: It looks at the first argument in the list. It checks if that argument is a valid graphics handle of type axes (or a related object like a uifigure in modern MATLAB).
In the world of MATLAB programming, creating robust graphical functions is an art. If you've ever looked at the source code of built-in plotting functions like plot , surf , or bar , you might have stumbled upon a utility function called . While it isn't a function most casual users will ever call directly, it is a cornerstone for developers building professional-grade MATLAB tools. What is axescheck ?
), axescheck returns an empty value for the axes handle and keeps the input list intact. Why Use It? (The Developer's Perspective) axescheck
The challenge for the developer is that ax is just a variable. Without a specialized check, your code might confuse an axes handle for a data vector. This is where axescheck saves the day. How It Works: The Logic of Input Parsing
In the era of , axescheck has become even more relevant. When building apps, you almost always want to point your plotting functions to a specific UIAxes component within the app UI rather than letting them "pop out" into a new figure window. Including axescheck in your internal library functions makes them "App-ready" by default. Conclusion : It looks at the first argument in the list
axescheck is a perfect example of MATLAB’s "hidden" infrastructure—the code that makes the software feel intuitive and consistent. While you might not use it to solve a math problem, using it in your toolbox development marks the transition from a script writer to a software toolbuilder.
: If the first argument is not an axes handle (e.g., it's just your data If you've ever looked at the source code
: Manually checking isa(varargin{1}, 'matlab.graphics.axis.Axes') is tedious and error-prone, especially when dealing with empty inputs or different types of containers.
plot(ax, y) — Plots specifically in the axes defined by the handle ax .
If you are writing a custom plotting utility, using axescheck ensures your function feels like a native part of the MATLAB ecosystem.