# 6.5: Logical Functions

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This is a modified version of Allen B. Downey's section. It was modified by Carey Smith to use parentheses for clarity and to remove possible ambiguity.

The first step is to create a logical function, which is a function that returns a logical value. The following function takes three input variables, a, b, and c, and returns true (1) if they form a Pythagorean triple and false (0) otherwise.

function res = is_pythagorean(a, b, c)
if ( (a^2 + b^2) == c^2)
res = 1;
else
res = 0;
end
end

We can use this function like so:

>> is_pythagorean(3, 4, 5)
ans = 1

Put this function in a file called is_pythagorean.m, so we can use it as part of our program.

This page titled 6.5: Logical Functions is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by Carey Smith via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.