statsmodels.robust.norms.AndrewWave.rho¶
- AndrewWave.rho(z)[source]¶
The robust criterion function for Andrew’s wave.
\[\begin{split}\rho(z) = \begin{cases} a^2 (1 - \cos(z/a)) & \text{for } |z| \le a\pi \\ 2a^2 & \text{for } |z| > a\pi \end{cases}\end{split}\]- Parameters:¶
- zarray_like
1d array
- Returns:¶
- rho
ndarray The value of the robust criterion function.
- rho