archimedean_spiral_evaluate

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

Evalutes a spiral at a parameter. The analytical polar equation is r = a + b * theta.

Parameters

  • t (float) – Parameter

  • a (float) – Constant

  • b (float) – Constant

  • z (float, optional) – Height. Default is 0.

Returns

list – The (x, y, z) coordinates.

Notes

The radius between turns is equal to 2 * pi * b. The angle of the tangent at the beginning is equal to a. The length of an arc of the spiral from 0 t is equal to L(t) = b / 2 * t ** 2 1.

References

1

GeoGebra. Archimedean Spiral built by parametric equations. Available at: https://www.geogebra.org/m/dZuH5hWa.