concreteproperties.pre.CPGeom

class CPGeom(geom, material)

Bases: object

Watered down implementation of the sectionproperties Geometry object, optimised for concreteproperties.

Inits the CPGeom class.

Parameters

• geom (Polygon) – Shapely polygon defining the geometry

• material (Material) – Material to apply to the geometry

Methods

calculate_area	Calculates the area of the geometry.
calculate_centroid	Calculates the centroid of the geometry.
calculate_extents	Calculates the minimum and maximum x and y values among the points describing the geometry.
create_facets	Generates a list of facets given a list of points and a facet offset.
create_line_segment	Creates a shapely line string defined by a point and vector and bounded by bounds.
create_points_and_facets	Creates a list of points and facets from a shapely polygon.
plot_geometry	Plots the geometry.
round_geometry	Rounds the coordinates in geometry to tolerance tol.
sort_polys	Sorts polygons that are above and below the line.
split_section	Splits the geometry about a line.
to_sp_geom	Converts self to a sectionproperties geometry object.

round_geometry(geometry, tol)

Rounds the coordinates in geometry to tolerance tol.

Parameters

• geometry (Polygon) – Geometry to round

• tol (int) – Number of decimal places to round

Returns

Polygon – Rounded geometry

create_points_and_facets(geometry)

Creates a list of points and facets from a shapely polygon.

Parameters

geometry (Polygon) – Shapely polygon from which to create points and facets

Returns

Tuple[List[Tuple[float, float]], List[Tuple[int, int]]] – Points and facets

create_facets(points_list, offset=0)

Generates a list of facets given a list of points and a facet offset.

Parameters

• points_list (List[Tuple[float, float]]) – List of ordered points to create facets from

• offset (int, default: 0) – Facet offset integer

Returns

List[Tuple[int, int]] – List of facets

calculate_area()

Calculates the area of the geometry.

Returns

float – Geometry area

calculate_centroid()

Calculates the centroid of the geometry.

Returns

Tuple[float, float] – Geometry centroid

calculate_extents()

Calculates the minimum and maximum x and y values among the points describing the geometry.

Returns

Tuple[float, float, float, float] – Extents (x_min, x_max, y_min, y_max)

split_section(point, theta)

Splits the geometry about a line.

Parameters

• point (Tuple[float, float]) – Point on line

• theta (float) – Angle line makes with horizontal axis

Returns

Tuple[List[CPGeom], List[CPGeom]] – Geometries above and below the line

create_line_segment(point, vector, bounds)

Creates a shapely line string defined by a point and vector and bounded by bounds.

Parameters

• point (Tuple[float, float]) – Point on line

• vector (Tuple[float, float]) – Vector defining direction of line

• bounds (Tuple[float, float, float, float]) – Bounds of the geometry

Returns

LineString – Shapely line string

sort_polys(polys, point, vector)

Sorts polygons that are above and below the line.

Parameters

• polys (List[Polygon]) – Polygons to sort

• point (Tuple[float, float]) – Point on line

• vector (Tuple[float, float]) – Vector defining direction of line

Returns

Tuple[List[Polygon], List[Polygon]] – Polygons above and below the line

plot_geometry(title='Cross-Section Geometry', **kwargs)

Plots the geometry.

Parameters

• title (str, default: 'Cross-Section Geometry') – Plot title

• kwargs – Passed to plot_geometry()

Returns

Axes – Matplotlib axes object

to_sp_geom()

Converts self to a sectionproperties geometry object.

Returns

Geometry – sectionproperties geometry object