None, show: Literal[False], values_only: Literal[False]) matplotlib.figure.Figure
show_bending_moment(factor: float | None = None, verbosity: int = 0, scale: float = 1.0, offset: Tuple[float, float] = (0, 0), figsize: Tuple[float, float] | None = None, show: Literal[True] = True, values_only: Literal[False] = False) None

Plot the bending moment.

Args:

factor (Optional[float], optional): Influence the plotting scale. Defaults to None. verbosity (int, optional): 0: All information, 1: Suppress information. Defaults to 0. scale (float, optional): Scale of the plot. Defaults to 1. offset (Tuple[float, float], optional): Offset the plots location on the figure. Defaults to (0, 0). figsize (Optional[Tuple[float, float]], optional): Change the figure size. Defaults to None. show (bool, optional): Plot the result or return a figure. Defaults to True. values_only (bool, optional): Return the values that would be plotted as tuple containing

two arrays: (x, y). Defaults to False.

Returns:

Figure: If show is False, return a figure.

show_axial_force(factor: float | None, verbosity: int, scale: float, offset: Tuple[float, float], figsize: Tuple[float, float] | None, show: bool, values_only: Literal[True]) Tuple[numpy.ndarray, numpy.ndarray][source]
show_axial_force(factor: float | None, verbosity: int, scale: float, offset: Tuple[float, float], figsize: Tuple[float, float] | None, show: Literal[False], values_only: Literal[False]) matplotlib.figure.Figure
show_axial_force(factor: float | None = None, verbosity: int = 0, scale: float = 1.0, offset: Tuple[float, float] = (0, 0), figsize: Tuple[float, float] | None = None, show: Literal[True] = True, values_only: Literal[False] = False) None

Plot the axial force.

Args:

factor (Optional[float], optional): Influence the plotting scale. Defaults to None. verbosity (int, optional): 0: All information, 1: Suppress information. Defaults to 0. scale (float, optional): Scale of the plot. Defaults to 1. offset (Tuple[float, float], optional): Offset the plots location on the figure. Defaults to (0, 0). figsize (Optional[Tuple[float, float]], optional): Change the figure size. Defaults to None. show (bool, optional): Plot the result or return a figure. Defaults to True. values_only (bool, optional): Return the values that would be plotted as tuple containing

two arrays: (x, y). Defaults to False.

Returns:

Figure: If show is False, return a figure.

show_shear_force(factor: float | None, verbosity: int, scale: float, offset: Tuple[float, float], figsize: Tuple[float, float] | None, show: bool, values_only: Literal[True]) Tuple[numpy.ndarray, numpy.ndarray][source]
show_shear_force(factor: float | None, verbosity: int, scale: float, offset: Tuple[float, float], figsize: Tuple[float, float] | None, show: Literal[False], values_only: Literal[False]) matplotlib.figure.Figure
show_shear_force(factor: float | None = None, verbosity: int = 0, scale: float = 1.0, offset: Tuple[float, float] = (0, 0), figsize: Tuple[float, float] | None = None, show: Literal[True] = True, values_only: Literal[False] = False) None

Plot the shear force.

Args:

factor (Optional[float], optional): Influence the plotting scale. Defaults to None. verbosity (int, optional): 0: All information, 1: Suppress information. Defaults to 0. scale (float, optional): Scale of the plot. Defaults to 1. offset (Tuple[float, float], optional): Offset the plots location on the figure. Defaults to (0, 0). figsize (Optional[Tuple[float, float]], optional): Change the figure size. Defaults to None. show (bool, optional): Plot the result or return a figure. Defaults to True. values_only (bool, optional): Return the values that would be plotted as tuple containing

two arrays: (x, y). Defaults to False.

Returns:

Figure: If show is False, return a figure.

show_reaction_force(verbosity: int, scale: float, offset: Tuple[float, float], figsize: Tuple[float, float] | None, show: Literal[False]) matplotlib.figure.Figure[source]
show_reaction_force(verbosity: int = 0, scale: float = 1.0, offset: Tuple[float, float] = (0, 0), figsize: Tuple[float, float] | None = None, show: Literal[True] = True) None

Plot the reaction force.

Args:

verbosity (int, optional): 0: All information, 1: Suppress information. Defaults to 0. scale (float, optional): Scale of the plot. Defaults to 1. offset (Tuple[float, float], optional): Offset the plots location on the figure. Defaults to (0, 0). figsize (Optional[Tuple[float, float]], optional): Change the figure size. Defaults to None. show (bool, optional): Plot the result or return a figure. Defaults to True.

Returns:

Figure: If show is False, return a figure.

show_displacement(factor: float | None, verbosity: int, scale: float, offset: Tuple[float, float], figsize: Tuple[float, float] | None, show: bool, linear: bool, values_only: Literal[True]) Tuple[numpy.ndarray, numpy.ndarray][source]
show_displacement(factor: float | None, verbosity: int, scale: float, offset: Tuple[float, float], figsize: Tuple[float, float] | None, show: Literal[False], linear: bool, values_only: Literal[False]) matplotlib.figure.Figure
show_displacement(factor: float | None = None, verbosity: int = 0, scale: float = 1.0, offset: Tuple[float, float] = (0, 0), figsize: Tuple[float, float] | None = None, show: Literal[True] = True, linear: bool = False, values_only: Literal[False] = False) None

Plot the displacement.

Args:

factor (Optional[float], optional): Influence the plotting scale. Defaults to None. verbosity (int, optional): 0: All information, 1: Suppress information. Defaults to 0. scale (float, optional): Scale of the plot. Defaults to 1. offset (Tuple[float, float], optional): Offset the plots location on the figure. Defaults to (0, 0). figsize (Optional[Tuple[float, float]], optional): Change the figure size. Defaults to None. show (bool, optional): Plot the result or return a figure. Defaults to True. linear (bool, optional): Don’t evaluate the displacement values in between the elements. Defaults to False. values_only (bool, optional): Return the values that would be plotted as tuple containing

two arrays: (x, y). Defaults to False.

Returns:

Figure: If show is False, return a figure.

show_results(verbosity: int, scale: float, offset: Tuple[float, float], figsize: Tuple[float, float] | None, show: Literal[False]) matplotlib.figure.Figure[source]
show_results(verbosity: int = 0, scale: float = 1.0, offset: Tuple[float, float] = (0, 0), figsize: Tuple[float, float] | None = None, show: Literal[True] = True) None

Plot all the results in one window.

Args:

verbosity (int, optional): 0: All information, 1: Suppress information. Defaults to 0. scale (float, optional): Scale of the plot. Defaults to 1. offset (Tuple[float, float], optional): Offset the plots location on the figure. Defaults to (0, 0). figsize (Optional[Tuple[float, float]], optional): Change the figure size. Defaults to None. show (bool, optional): Plot the result or return a figure. Defaults to True.

Returns:

Figure: If show is False, return a figure.

get_node_results_system(node_id: None = None) List[Dict[str, int | float]][source]
get_node_results_system(node_id: int) Dict[str, int | float]

Get the node results. These are the opposite of the forces and displacements working on the elements and may seem counter intuitive.

Args:
node_id (int, optional): The node’s ID. If node_id == None or 0, the results of all nodes are returned.

Defaults to None.

Returns:
Union[ List[Dict[str, Union[int, float]]], Dict[str, Union[int, float]] ]:

If node_id == 0, returns a list containing tuples with the results: [(id, Fx, Fy, Tz, ux, uy, phi_z), (id, Fx, Fy…), () .. ] If node_id > 0, returns a dict with the results: {“id”: id, “Fx”: Fx, “Fy”: Fy, “Tz”: Tz, “ux”: ux, “uy”: uy, “phi_z”: phi_z}

get_node_displacements(node_id: None) List[Dict[str, Any]][source]
get_node_displacements(node_id: int) Dict[str, Any]

Get the node displacements.

Args:
node_id (int, optional): The node’s ID. If node_id == None or 0, the results of all nodes are returned.

Defaults to None.

Returns:
Union[List[Dict[str, Any]], Dict[str, Any]]: If node_id == 0, returns a list containing

tuples with the results: [(id, ux, uy, phi_z), (id, ux, uy, phi_z), … (id, ux, uy, phi_z) ] If node_id > 0, returns a dict with the results: {“id”: id, “ux”: ux, “uy”: uy, “phi_z”: phi_z}

get_element_results(element_id: None, verbose: bool) List[Dict[str, Any]][source]
get_element_results(element_id: int, verbose: bool) Dict[str, Any]

Get the element results.

Args:
element_id (int, optional): The element’s ID. If element_id == None or 0, the results of all elements

are returned. Defaults to None.

verbose (bool, optional): If set to True, then numerical results for the deflection and the bending

moment are also returned. Defaults to False.

Returns:
Union[List[Dict[str, Any]], Dict[str, Any]]: If element_id == 0,
returns a list containing dicts with the results: [{“id”: id, “length”: length, “alpha”: alpha,

“umax”: umax, “umin”: umin, “u”: u, “wmax”: wmax, “wmin”: wmin, “w”: w, “Mmin”: Mmin, “Mmax”: Mmax, “M”: M, “Qmin”: Qmin, “Qmax”: Qmax, “Q”: Q, “Nmin”: Nmin, “Nmax”: Nmax, “N”: N, “q”: q}, … ]

If element_id > 0, returns a dict with the results: {“id”: id, “length”: length, “alpha”: alpha,

“umax”: umax, “umin”: umin, “u”: u, “wmax”: wmax, “wmin”: wmin, “w”: w, “Mmin”: Mmin, “Mmax”: Mmax, “M”: M, “Qmin”: Qmin, “Qmax”: Qmax, “Q”: Q, “Nmin”: Nmin, “Nmax”: Nmax, “N”: N, “q”: q}

get_element_result_range(unit: Literal['shear', 'moment', 'axial'], minmax: Literal['min', 'max', 'abs']) List[float][source]
get_element_result_range(unit: Literal['shear', 'moment', 'axial'], minmax: Literal['both']) List[Tuple[float, float]]

Get the element results. Returns a list with the min/max results of each element for a certain unit.

Args:

unit (str): “shear”, “moment”, or “axial” minmax (str), optional: “min”, “max”, “abs”, or “both”. Defaults to “abs”.

Note that “both” returns a tuple with two values: (min, max)

Raises:

NotImplementedError: If the unit is not implemented.

Returns:

List[Union[float, Tuple[float]]]: List with min and/or max results of each element for a certain unit.

get_node_result_range(unit: Literal['ux', 'uy', 'phi_z']) List[float][source]

Get the node results. Returns a list with the node results for a certain unit.

Args:

unit (str): “uy”, “ux”, or “phi_z”

Raises:

NotImplementedError: If the unit is not implemented.

Returns:

List[float]: List with the node results for a certain unit.

find_node_id(vertex: anastruct.vertex.Vertex | Sequence[float], tolerance: float = 1e-09) int | None[source]

Find the ID of a certain location.

Args:

vertex (Union[Vertex, Sequence[float]]): Vertex_xz, [x, y], (x, y) tolerance (float): Tolerance for matching existing node locations (length units). Defaults to 1e-9.

Raises:

TypeError: vertex must be a list, tuple or Vertex

Returns:

Optional[int]: id of the node at the location of the vertex

nodes_range(dimension: anastruct._types.Dimension) List[float | Tuple[float, float] | None][source]

Retrieve a list with coordinates x or y.

Args:

dimension (str): “both”, ‘x’ or ‘y’

Returns:

List[Union[float, Tuple[float, float], None]]: List with coordinates x or y

nearest_node(dimension: anastruct._types.Dimension, val: float | Sequence[float]) int | None[source]

Retrieve the nearest node ID.

Args:

dimension (str): “both”, ‘x’, ‘y’ or ‘z’ val (Union[float, Sequence[float]]): Value of the dimension.

Returns:

Union[int, None]: ID of the node.

discretize(n: int = 10) None[source]

Discretize the elements. Takes an already defined SystemElements object and increases the number of elements.

Args:

n (int, optional): Divide the elements into n sub-elements.. Defaults to 10.

remove_loads(dead_load: bool = False) None[source]

Remove all the applied loads from the structure.

Args:

dead_load (bool, optional): Also remove the self-weights? Defaults to False.

apply_load_case(loadcase: anastruct.fem.util.load.LoadCase) None[source]

Apply a load case to the structure.

Args:

loadcase (LoadCase): Load case to apply.

get_stiffness_matrix(element_id: int) numpy.ndarray | None[source]

Return the stiffness matrix for a specific element by its ID. Args:

element_id (int): ID of the element.

Returns: Optional[Union[list, None]]: The stiffness matrix of the element if it exists, otherwise None.

__deepcopy__(_: str) SystemElements[source]

Deepcopy the SystemElements object.

Args:

_ (str): Unnecessary argument.

Returns:

SystemElements: Copied SystemElements object.

anastruct.fem.system._negative_index_to_id(idx: int, collection: Collection[int]) int[source]

Convert a negative index to a positive index. (That is, allowing the Pythonic negative indexing)

Args:

idx (int): Index to convert collection (Collection[int]): Collection of indices to check against

Raises:

TypeError: If the index is not an integer

Returns:

int: Positive index