Source code for naginterfaces.library.examples.lapacklin.dgesv_ex

#!/usr/bin/env python3
"``naginterface.library.lapacklin.dgesv`` Python Example."

# NAG Copyright 2017-2019.

# pylint: disable=invalid-name

import numpy as np

from naginterfaces.library import lapacklin

def main():
    """
    Example for :func:`naginterfaces.library.lapacklin.dgesv`.

    Compute the solution to a real system of linear equations, :math:`AX = B`.

    >>> main()
    naginterfaces.library.lapacklin.dgesv Python Example Results.
    Solution of a square linear system with multiple right-hand sides.
    Solution X:
    [[ 1.]
     [-1.]
     [ 3.]
     [-5.]]
    Pivots:
    [2 2 3 4]
    """

    print('naginterfaces.library.lapacklin.dgesv Python Example Results.')
    print('Solution of a square linear system with multiple right-hand sides.')

    a = np.array(
        [[1.80, 2.88, 2.05, -0.89],
         [5.25, -2.95, -0.95, -3.80],
         [1.58, -2.69, -2.90, -1.04],
         [-1.11, -0.66, -0.59, 0.80]],
    )
    b = np.array(
        [[9.52], [24.35], [0.77], [-6.22]],
    )

    _, ipiv, x = lapacklin.dgesv(a, b)

    print('Solution X:')
    print(x)
    print('Pivots:')
    print(ipiv)

if __name__ == '__main__':
    import doctest
    import sys
    sys.exit(
        doctest.testmod(
            None, verbose=True, report=False,
            optionflags=doctest.REPORT_NDIFF,
        ).failed
    )