# Built-in Continuous Color Scales in MATLAB®

How to use Built-in Continuous Color Scales in MATLAB® with Plotly.

## Change Colormap for Figure

Create a surface plot and set the colormap to winter.

surf(peaks)
colormap winter

fig2plotly(gcf);


## Set Colormap Back to Default

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

surf(peaks)
colormap summer

fig2plotly(gcf);


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.

surf(peaks)
colormap default

fig2plotly(gcf);


## 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)

fig2plotly(gcf);


## 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))

fig2plotly(gcf);


## 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)

fig2plotly(gcf);


## Return Colormap Values Used in Plot

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

mesh(peaks)
colormap(autumn(5))

fig2plotly(gcf);


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.

mesh(peaks)
colormap(autumn(5))

cmap = colormap

cmap =

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)

fig2plotly(gcf);