# Why do I get Parse error ?

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Grégoire on 22 Feb 2024
Edited: Abhinay on 22 Feb 2024
Hi,
I m trying to enter some new functions in my program and i keep getting "Parse error at x : usage might be invalid MATLABsyntax" when defining functions.
This one is an example i don t know what is wrong with it but it won't work
f = (@x) x+2
"invalid expression. Check for missing multipication operator..."
Can some of you help me please?

Dyuman Joshi on 22 Feb 2024
The left parenthesis is supposed to be after the '@' symbol -
f = @(x) x +2
f = function_handle with value:
@(x)x+2
f(3)
ans = 5
The general syntax is
name_of_function = @(independent_variables_separated_by_comma) relation_of_independent_variables
%e.g - function of 3 independent variables
g = @(x,y,z) x + y.*z
%same can be written as
G = @(X,Y,Z) X + Y.*Z
For more information, check out the following documentation pages - Function Handle
Dyuman Joshi on 22 Feb 2024
You forgot to include the multiplication sign between 14 and x.
Note that MATLAB does not support implied multiplication, you have to specify the symbol.
Grégoire on 22 Feb 2024
Okay noted,
thanks a lot for the help :)

Abhinay on 22 Feb 2024
Edited: Abhinay on 22 Feb 2024
I understand that you are getting an error "Parse error at x : usage might be invalid MATLABsyntax" when defining functions when you are trying to enter some new functions in your program.
The error you're seeing is because of a small mistake in the way you've written your function. To fix it, just remove the space between `@` and `(x)`. Here's how it should look:
f = @(x) x + 2;
Use this corrected line in your program, and it should work without the "Parse error".

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