# How can I fix my function?

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Matlab Student on 19 Sep 2021
Commented: Walter Roberson on 22 Sep 2021
Hi, I'm new to Matlab and have a lot of difficulty understanding how to properly write functions. I need to write a function ispythag that will recieve three positive integers (a,b,c) that will return a logical 1 if they form a pythagorean triple, or logical 0 if they don't. I also cannot use if or select statements.This is the code I have written but I always get an error saying unrecognized function or variable 'a', however when I write a script using this code and write "ispythag(1,2,3)" or "ispythag(3,4,5)" in the command prompt, I get the logical answers I need. After several attempts at changing my code without success, I was hoping someone might be able to lend me some guidance. Thank you very much for your time and help!
Ptriple = ispythag(a,b,c)
Ptriple = a^2+b^2 == c^2;
ispythag(1,2,3)
ispythag(3,4,5)
Cris LaPierre on 20 Sep 2021
You have not property declared your function. See this page for help with that. It also contains some working examples that you can modify to get your function started.

Wan Ji on 20 Sep 2021
Hey， friend
Just try the inline function
ispythag = @(a,b,c)a.^2+b.^2 == c.^2;
a = ispythag(1,2,3)
b = ispythag(3,4,5)
Then you will obtain the result
a =
logical
0
b =
logical
1
Matlab Student on 22 Sep 2021
Thank you ver much for your help. Just a quick follow up question, why do i need to include the '@' in the function?
Walter Roberson on 22 Sep 2021
The correct term for this in MATLAB is "anonymous function". It is documented at https://www.mathworks.com/help/matlab/matlab_prog/anonymous-functions.html
MATLAB does have "inline" functions as well, which are not recommended; they are an older technology that has a number of drawbacks compared to anonymous functions.