#!/usr/bin/env python
# -*- coding: utf-8 -*-
# ******************************************************
#   Mosel Python Example Problems
#   =============================
#
#   file invert_matrix.py
#   `````````````````````
#   Invert a Mosel matrix in Python using NumPy.
#
#   (c) 2018 Fair Isaac Corporation
#       author: J.Müller
# *******************************************************
import platform
import numpy as np
from numpy.linalg import inv


def invert_matrix(dictionary, indices1, indices2):
    """ Compute inverse matrix of a two dimensional Mosel array.

    Parameters
    ----------
    dictionary : dict
        Two dimensional Python dictionary (Mosel array).
    indices1 : range
        Range of all indices in dimension one.
    indices2 : iterable
        Range of all indices in dimension two.

    Returns
    -------
    dict
        Inverse matrix as two dimensional Python dictionary (Mosel array).
    """
    # Convert dictionary to NumPy array.
    np_a = np.array([[dictionary[i, j] for j in indices2] for i in indices1])

    # Compute inverse matrix.
    np_a_inverse = inv(np_a)
    print(np_a_inverse)

    # Convert NumPy array to dictionary.
    a_inverse = {(i, j): np_a_inverse[i, j] for j in indices2 for i in indices1}
    return a_inverse


if __name__ == "__main__":
    print("Python library version:", platform.python_version())
    print("NumPy library version: ", np.__version__)