logarithmic_spiral_evaluate

compas.geometry.logarithmic_spiral_evaluate(t, a, b, z=0)[source]

Evalutes a logarithmic spiral at a parameter.

The analytical polar equation is r = a * exp(b * theta).

Parameters

  • t (float) – Parameter.

  • a (float) – The angle of the tangent at the beginning is equal to a.

  • b (float) – The radius between turns is equal to 2 * pi * b.

  • z (float, optional) – Elevation of the spiral segment above the XY plane.

Returns

[float, float, float] – The XYZ coordinates.

References