colormap

View and set current colormap

Syntax

colormap map

colormap(map)

colormap(target,map)

cmap = colormap

cmap = colormap(target)

Description

colormap map sets the colormap for the current figure to one of the predefined colormaps. If you set the colormap for the figure, then axes and charts in the figure use the same colormap. The new colormap is the same length (number of colors) as the current colormap. When you use this syntax, you cannot specify a custom length for the colormap. See the More About section for more information about colormaps.

colormap(map) sets the colormap for the current figure to the colormap specified by map.

colormap(target,map) sets the colormap for the figure, axes, or chart specified by target, instead of for the current figure.

cmap = colormap returns the colormap for the current figure as a three-column matrix of RGB triplets.

cmap = colormap(target) returns the colormap for the figure, axes, or chart specified by target.

Examples

Change Colormap for Figure

Create a surface plot and set the colormap to winter.

surf(peaks)
colormap winter

Set Colormap Back to Default

First, change the colormap for the current figure to summer.

surf(peaks)
colormap summer

Now set the colormap back to your system's default value. If you have not specified a different default value, then the default colormap is parula.

colormap default

Use Different Colormaps for Each Axes in Figure

Starting in R2019b, you can display a tiling of plots using the tiledlayout and nexttile functions. Call the tiledlayout function to create a 2-by-1 tiled chart layout. Call the nexttile function to create the axes objects ax1 and ax2. Specify a different colormap for each axes by passing the axes object to the colormap function. In the upper axes, create a surface plot using the spring colormap. In the lower axes, create a surface plot using the winter colormap.

tiledlayout(2,1)
ax1 = nexttile;
surf(peaks)
colormap(ax1,spring)

ax2 = nexttile; 
surf(peaks)
colormap(ax2,winter)

Specify Number of Colors for Colormap

Specify the number of colors used in a colormap by passing an integer as an input argument to the built-in colormap. Use five colors from the parula colormap.

mesh(peaks)
colormap(parula(5))

Create Custom Colormap

Create a custom colormap by defining a three-column matrix of values between 0.0 and 1.0. Each row defines a three-element RGB triplet. The first column specifies the red intensities. The second column specifies the green intensities. The third column specifies the blue intensities.

Use a colormap of blue values by setting the first two columns to zeros.

map = [0 0 0.3
    0 0 0.4
    0 0 0.5
    0 0 0.6
    0 0 0.8
    0 0 1.0];

surf(peaks)
colormap(map)

Return Colormap Values Used in Plot

Create a surface plot of the peaks function and specify a colormap.

mesh(peaks)
colormap(autumn(5))

Return the three-column matrix of values that define the colors used in the plot. Each row is an RGB triplet color value that specifies one color of the colormap.

cmap = colormap

cmap = 5×3

    1.0000         0         0
    1.0000    0.2500         0
    1.0000    0.5000         0
    1.0000    0.7500         0
    1.0000    1.0000         0

Return Colormap Values for Specific Axes

Return the colormap values for a specific axes by passing the axes object to the colormap function.

Create a tiling of two plots using the tiledlayout and nexttile functions, which are new functions starting in R2019b. Call the tiledlayout function to create a 2-by-1 tiled chart layout. Call the nexttile function to create the axes objects ax1 and ax2. Then display two filled contour plots with different colormaps.

tiledlayout(2,1)
ax1 = nexttile;
contourf(peaks)
colormap(ax1,hot(8))

ax2 = nexttile;
contourf(peaks)
colormap(ax2,pink)

Return the colormap values used in the upper plot by passing ax1 to the colormap function. Each row is an RGB triplet color value that specifies one color of the colormap.

cmap = colormap(ax1)

cmap = 8×3

    0.3333         0         0
    0.6667         0         0
    1.0000         0         0
    1.0000    0.3333         0
    1.0000    0.6667         0
    1.0000    1.0000         0
    1.0000    1.0000    0.5000
    1.0000    1.0000    1.0000

Change Colormap for Figure with Image

Load the spine data set that returns the image X and its associated colormap map. Display X using the image function and set the colormap to map.

load spine
image(X)
colormap(map)

Input Arguments

map — Colormap for new color scheme

colormap name | three-column matrix of RGB triplets | 'default'

Colormap for the new color scheme, specified as a colormap name, a three-column matrix of RGB triplets, or 'default'. A colormap name specifies a predefined colormap with the same number of colors as the current colormap. A three-column matrix of RGB triplets specifies a custom colormap. You can create the matrix yourself, or you can call one of the predefined colormap functions to create the matrix. For example, colormap(parula(10)) sets the colormap of the current figure to a selection of 10 colors from the parula colormap.

A value of 'default' sets the colormap to the default colormap for the target object.

Colormap Name

The following table lists the predefined colormaps.

Colormap Name	Color Scale
parula
turbo
hsv
hot
cool
spring
summer
autumn
winter
gray
bone
copper
pink
jet
lines
colorcube
prism
flag
white

Three-Column Matrix

To create a custom colormap, specify map as a three-column matrix of RGB triplets where each row defines one color. An RGB triplet is a three-element row vector whose elements specify the intensities of the red, green, and blue components of the color. The intensities can be double or single values in the range [0, 1], or they can be uint8 values in the range [0, 255]. For example, this matrix defines a colormap containing five colors.

map = [0.2 0.1 0.5
    0.1 0.5 0.8
    0.2 0.7 0.6
    0.8 0.7 0.3
    0.9 1 0];

This table lists the RGB triplet values for common colors.

Color	double or single RGB Triplet	uint8 RGB Triplet
yellow	[1 1 0]	[255 255 0]
magenta	[1 0 1]	[255 0 255]
cyan	[0 1 1]	[0 255 255]
red	[1 0 0]	[255 0 0]
green	[0 1 0]	[0 255 0]
blue	[0 0 1]	[0 0 255]
white	[1 1 1]	[255 255 255]
black	[0 0 0]	[0 0 0]

Data Types: char | double | single | uint8

target — Target

Figure object | Axes object | PolarAxes object | GeographicAxes object | graphics object

Target, specified as one of these values:

• Figure object. The figure colormap affects plots for all axes within the figure.

• Axes object, PolarAxes object, or GeographicAxes object. You can define a unique colormap for the different axes within a figure.

• Graphics object that has a Colormap property. For example, you can change or query the colormap for a HeatmapChart object.

Output Arguments

cmap — Colormap values

three-column matrix of RGB triplets

Colormap values, returned as a three-column matrix of RGB triplets. Each row of the matrix defines one RGB triplet that specifies one color of the colormap. The values are in the range [0, 1].

More About

Colormap

A colormap is a matrix of values that define the colors for graphics objects such as surface, image, and patch objects. MATLAB^® draws the objects by mapping data values to colors in the colormap.

Colormaps can be any length, but must be three columns wide. Each row in the matrix defines one color using an RGB triplet. An RGB triplet is a three-element row vector whose elements specify the intensities of the red, green, and blue components of the color. Typically, the intensities are double or single values in the range [0, 1]. A value of 0 indicates no color and a value of 1 indicates full intensity. For example, this command creates a colormap that has five colors: black, red, green, blue, and white.

mymap = [0 0 0
    1 0 0
    0 1 0
    0 0 1
    1 1 1];

To change the color scheme of a visualization, call the colormap function to change the colormap of the containing axes or figure. For example, these commands create a surface plot and set the colormap of the figure to mymap.

surf(peaks)
colormap(mymap)

Tips

• To control the limits of the colormap, and how those limits relate to the range of your data, use the caxis function.

Version History

Introduced before R2006a

R2020b: Colormap 'default' option for heatmap displays the blue colormap instead of parula

Setting the colormap on a heatmap chart to 'default' sets the chart's colormap to the default blue colormap for heatmap charts. In R2020a and previous releases, the 'default' option changes the colormap to parula.

To specify the default colormap for a heatmap chart, pass the chart to the colormap function.

h = heatmap(rand(10));
colormap(h,'default')

Only heatmap charts are affected by this change.

R2018a: Setting figure colormap also sets the axes colormap

Starting in R2018a, if you set the colormap for a figure, then axes and charts in the figure use the same colormap. Previously, any axes or chart that you set the colormap for explicitly were unaffected when you set the figure colormap. If you want an Axes object to use a different colormap than the figure, then set the axes colormap after setting the figure colormap.

R2014b: Default colormap changed

• Starting in R2014b, the default colormap is parula. In previous releases, the default colormap was jet.