.. DO NOT EDIT.
.. THIS FILE WAS AUTOMATICALLY GENERATED BY SPHINX-GALLERY.
.. TO MAKE CHANGES, EDIT THE SOURCE PYTHON FILE:
.. "examples/02_compare.py"
.. LINE NUMBERS ARE GIVEN BELOW.

.. only:: html

    .. note::
        :class: sphx-glr-download-link-note

        :ref:`Go to the end <sphx_glr_download_examples_02_compare.py>`
        to download the full example code.

.. rst-class:: sphx-glr-example-title

.. _sphx_glr_examples_02_compare.py:


2. Example: Comparison
----------------------

Here we compare the outcome of the PTRANS-I and PTRANS-II algorithm for
a random input.

.. GENERATED FROM PYTHON SOURCE LINES 8-30




.. rst-class:: sphx-glr-script-out

 .. code-block:: none

    rel. diff X1 X2:  5.766672433029218e-14
    max X1:  354407160062376.9
    max X2:  354407160062417.75
    max |M*X1 - V|:  4.178291419520974e-07
    max |M*X2 - V|:  3.284549165982753e-07






|

.. code-block:: Python


    import numpy as np

    import pentapy as pp

    size = 1000
    # create a flattened pentadiagonal matrix
    M_flat = (np.random.random((5, size)) - 0.5) * 1e-5
    V = np.random.random(size) * 1e5
    # compare the two solvers
    X1 = pp.solve(M_flat, V, is_flat=True, solver=1)
    X2 = pp.solve(M_flat, V, is_flat=True, solver=2)

    # calculate the error
    print("rel. diff X1 X2: ", np.max(np.abs(X1 - X2)) / np.max(np.abs(X1 + X2)))
    print("max X1: ", np.max(np.abs(X1)))
    print("max X2: ", np.max(np.abs(X2)))

    M = pp.create_full(M_flat, col_wise=False)
    # calculate the error
    print("max |M*X1 - V|: ", np.max(np.abs(np.dot(M, X1) - V)))
    print("max |M*X2 - V|: ", np.max(np.abs(np.dot(M, X2) - V)))


.. rst-class:: sphx-glr-timing

   **Total running time of the script:** (0 minutes 0.002 seconds)


.. _sphx_glr_download_examples_02_compare.py:

.. only:: html

  .. container:: sphx-glr-footer sphx-glr-footer-example

    .. container:: sphx-glr-download sphx-glr-download-jupyter

      :download:`Download Jupyter notebook: 02_compare.ipynb <02_compare.ipynb>`

    .. container:: sphx-glr-download sphx-glr-download-python

      :download:`Download Python source code: 02_compare.py <02_compare.py>`

    .. container:: sphx-glr-download sphx-glr-download-zip

      :download:`Download zipped: 02_compare.zip <02_compare.zip>`


.. only:: html

 .. rst-class:: sphx-glr-signature

    `Gallery generated by Sphinx-Gallery <https://sphinx-gallery.github.io>`_