Sign Function: Different Representation?

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The discussion centers on the representation of the sign function, commonly denoted as sgn x, defined as f(x) = 1 for x > 0, 0 for x = 0, and -1 for x < 0. A participant queries if there is a specific name for a modified version of this function, which assigns -1 for x ≤ 0 instead of 0. Another contributor suggests that this modified function can be classified as a step function, referencing the Heaviside step function as a related concept. The modified function is humorously referred to as "yahweh" by one participant, indicating a playful take on naming conventions in mathematics. Overall, the conversation explores the nuances of function representation and classification in mathematical terminology.
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For example, the function
f\left( x \right) = \left\{ {\begin{array}{*{20}c}<br /> {1:x &gt; 0} \\<br /> {0:x = 0} \\<br /> { - 1:x &lt; 0} \\<br /> <br /> \end{array} } \right.
is known as the sign function, usually represented as sgn x.

However, is there a specific name for the function
f\left( x \right) = \left\{ {\begin{array}{*{20}c}<br /> {1:x &gt; 0} \\<br /> { - 1:x \leqslant 0} \\<br /> <br /> \end{array} } \right.
?
 
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Well, in that case, my function is simply 2H0(x)-1
:smile:
 
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the name of the function is yahweh.
 
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