"""
Customizing Matplotlib with style sheets and rcParams
=====================================================

Tips for customizing the properties and default styles of Matplotlib.

Using style sheets
------------------

The ``style`` package adds support for easy-to-switch plotting "styles" with
the same parameters as a
:ref:`matplotlib rc <customizing-with-matplotlibrc-files>` file (which is read
at startup to configure matplotlib).

There are a number of pre-defined styles `provided by Matplotlib`_. For
example, there's a pre-defined style called "ggplot", which emulates the
aesthetics of ggplot_ (a popular plotting package for R_). To use this style,
just add:
"""

import numpy as np
import matplotlib.pyplot as plt
import matplotlib as mpl
from cycler import cycler
plt.style.use('ggplot')
data = np.random.randn(50)

###############################################################################
# To list all available styles, use:

print(plt.style.available)

###############################################################################
# Defining your own style
# -----------------------
#
# You can create custom styles and use them by calling ``style.use`` with the
# path or URL to the style sheet. Additionally, if you add your
# ``<style-name>.mplstyle`` file to ``mpl_configdir/stylelib``, you can reuse
# your custom style sheet with a call to ``style.use(<style-name>)``. By default
# ``mpl_configdir`` should be ``~/.config/matplotlib``, but you can check where
# yours is with ``matplotlib.get_configdir()``; you may need to create this
# directory. You also can change the directory where matplotlib looks for
# the stylelib/ folder by setting the MPLCONFIGDIR environment variable,
# see :ref:`locating-matplotlib-config-dir`.
#
# Note that a custom style sheet in ``mpl_configdir/stylelib`` will
# override a style sheet defined by matplotlib if the styles have the same name.
#
# For example, you might want to create
# ``mpl_configdir/stylelib/presentation.mplstyle`` with the following::
#
#    axes.titlesize : 24
#    axes.labelsize : 20
#    lines.linewidth : 3
#    lines.markersize : 10
#    xtick.labelsize : 16
#    ytick.labelsize : 16
#
# Then, when you want to adapt a plot designed for a paper to one that looks
# good in a presentation, you can just add::
#
#    >>> import matplotlib.pyplot as plt
#    >>> plt.style.use('presentation')
#
#
# Composing styles
# ----------------
#
# Style sheets are designed to be composed together. So you can have a style
# sheet that customizes colors and a separate style sheet that alters element
# sizes for presentations. These styles can easily be combined by passing
# a list of styles::
#
#    >>> import matplotlib.pyplot as plt
#    >>> plt.style.use(['dark_background', 'presentation'])
#
# Note that styles further to the right will overwrite values that are already
# defined by styles on the left.
#
#
# Temporary styling
# -----------------
#
# If you only want to use a style for a specific block of code but don't want
# to change the global styling, the style package provides a context manager
# for limiting your changes to a specific scope. To isolate your styling
# changes, you can write something like the following:

with plt.style.context('dark_background'):
    plt.plot(np.sin(np.linspace(0, 2 * np.pi)), 'r-o')
plt.show()

###############################################################################
# .. _matplotlib-rcparams:
#
# matplotlib rcParams
# ===================
#
# .. _customizing-with-dynamic-rc-settings:
#
# Dynamic rc settings
# -------------------
#
# You can also dynamically change the default rc settings in a python script or
# interactively from the python shell. All of the rc settings are stored in a
# dictionary-like variable called :data:`matplotlib.rcParams`, which is global to
# the matplotlib package. rcParams can be modified directly, for example:

mpl.rcParams['lines.linewidth'] = 2
mpl.rcParams['lines.linestyle'] = '--'
plt.plot(data)

###############################################################################
# Note, that in order to change the usual `plot` color you have to change the
# *prop_cycle* property of *axes*:

mpl.rcParams['axes.prop_cycle'] = cycler(color=['r', 'g', 'b', 'y'])
plt.plot(data)  # first color is red

###############################################################################
# Matplotlib also provides a couple of convenience functions for modifying rc
# settings. The :func:`matplotlib.rc` command can be used to modify multiple
# settings in a single group at once, using keyword arguments:

mpl.rc('lines', linewidth=4, linestyle='-.')
plt.plot(data)

###############################################################################
# The :func:`matplotlib.rcdefaults` command will restore the standard matplotlib
# default settings.
#
# There is some degree of validation when setting the values of rcParams, see
# :mod:`matplotlib.rcsetup` for details.
#
# .. _customizing-with-matplotlibrc-files:
#
# The :file:`matplotlibrc` file
# -----------------------------
#
# Matplotlib uses :file:`matplotlibrc` configuration files to customize all
# kinds of properties, which we call 'rc settings' or 'rc parameters'. You can
# control the defaults of almost every property in Matplotlib: figure size and
# DPI, line width, color and style, axes, axis and grid properties, text and
# font properties and so on. Matplotlib looks for :file:`matplotlibrc` in four
# locations, in the following order:
#
# 1. :file:`matplotlibrc` in the current working directory, usually used for
#    specific customizations that you do not want to apply elsewhere.
#
# 2. :file:`$MATPLOTLIBRC` if it is a file, else :file:`$MATPLOTLIBRC/matplotlibrc`.
#
# 3. It next looks in a user-specific place, depending on your platform:
#
#    - On Linux and FreeBSD, it looks in
#      :file:`.config/matplotlib/matplotlibrc` (or
#      :file:`$XDG_CONFIG_HOME/matplotlib/matplotlibrc`) if you've customized
#      your environment.
#
#    - On other platforms, it looks in :file:`.matplotlib/matplotlibrc`.
#
#    See :ref:`locating-matplotlib-config-dir`.
#
# 4. :file:`{INSTALL}/matplotlib/mpl-data/matplotlibrc`, where
#    :file:`{INSTALL}` is something like
#    :file:`/usr/lib/python3.7/site-packages` on Linux, and maybe
#    :file:`C:\\Python37\\Lib\\site-packages` on Windows. Every time you
#    install matplotlib, this file will be overwritten, so if you want
#    your customizations to be saved, please move this file to your
#    user-specific matplotlib directory.
#
# Once a :file:`matplotlibrc` file has been found, it will *not* search any of
# the other paths.
#
# To display where the currently active :file:`matplotlibrc` file was
# loaded from, one can do the following::
#
#   >>> import matplotlib
#   >>> matplotlib.matplotlib_fname()
#   '/home/foo/.config/matplotlib/matplotlibrc'
#
# See below for a sample :ref:`matplotlibrc file<matplotlibrc-sample>`.
#
# .. _matplotlibrc-sample:
#
# A sample matplotlibrc file
# ~~~~~~~~~~~~~~~~~~~~~~~~~~
#
# .. literalinclude:: ../../../matplotlibrc.template
#
#
# .. _ggplot: https://ggplot2.tidyverse.org/
# .. _R: https://www.r-project.org/
# .. _provided by Matplotlib: https://github.com/matplotlib/matplotlib/tree/master/lib/matplotlib/mpl-data/stylelib
