matplotlib.colors.Colormap

class matplotlib.colors.Colormap(name, N=256)[source]

Bases: object

Baseclass for all scalar to RGBA mappings.

Typically, Colormap instances are used to convert data values (floats) from the interval [0, 1] to the RGBA color that the respective Colormap represents. For scaling of data into the [0, 1] interval see matplotlib.colors.Normalize. Subclasses of matplotlib.cm.ScalarMappable make heavy use of this data -> normalize -> map-to-color processing chain.

Parameters
namestr

The name of the colormap.

Nint

The number of rgb quantization levels.

__call__(X, alpha=None, bytes=False)[source]
Parameters
Xfloat or int, ndarray or scalar

The data value(s) to convert to RGBA. For floats, X should be in the interval [0.0, 1.0] to return the RGBA values X*100 percent along the Colormap line. For integers, X should be in the interval [0, Colormap.N) to return RGBA values indexed from the Colormap with index X.

alphafloat or array-like or None

Alpha must be a scalar between 0 and 1, a sequence of such floats with shape matching X, or None.

bytesbool

If False (default), the returned RGBA values will be floats in the interval [0, 1] otherwise they will be uint8s in the interval [0, 255].

Returns
Tuple of RGBA values if X is scalar, otherwise an array of
RGBA values with a shape of X.shape + (4, ).
colorbar_extend

When this colormap exists on a scalar mappable and colorbar_extend is not False, colorbar creation will pick up colorbar_extend as the default value for the extend keyword in the matplotlib.colorbar.Colorbar constructor.

copy()[source]

Return a copy of the colormap.

get_bad()[source]

Get the color for masked values.

get_over()[source]

Get the color for high out-of-range values.

get_under()[source]

Get the color for low out-of-range values.

is_gray()[source]

Return whether the colormap is grayscale.

reversed(name=None)[source]

Return a reversed instance of the Colormap.

Note

This function is not implemented for base class.

Parameters
namestr, optional

The name for the reversed colormap. If it's None the name will be the name of the parent colormap + "_r".

set_bad(color='k', alpha=None)[source]

Set the color for masked values.

set_extremes(*, bad=None, under=None, over=None)[source]

Set the colors for masked (bad) values and, when norm.clip = False, low (under) and high (over) out-of-range values.

set_over(color='k', alpha=None)[source]

Set the color for high out-of-range values.

set_under(color='k', alpha=None)[source]

Set the color for low out-of-range values.

with_extremes(*, bad=None, under=None, over=None)[source]

Return a copy of the colormap, for which the colors for masked (bad) values and, when norm.clip = False, low (under) and high (over) out-of-range values, have been set accordingly.

Examples using matplotlib.colors.Colormap