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

.. only:: html

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

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

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

.. _sphx_glr_auto_examples_indiv_funcs_unitary_ft.py:


Unitary FT
==========
Demonstrate new argument to ft and ift that allows you to take an FT that's
unitary in the vector sense -- this way, you don't have to e.g. multiply by dt
and divide by the  number of points.
(This is a standard capability with raw numpy, but we just had not much use for
it before)

.. GENERATED FROM PYTHON SOURCE LINES 10-48



.. image-sg:: /auto_examples/indiv_funcs/images/sphx_glr_unitary_ft_001.png
   :alt: time domain, frequency domain
   :srcset: /auto_examples/indiv_funcs/images/sphx_glr_unitary_ft_001.png, /auto_examples/indiv_funcs/images/sphx_glr_unitary_ft_001_2_00x.png 2.00x
   :class: sphx-glr-single-img





.. code-block:: Python

    from pylab import *
    from pyspecdata import *

    fig, (ax_time, ax_freq) = subplots(2, 1)
    t = nddata(r_[0:0.5:1e-3], "t2")  # 1 kHz SW with a freq. resolution of 1/0.5=2 Hz
    fake_data = exp(1j * 2 * pi * 100 * t - 10 * t * pi)  # 10 Hz wide line at 100 Hz offset
    fake_data.add_noise(0.1).set_units("t2", "s")
    logger.info(strm("vector norm of fake data, before ft", linalg.norm(fake_data.data)))
    plot(
        fake_data,
        ax=ax_time,
        alpha=0.5,
        label="vector norm=%g" % linalg.norm(fake_data.data),
    )
    ax_time.set_title("time domain")
    ax_freq.set_title("frequency domain")
    fake_data.ft("t2", shift=True, unitary=True)
    logger.info(
        strm("vector norm of fake data, after unitary ft", linalg.norm(fake_data.data))
    )
    assert fake_data.get_ft_prop("t2", "dt") == 1e-3
    plot(
        fake_data,
        ax=ax_freq,
        alpha=0.5,
        label="vector norm=%g" % linalg.norm(fake_data.data),
    )
    fake_data.ift(
        "t2"
    )  # because we already used "unitary" for the ft, it knows the ift is unitary.
    #    In fact, passing "unitary" as a keyword argument will generate an error here
    logger.info(
        strm("vector norm of fake data, after unitary ift", linalg.norm(fake_data.data))
    )
    ax_time.legend(**dict(bbox_to_anchor=(1.05, 1), loc=2, borderaxespad=0.0))
    ax_freq.legend(**dict(bbox_to_anchor=(1.05, 1), loc=2, borderaxespad=0.0))
    fig.tight_layout()
    show()


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

   **Total running time of the script:** (0 minutes 0.586 seconds)


.. _sphx_glr_download_auto_examples_indiv_funcs_unitary_ft.py:

.. only:: html

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

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

      :download:`Download Jupyter notebook: unitary_ft.ipynb <unitary_ft.ipynb>`

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

      :download:`Download Python source code: unitary_ft.py <unitary_ft.py>`


.. only:: html

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

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