class_docstr: Projection operator onto the half-space of vectors with
  non-negative entries
  
  Parameters
  ----------
  range : `tuple` of two `int`, default=`None`
      Range on which the prox is applied. If `None` then the prox is
      applied on the whole vector
  
  Attributes
  ----------
  dtype : `{'float64', 'float32'}`
      Type of the arrays used.
code: def _call(self, coeffs: np.ndarray, step: object, out: np.ndarray):
      self._prox.call(coeffs, step, out)
  
file_path: tick/tick/prox/prox_positive.py
imports: import numpy
  from .base import Prox
  from .build.prox import ProxPositiveDouble
  from .build.prox import ProxPositiveFloat
label_desc: Use image node_id 2 for calling the ProxPositive obj's underlying member method code with example usage: obj._call(coeffs, step, out) without return types