ScreenERI3
==========

Overview
--------
ScreenERI3 implements Schwarz-type ERI screening data and exposes the
underlying screening vectors/matrices to Python as read-only memoryviews.

Constructor
-----------

.. code-block:: python

   ScreenERI3(pp, ijij, cutoff)

Parameters
----------
* **pp** *(ndarray, naux)* - auxiliary per-shell screening vector.
* **ijij** *(ndarray, nsh x nsh)* - per-shell-pair screening estimates for primary basis.
* **cutoff** *(float)* - screening cutoff threshold.

Properties
----------
* ``pp`` - read-only memoryview to internal screening vector.
* ``ijij`` - read-only memoryview to internal screening matrix.
* ``nao`` - number of atomic orbitals in primary basis.
* ``naux`` - number of auxiliary AOs.

Notes
-----
* The screening object is consumed by :class:`libintx.Jengine.set_screening`
  for efficient ERI screening.