# Continuous Color Scales and Color Bars in MATLAB®

How to make Continuous Color Scales and Color Bars in MATLAB® with Plotly.

Add a colorbar to a surface plot indicating the color scale.

surf(peaks)
colorbar

fig2plotly(gcf);


By default, the colorbar function adds a vertical colorbar to the right side of the graph.

## Reverse Colorbar Direction

Reverse the direction of values in a colorbar on a graph by setting the 'Direction' property of the colorbar to 'reverse'.

surf(peaks)
colorbar('Direction','reverse')

fig2plotly(gcf);


The colorbar values ascend from top to bottom instead of ascending from bottom to top.

## Display Colorbar Ticks on Opposite Side

Display the colorbar tick marks and tick labels on the side of a colorbar facing the surface plot.

surf(peaks)
colorbar('AxisLocation','in')

fig2plotly(gcf);


## Add Colorbars to Tiled Chart Layout

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. Then display a surface plot in each axes with a colorbar.

tiledlayout(2,1)

% Top plot
nexttile
surf(peaks)
colorbar

% Bottom plot
nexttile
mesh(peaks)
colorbar

fig2plotly(gcf);


## Display Shared Colorbar in Tiled Chart Layout

When you want to share a colorbar between two or more plots, you can display the colorbar in a separate tile of the layout.

Create filled contour plots of the peaks and membrane data sets in a tiled chart layout.

Z1 = peaks;
Z2 = membrane;
tiledlayout(2,1);
nexttile
contourf(Z1)
nexttile
contourf(Z2)

fig2plotly(gcf);


Add a colorbar, and move it to the east tile.

Z1 = peaks;
Z2 = membrane;
tiledlayout(2,1);
nexttile
contourf(Z1)
nexttile
contourf(Z2)

cb = colorbar;
cb.Layout.Tile = 'east';

fig2plotly(gcf);


## Specify Colorbar Ticks and Tick Labels

Add a colorbar to a plot and specify the colorbar tick marks and tick labels. Specify the same number of tick labels as tick marks. If you do not specify enough tick labels, then the colorbar function repeats the labels.

contourf(peaks)
colorbar('Ticks',[-5,-2,1,4,7],...
'TickLabels',{'Cold','Cool','Neutral','Warm','Hot'})

fig2plotly(gcf);


## Label Colorbar

Add a text label along a colorbar.

surf(peaks)
c = colorbar;
c.Label.String = 'Elevation (ft in 1000s)';

fig2plotly(gcf);


## Delete Colorbar

You can delete a colorbar from the surface plot.

surf(peaks)
colorbar
colorbar('off')

fig2plotly(gcf);