Aligning colorbar tick labels and lines in Matlab: A Guide

Initially, the colors are solely blue, but gradually, shades of green are introduced to form cyan and other hues. Thus, if one desires to select the colors manually, they can modify the sequence of colors.


Question:

To create a
plot with a discrete
colorbar
using Matlab, I follow these steps:

data = randi(10, 20);
imagesc(data)
my_colormap = rand(10, 3);
colormap(my_colormap)
cb = colorbar
set(cb,'YTickLabel',{'A';'B';'C';'D';'E';'F';'G';'H';'I';'J';})

The issue at hand is the lack of alignment between the colorbar tick labels and the small lines on the colorbar. A solution is needed to achieve a better alignment, as shown in the accompanying image.


Solution:

The TickLabels on the colorbar correspond to specific values, known as Ticks. Placing the Tick in the center will result in the corresponding TickLabel being displayed in the middle as well. Although it was a bit challenging to make this dynamic and ensure that it remains unchanged when the image is resized, setting the ticks just once is not a difficult task.

set(hCbar,'YTicks',RightYTicks);


EDIT:

If requested, I can provide an example that can serve as a guide.

x = 1:10;
y = 1:10;
cmap = jet(10);
[x, y] = meshgrid(x,y); %x and y grid
c = x-0.1; %Set color code to increase to the right
hFig = figure;
scatter(x(:),y(:),10,c(:),'filled'); % Simpler for the example
set(gca(hFig),'CLim',[0,10]);
colormap(cmap);
hCbar = colorbar;
set(hCbar,'YTicks',0.5:9.5);
set(hCbar,'YTickLabels',{'A','B','C','D','E','F','G','H','I','J'});

In updated versions of Matlab,

YTicks

might have been renamed to

Ticks

, while

YTickLabels

could be referred to as

TickLabels

.

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