compute_basisfuncs

compas.geometry.compute_basisfuncs(degree, knotvector, i, u)[source]

Compute the nonzero basis functions for a given parameter value.

Parameters:

degreeint: Degree of the curve.
knotvectorlist: Knot vector of the curve.
iint: Knot span index.
ufloat: Parameter value.

Returns:

list[float]: Basis functions.

See also

construct_knotvector
knotvector_to_knots_and_mults
knots_and_mults_to_knotvector
find_span
compute_basisfuncsderivs

Notes

In any given knot span, $\[u_{j}, u_{j + 1}$ \) at most degree + 1 of the $N_{i, d e g r e e}$ basis functions are nonzero, namely the functions $N_{j - d e g r e e, d e g r e e}, \dots, N_{j, d e g r e e}$ .

References

The NURBS Book. Chapter 2. Page 56. The NURBS Book. Chapter 2. Page 70. Algorithm A2.2.