colors

For a visual representation of the matplotlib colormaps, see the “Color” section in the gallery.

matplotlib.colors

A module for converting numbers or color arguments to RGB or RGBA

RGB and RGBA are sequences of, respectively, 3 or 4 floats in the range 0-1.

This module includes functions and classes for color specification conversions, and for mapping numbers to colors in a 1-D array of colors called a colormap. Colormapping typically involves two steps: a data array is first mapped onto the range 0-1 using an instance of Normalize or of a subclass; then this number in the 0-1 range is mapped to a color using an instance of a subclass of Colormap. Two are provided here: LinearSegmentedColormap, which is used to generate all the built-in colormap instances, but is also useful for making custom colormaps, and ListedColormap, which is used for generating a custom colormap from a list of color specifications.

The module also provides functions for checking whether an object can be interpreted as a color (is_color_like()), for converting such an object to an RGBA tuple (to_rgba()) or to an HTML-like hex string in the #rrggbb format (to_hex()), and a sequence of colors to an (n, 4) RGBA array (to_rgba_array()). Caching is used for efficiency.

Commands which take color arguments can use several formats to specify the colors. For the basic built-in colors, you can use a single letter

• b: blue
• g: green
• r: red
• c: cyan
• m: magenta
• y: yellow
• k: black
• w: white

To use the colors that are part of the active color cycle in the current style, use C followed by a digit. For example:

• C0: The first color in the cycle
• C1: The second color in the cycle

Gray shades can be given as a string encoding a float in the 0-1 range, e.g.:

color = '0.75'

For a greater range of colors, you have two options. You can specify the color using an html hex string, as in:

color = '#eeefff'

(possibly specifying an alpha value as well), or you can pass an (r, g, b) or (r, g, b, a) tuple, where each of r, g, b and a are in the range [0,1].

Finally, legal html names for colors, like ‘red’, ‘burlywood’ and ‘chartreuse’ are supported.

Classes

BoundaryNorm(boundaries, ncolors[, clip])	Generate a colormap index based on discrete intervals.
Colormap(name[, N])	Baseclass for all scalar to RGBA mappings.
LightSource([azdeg, altdeg, hsv_min_val, …])	Create a light source coming from the specified azimuth and elevation.
LinearSegmentedColormap(name, segmentdata[, …])	Colormap objects based on lookup tables using linear segments.
ListedColormap(colors[, name, N])	Colormap object generated from a list of colors.
LogNorm([vmin, vmax, clip])	Normalize a given value to the 0-1 range on a log scale
NoNorm([vmin, vmax, clip])	Dummy replacement for Normalize, for the case where we want to use indices directly in a ScalarMappable .
Normalize([vmin, vmax, clip])	A class which, when called, can normalize data into the [0.0, 1.0] interval.
PowerNorm(gamma[, vmin, vmax, clip])	Normalize a given value to the [0, 1] interval with a power-law scaling.
SymLogNorm(linthresh[, linscale, vmin, …])	The symmetrical logarithmic scale is logarithmic in both the positive and negative directions from the origin.

Functions

from_levels_and_colors(levels, colors[, extend])	A helper routine to generate a cmap and a norm instance which behave similar to contourf’s levels and colors arguments.
hsv_to_rgb(hsv)	convert hsv values in a numpy array to rgb values
rgb_to_hsv(arr)	convert float rgb values (in the range [0, 1]), in a numpy array to hsv
to_hex(c[, keep_alpha])	Convert c to a hex color.
to_rgb(c)	Convert c to an RGB color, silently dropping the alpha channel.
to_rgba(c[, alpha])	Convert c to an RGBA color.
to_rgba_array(c[, alpha])	Convert c to a (n, 4) array of RGBA colors.
is_color_like(c)	Return whether c can be interpreted as an RGB(A) color.
makeMappingArray(N, data[, gamma])	Create an N -element 1-d lookup table
get_named_colors_mapping()	Return the global mapping of names to named colors.