What's the difference between operators and functions?

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Operators and functions are fundamentally related, with operators often considered a specific type of function. A binary operation on a set can be viewed as a function from the Cartesian product of that set to itself. Infix notation, like x + y, is used for convenience, while functions can also be expressed in prefix form, such as +(x, y). Operators typically refer to functions that act on other functions, distinguishing them from operations that act directly on numbers. The distinction between operators and operations can sometimes lead to ambiguity in mathematical texts.
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Is there a fundamental difference between operators and functions?

For example we could have F(x,y)=x+y or we could write SUM(x,y) where SUM is a defined operation in some program. Could operators be considered a particular type of function?
 
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Yes. Any binary operation on S is simpy a function from S \times S \to S. We use infix notation (that is, we write the function in between the operands as in x + y instead of +(x, y) ) out of convenience and familiarity.
 
Moo Of Doom said:
Yes. Any binary operation on S is simpy a function from S \times S \to S. We use infix notation (that is, we write the function in between the operands as in x + y instead of +(x, y) ) out of convenience and familiarity.

Thanks Moo Of Doom. I was pretty sure of this, but math texts usually use these in terms in distinct ways.
 
Last edited:
Moo of Doom talked about "operations". Your question was about "operators". Generally, an "operator" is a function defined on functions as opposed to functions on numbers.
 
HallsofIvy said:
Moo of Doom talked about "operations". Your question was about "operators". Generally, an "operator" is a function defined on functions as opposed to functions on numbers.

Then SUM(x,y) would not be read as an operator on (x,y), but rather as an operation on (x,y)?
 
Yes, that is true. The original post was ambiguous.
 
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