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

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 \((x_2, y_2, z_2)\).


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 \(r\)


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).


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, \(V=\pi r^2 \ell\).


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.