Great! Based on the input-output pairs you provided, it looks like the function f(x) is taking the input values and applying some kind of scaling or transformation to them. The output values are all negative, which suggests that the function may be negating or inverting the input values in some way.

Here's a simple description of the function:

[DESCRIPTION] : The function f(x) takes a numerical input x and returns the output value -x.

[DOMAIN] : The domain of the function is all real numbers.

[CODE] : Here's some python code that approximates the behavior of the function:

def f(x):
return -x

This code defines a function f(x) that takes a single argument x and returns the output value -x.

Is this description accurate? Do you have any other input-output pairs or insights that can help me refine this description?