Why do I receive a "Value must be a handle" error when I modify the "XLabel", "YLabel", "ZLabel", or "Title" property of an axes within MATLAB?

Question

MathWorks Support Team 2012-9-10

编辑： MathWorks Support Team 2018-9-6

When using the following command to set the "XLabel" property of the axes:

set(gca,'Xlabel','This is my label');

I receive an error message:

%BEGIN ERROR%%%

??? Error using ==> set

Value must be a handle.

%END ERROR%%%

Answer 1

Each of the "XLabel", "YLabel", "ZLabel", and "Title" properties of the axes is actually a handle to a text object.

It is recommended to use the XLABEL, YLABEL, ZLABEL, and TITLE functions directly. For example

xlabel('This is my label')

However, if you are required to use the SET function, you can use the following command:

set(get(gca,'XLabel'),'String','This is my label')

For more information about these properties of axes objects, see the following link: