adelie.bcd.root_lower_bound#
- adelie.bcd.root_lower_bound(*, quad: ndarray, linear: ndarray, l1: float)[source]#
Computes a lower bound on the root of BCD root function.
The lower bound \(h_\star\) is guaranteed to be non-negative and satisfies \(\varphi(h_\star) \geq 0\) where \(\varphi\) is given by
adelie.bcd.root_function()whenever \(\|v\|_2 > \lambda\). It is undefined behavior if the condition is not satisfied.- Parameters:
- quad(p,) ndarray
- linear(p,) ndarray
- l1float
- Returns:
- lowerfloat
Lower bound on the root.