cr.sparse.opt.prox_zero¶
- cr.sparse.opt.prox_zero()[source]¶
Returns a prox-capable wrapper for the function \(f(x)=0\)
- Returns
A prox-capable function
- Return type
The function \(f(x)=0\) is the indicator function for the vector space \(\RR^n\).
The proximal operator
(1)¶\[p_f(x, t) = \text{arg} \min_{z \in \RR^n} f(x) + \frac{1}{2t} \| z - x \|_2^2\]reduces to:
(2)¶\[p_f(x, t) = \text{arg} \min_{z \in \RR^n} \frac{1}{2t} \| z - x \|_2^2 = x\]
