What Is UDF

User-defined functions, or UDFs, are AUX functions stored in .aux files. In auxlab2, a UDF is typically loaded from disk, registered with the engine, and then called by its file name without the .aux extension.

Basic Form

A simple UDF file can start with a function definition like this:

function y = myudf(x)
y = x.sqrt

If this is saved as myudf.aux and the file is loaded, you can call it as:

out = myudf([1 4 9 16])

Multiple Outputs

A UDF can return more than one output.

function [sumv, diffv] = pair_ops(a, b)
sumv = a + b
diffv = a - b

Usage:

[s, d] = pair_ops(10, 3)

Member Functions

The current codebase also supports member-style UDF definitions.

member function out = myfunc(arg)
out = name ++ sprintf("%d", id)

This form is useful when the function is meant to operate in a member-call context.

Working With UDF Files In auxlab2

In the current auxlab2 application:

• choose File > Open UDF... to load a .aux file
• the file name stem becomes the UDF name used for calls
• the current file can also be reopened quickly from the recent-UDF list
• when a watched UDF file changes on disk, auxlab2 can reload it

Under the hood, the app loads the file path, defines the UDF, and then registers it with the AUX engine.

Notes

• The file name matters. A file named myudf.aux is expected to register as myudf.
• UDFs are part of the canonical help gap noted in the older documentation, so this page should keep growing as we verify more syntax details.
• For debugging a UDF in the current app, see Debugging UDFs.

Current source basis:

• auxlab2/src/AuxEngineFacade.cpp
• auxlab2/src/MainWindow.cpp
• aux_engine/example_apps/aux2/myudf.aux
• auxlab2/myfunc.aux