sknano.core.geometric_regions.Cylinder

class sknano.core.geometric_regions.Cylinder(p1=None, p2=None, r=1)

Geometric3DRegion for a cylinder.

New in version 0.3.10.

Represents a cylinder of radius \(r\) around the line from \((x_1, y_1, z_1)\) to \((x_2, y_2, z_2)\).

Parameters:

p1, p2 : array_like, optional

3-tuples or Point class instances specifying the Cylinder axis from point \(p_1=(x_1,y_1,z_1)\) to \(p_2=(x_2,y_2,z_2)\).

r : float, optional

Cylinder radius \(r\)

Notes

Cylinder represents a cylinder region \(\left\{p_1+\rho\cos(\theta)\mathbf{v}_1 + \rho\sin(\theta)\mathbf{v}_2 + \mathbf{v}_3 z| 0\le\theta\le 2\pi\land 0\le\rho\le 1\land 0\le z\le 1\right\}\) where \(\mathbf{v}_3=p_2 - p_1\) and the vectors \(\{\mathbf{v}_1,\mathbf{v}_2,\mathbf{v}_3\}\) are orthogonal with \(|\mathbf{v}_1|=|\mathbf{v}_2|=1\), and \(p_1=(x_1, y_1, z_1)\) and \(p_2=(x_2,y_2,z_2)\).

Calling Cylinder with no parameters is equivalent to Cylinder(p1=[0, 0, -1], p2=[0, 0, 1], r=1).

Attributes

axis	Cylinder axis Vector \(\boldsymbol{\ell}=p_2 - p_1\).
center	Alias for centroid.
centroid	Cylinder centroid, \((c_x, c_y, c_z)\).
fmtstr	Format string.
measure	Alias for volume, which is the measure of a 3D geometric region.
p1	Cylinder axis point \(p_1=(x_1, y_1, z_1)\).
p2	Cylinder axis point \(p_2=(x_2, y_2, z_2)\).
r	Cylinder radius \(r\).
volume	Cylinder volume, \(V=\pi r^2 \ell\).

Methods

center_centroid()	Center centroid on origin.
contains(point)	Test region membership of point in Cylinder.
rotate([angle, axis, anchor_point, ...])	Rotate GeometricRegion points and vectors.
todict()	Returns a dict of the Cylinder constructor parameters.
translate(t[, fix_anchor_points])	Translate GeometricRegion points and vectors by Vector t.