.. DO NOT EDIT. .. THIS FILE WAS AUTOMATICALLY GENERATED BY SPHINX-GALLERY. .. TO MAKE CHANGES, EDIT THE SOURCE PYTHON FILE: .. "tutorials/colors/colors.py" .. LINE NUMBERS ARE GIVEN BELOW. .. only:: html .. meta:: :keywords: codex .. note:: :class: sphx-glr-download-link-note Click :ref:`here ` to download the full example code .. rst-class:: sphx-glr-example-title .. _sphx_glr_tutorials_colors_colors.py: ***************** Specifying Colors ***************** Matplotlib recognizes the following formats to specify a color. +--------------------------------------+--------------------------------------+ | Format | Example | +======================================+======================================+ | RGB or RGBA (red, green, blue, alpha)| - ``(0.1, 0.2, 0.5)`` | | tuple of float values in a closed | - ``(0.1, 0.2, 0.5, 0.3)`` | | interval [0, 1]. | | +--------------------------------------+--------------------------------------+ | Case-insensitive hex RGB or RGBA | - ``'#0f0f0f'`` | | string. | - ``'#0f0f0f80'`` | +--------------------------------------+--------------------------------------+ | Case-insensitive RGB or RGBA string | - ``'#abc'`` as ``'#aabbcc'`` | | equivalent hex shorthand of | - ``'#fb1'`` as ``'#ffbb11'`` | | duplicated characters. | | +--------------------------------------+--------------------------------------+ | String representation of float value | - ``'0'`` as black | | in closed interval ``[0, 1]`` for | - ``'1'`` as white | | grayscale values. | - ``'0.8'`` as light gray | +--------------------------------------+--------------------------------------+ | Single character shorthand notation | - ``'b'`` as blue | | for some basic colors. | - ``'g'`` as green | | | - ``'r'`` as red | | .. note:: | - ``'c'`` as cyan | | The colors green, cyan, magenta, | - ``'m'`` as magenta | | and yellow do not coincide with | - ``'y'`` as yellow | | X11/CSS4 colors. Their particular | - ``'k'`` as black | | shades were chosen for better | - ``'w'`` as white | | visibility of colored lines | | | against typical backgrounds. | | +--------------------------------------+--------------------------------------+ | Case-insensitive X11/CSS4 color name | - ``'aquamarine'`` | | with no spaces. | - ``'mediumseagreen'`` | +--------------------------------------+--------------------------------------+ | Case-insensitive color name from | - ``'xkcd:sky blue'`` | | `xkcd color survey`_ with ``'xkcd:'``| - ``'xkcd:eggshell'`` | | prefix. | | +--------------------------------------+--------------------------------------+ | Case-insensitive Tableau Colors from | - ``'tab:blue'`` | | 'T10' categorical palette. | - ``'tab:orange'`` | | | - ``'tab:green'`` | | | - ``'tab:red'`` | | | - ``'tab:purple'`` | | .. note:: This is the default color | - ``'tab:brown'`` | | cycle. | - ``'tab:pink'`` | | | - ``'tab:gray'`` | | | - ``'tab:olive'`` | | | - ``'tab:cyan'`` | +--------------------------------------+--------------------------------------+ | "CN" color spec where ``'C'`` | - ``'C0'`` | | precedes a number acting as an index | - ``'C1'`` | | into the default property cycle. +--------------------------------------+ | | :rc:`axes.prop_cycle` | | .. note:: Matplotlib indexes color | | | at draw time and defaults | | | to black if cycle does not | | | include color. | | +--------------------------------------+--------------------------------------+ .. _xkcd color survey: https://xkcd.com/color/rgb/ .. seealso:: The following links provide more information on colors in Matplotlib. * :doc:`/gallery/color/color_demo` Example * `matplotlib.colors` API * :doc:`/gallery/color/named_colors` Example "Red", "Green", and "Blue" are the intensities of those colors. In combination, they represent the colorspace. Matplotlib draws Artists based on the ``zorder`` parameter. If there are no specified values, Matplotlib defaults to the order of the Artists added to the Axes. The alpha for an Artist controls opacity. It indicates how the RGB color of the new Artist combines with RGB colors already on the Axes. The two Artists combine with alpha compositing. Matplotlib uses the equation below to compute the result of blending a new Artist. :: RGB_{new} = RGB_{below} * (1 - \alpha) + RGB_{artist} * \alpha Alpha of 1 indicates the new Artist completely covers the previous color. Alpha of 0 for top color is not visible; however, it contributes to blending for intermediate values as the cumulative result of all previous Artists. The following table contains examples. +---------------+-------------------------------------------------------------+ | Alpha value | Visual | +===============+=============================================================+ | ``0.3`` | .. image:: ../../_static/color_zorder_A.png | +---------------+-------------------------------------------------------------+ | ``1`` | .. image:: ../../_static/color_zorder_B.png | +---------------+-------------------------------------------------------------+ .. note:: Re-ordering Artists is not commutative in Matplotlib. "CN" color selection -------------------- Matplotlib converts "CN" colors to RGBA when drawing Artists. The :doc:`/tutorials/intermediate/color_cycle` section contains additional information about controlling colors and style properties. .. GENERATED FROM PYTHON SOURCE LINES 116-139 .. code-block:: default import numpy as np import matplotlib.pyplot as plt import matplotlib as mpl th = np.linspace(0, 2*np.pi, 128) def demo(sty): mpl.style.use(sty) fig, ax = plt.subplots(figsize=(3, 3)) ax.set_title('style: {!r}'.format(sty), color='C0') ax.plot(th, np.cos(th), 'C1', label='C1') ax.plot(th, np.sin(th), 'C2', label='C2') ax.legend() demo('default') demo('seaborn-v0_8') .. rst-class:: sphx-glr-horizontal * .. image-sg:: /tutorials/colors/images/sphx_glr_colors_001.png :alt: style: 'default' :srcset: /tutorials/colors/images/sphx_glr_colors_001.png, /tutorials/colors/images/sphx_glr_colors_001_2_0x.png 2.0x :class: sphx-glr-multi-img * .. image-sg:: /tutorials/colors/images/sphx_glr_colors_002.png :alt: style: 'seaborn-v0_8' :srcset: /tutorials/colors/images/sphx_glr_colors_002.png, /tutorials/colors/images/sphx_glr_colors_002_2_0x.png 2.0x :class: sphx-glr-multi-img .. GENERATED FROM PYTHON SOURCE LINES 140-162 The first color ``'C0'`` is the title. Each plot uses the second and third colors of each style's :rc:`axes.prop_cycle`. They are ``'C1'`` and ``'C2'``, respectively. .. _xkcd-colors: Comparison between X11/CSS4 and xkcd colors ------------------------------------------- The xkcd colors come from a `user survey conducted by the webcomic xkcd `__. 95 out of the 148 X11/CSS4 color names also appear in the xkcd color survey. Almost all of them map to different color values in the X11/CSS4 and in the xkcd palette. Only 'black', 'white' and 'cyan' are identical. For example, ``'blue'`` maps to ``'#0000FF'`` whereas ``'xkcd:blue'`` maps to ``'#0343DF'``. Due to these name collisions, all xkcd colors have the ``'xkcd:'`` prefix. The visual below shows name collisions. Color names where color values agree are in bold. .. GENERATED FROM PYTHON SOURCE LINES 162-206 .. code-block:: default import matplotlib.colors as mcolors import matplotlib.patches as mpatch overlap = {name for name in mcolors.CSS4_COLORS if f'xkcd:{name}' in mcolors.XKCD_COLORS} fig = plt.figure(figsize=[9, 5]) ax = fig.add_axes([0, 0, 1, 1]) n_groups = 3 n_rows = len(overlap) // n_groups + 1 for j, color_name in enumerate(sorted(overlap)): css4 = mcolors.CSS4_COLORS[color_name] xkcd = mcolors.XKCD_COLORS[f'xkcd:{color_name}'].upper() # Pick text colour based on perceived luminance. rgba = mcolors.to_rgba_array([css4, xkcd]) luma = 0.299 * rgba[:, 0] + 0.587 * rgba[:, 1] + 0.114 * rgba[:, 2] css4_text_color = 'k' if luma[0] > 0.5 else 'w' xkcd_text_color = 'k' if luma[1] > 0.5 else 'w' col_shift = (j // n_rows) * 3 y_pos = j % n_rows text_args = dict(fontsize=10, weight='bold' if css4 == xkcd else None) ax.add_patch(mpatch.Rectangle((0 + col_shift, y_pos), 1, 1, color=css4)) ax.add_patch(mpatch.Rectangle((1 + col_shift, y_pos), 1, 1, color=xkcd)) ax.text(0.5 + col_shift, y_pos + .7, css4, color=css4_text_color, ha='center', **text_args) ax.text(1.5 + col_shift, y_pos + .7, xkcd, color=xkcd_text_color, ha='center', **text_args) ax.text(2 + col_shift, y_pos + .7, f' {color_name}', **text_args) for g in range(n_groups): ax.hlines(range(n_rows), 3*g, 3*g + 2.8, color='0.7', linewidth=1) ax.text(0.5 + 3*g, -0.3, 'X11/CSS4', ha='center') ax.text(1.5 + 3*g, -0.3, 'xkcd', ha='center') ax.set_xlim(0, 3 * n_groups) ax.set_ylim(n_rows, -1) ax.axis('off') plt.show() .. image-sg:: /tutorials/colors/images/sphx_glr_colors_003.png :alt: colors :srcset: /tutorials/colors/images/sphx_glr_colors_003.png, /tutorials/colors/images/sphx_glr_colors_003_2_0x.png 2.0x :class: sphx-glr-single-img .. rst-class:: sphx-glr-timing **Total running time of the script:** ( 0 minutes 1.413 seconds) .. _sphx_glr_download_tutorials_colors_colors.py: .. only:: html .. container:: sphx-glr-footer sphx-glr-footer-example .. container:: sphx-glr-download sphx-glr-download-python :download:`Download Python source code: colors.py ` .. container:: sphx-glr-download sphx-glr-download-jupyter :download:`Download Jupyter notebook: colors.ipynb ` .. only:: html .. rst-class:: sphx-glr-signature `Gallery generated by Sphinx-Gallery `_