gemseo.post.dataset.andrews_curves — GEMSEO 5.3.2 documentation

# Copyright 2021 IRT Saint Exupéry, https://www.irt-saintexupery.com
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public
# License version 3 as published by the Free Software Foundation.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
# Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public License
# along with this program; if not, write to the Free Software Foundation,
# Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
# Contributors:
#    INITIAL AUTHORS - initial API and implementation and/or initial
#                           documentation
#        :author: Matthias De Lozzo
#    OTHER AUTHORS   - MACROSCOPIC CHANGES
r"""Draw Andrews curves from a :class:`.Dataset`.

The :class:`.AndrewsCurves` class implements the Andrew plot, a.k.a. Andrews curves,
which is a way to visualize :math:`n` samples of a high-dimensional vector

.. math::

   x=(x_1,x_2,\ldots,x_d)\in\mathbb{R}^d

in a 2D referential by projecting each sample

.. math::

   x^{(i)}=(x_1^{(i)},x_2^{(i)},\ldots,x_d^{(i)})

onto the vector

.. math::

   \left(\frac{1}{\sqrt{2}},\sin(t),\cos(t),\sin(2t),\cos(2t), \ldots\right)

which is composed of the :math:`d` first elements of the Fourier series:

.. math::

   f_i(t)=\left(\frac{x_1^{(i)}}{\sqrt{2}},x_2^{(i)}\sin(t),x_3^{(i)}\cos(t),
   x_4^{(i)}\sin(2t),x_5^{(i)}\cos(2t),\ldots\right)

Each curve :math:`t\mapsto f_i(t)` is plotted
over the interval :math:`[-\pi,\pi]`
and structure in the data may be visible in these :math:`n` Andrews curves.

A variable name can be passed to the :meth:`.DatasetPlot.execute` method
by means of the ``classifier`` keyword
in order to color the curves according to the value of the variable name.
This is useful when the data is labeled.
"""

from __future__ import annotations

from typing import TYPE_CHECKING

from gemseo.post.dataset.dataset_plot import DatasetPlot
from gemseo.utils.string_tools import pretty_str

if TYPE_CHECKING:
    from gemseo.datasets.dataset import Dataset



[docs]
class AndrewsCurves(DatasetPlot):
    """Andrews curves."""

    def __init__(
        self,
        dataset: Dataset,
        classifier: str,
    ) -> None:
        """
        Args:
            classifier: The name of the variable to group the data.
        """  # noqa: D205, D212, D415
        super().__init__(dataset, classifier=classifier)

    def _create_specific_data_from_dataset(self) -> tuple[tuple[str, str, int]]:
        """
        Returns:
            The column of the dataset containing the group names.
        """  # noqa: D205 D212 D415
        classifier = self._specific_settings.classifier
        if classifier not in self.dataset.variable_names:
            msg = (
                "Classifier must be one of these names: "
                f"{pretty_str(self.dataset.variable_names, use_and=True)}."
            )
            raise ValueError(msg)

        return (self._get_label(classifier)[1],)
Source code for gemseo.post.dataset.andrews_curves
