.. _colors: ***************** Specifying Colors ***************** In almost all places in matplotlib where a color can be specified by the user it can be provided as: * an RGB or RGBA tuple of float values in ``[0, 1]`` (e.g., ``(0.1, 0.2, 0.5)`` or ``(0.1, 0.2, 0.5, 0.3)``) * a hex RGB or RGBA string (e.g., ``'#0F0F0F'`` or ``'#0F0F0F0F'``) * a string representation of a float value in ``[0, 1]`` inclusive for gray level (e.g., ``'0.5'``) * one of ``{'b', 'g', 'r', 'c', 'm', 'y', 'k', 'w'}`` * a X11/CSS4 color name * a name from the `xkcd color survey `__ prefixed with ``'xkcd:'`` (e.g., ``'xkcd:sky blue'``) * one of ``{'C0', 'C1', 'C2', 'C3', 'C4', 'C5', 'C6', 'C7', 'C8', 'C9'}`` * one of ``{'tab:blue', 'tab:orange', 'tab:green', 'tab:red', 'tab:purple', 'tab:brown', 'tab:pink', 'tab:gray', 'tab:olive', 'tab:cyan'}`` which are the Tableau Colors from the 'T10' categorical palette (which is the default color cycle). All string specifications of color are case-insensitive. ``'CN'`` color selection ------------------------ Color can be specified by a string matching the regex ``C[0-9]``. This can be passed any place that a color is currently accepted and can be used as a 'single character color' in format-string to `matplotlib.Axes.plot`. The single digit is the index into the default property cycle (``matplotlib.rcParams['axes.prop_cycle']``). If the property cycle does not include ``'color'`` then black is returned. The color is evaluated when the artist is created. For example, .. plot:: :include-source: True 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') will use the first color for the title and then plot using the second and third colors of each style's ``mpl.rcParams['axes.prop_cycle']``. xkcd v X11/CSS4 --------------- The xkcd colors are derived from a user survey conducted by the webcomic xkcd. `Details of the survey are available on the xkcd blog `__. Out of 148 colors in the CSS color list, there are 95 name collisions between the X11/CSS4 names and the xkcd names, all but 3 of which have different hex values. For example ``'blue'`` maps to ``'#0000FF'`` where as ``'xkcd:blue'`` maps to ``'#0343DF'``. Due to these name collisions all of the xkcd colors have ``'xkcd:'`` prefixed. As noted in the blog post, while it might be interesting to re-define the X11/CSS4 names based on such a survey, we do not do so unilaterally. The name collisions are shown in the table below; the color names where the hex values agree are shown in bold. .. plot:: import matplotlib.pyplot as plt import matplotlib._color_data as mcd import matplotlib.patches as mpatch overlap = {name for name in mcd.CSS4_COLORS if "xkcd:" + name in mcd.XKCD_COLORS} fig = plt.figure(figsize=[4.8, 16]) ax = fig.add_axes([0, 0, 1, 1]) for j, n in enumerate(sorted(overlap, reverse=True)): weight = None cn = mcd.CSS4_COLORS[n] xkcd = mcd.XKCD_COLORS["xkcd:" + n].upper() if cn == xkcd: weight = 'bold' r1 = mpatch.Rectangle((0, j), 1, 1, color=cn) r2 = mpatch.Rectangle((1, j), 1, 1, color=xkcd) txt = ax.text(2, j+.5, ' ' + n, va='center', fontsize=10, weight=weight) ax.add_patch(r1) ax.add_patch(r2) ax.axhline(j, color='k') ax.text(.5, j + 1.5, 'X11', ha='center', va='center') ax.text(1.5, j + 1.5, 'xkcd', ha='center', va='center') ax.set_xlim(0, 3) ax.set_ylim(0, j + 2) ax.axis('off')