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5.4.1: Function Names and MATLAB Keywords

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    User defined MATLAB function names follow the same rules as variable names:

    The function name must start with a letter.

    It may have numbers and/or an underscore "_"

    It cannot have a space, a hyphen, parentheses, a period, nor another symbol.

    The function filename and the name on the function declaration line (a.k.a. signature) inside the file should be the same. See this link:

    Do not give a user-defined function the same name as a built-in function. That causes a "name collision". You can check the name like this:

    which sum % MATLAB will tell you that this is a built-in function and will display the path to the library which contains this function.

    which my_super_function % MATLAB will tell you that this function is "not found", so it is OK to use as a function name.

    If you give your function the name of a built-in function, you can undo this by renaming your function, then enter this command:

    clear functions

    MATLAB has keywords that are reserved for its own use.
    You cannot use these words as names of variables or functions.
    Entering "iskeyword" gives a list of MATLAB's keywords in alphabetical order:


    This video gives a clear explanation of defining a MATLAB function:

    Section 10.2 reminds us not to create a variable nor a our own function with the same name as a MATLAB function.

    That is, don't create a variable nor a function with a name such as sin, sqrt, 

    This page titled 5.4.1: Function Names and MATLAB Keywords is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by Carey Smith.