TukeyBiweight.
weights
Tukey’s biweight weighting function for the IRLS algorithm
The psi function scaled by z
z : array_like
1d array
weights : ndarray
psi(z) = (1 - (z/c)**2)**2 for |z| <= R psi(z) = 0 for |z| > R
psi(z) = (1 - (z/c)**2)**2 for |z| <= R
psi(z) = 0 for |z| > R