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Fungrim entry: 18d335

sgn⁡(x)={1,x>0−1,x<00,x=0\operatorname{sgn}(x) = \begin{cases} 1, & x > 0\\-1, & x < 0\\0, & x = 0\\ \end{cases}
Assumptions:x∈Rx \in \mathbb{R}
TeX:
\operatorname{sgn}(x) = \begin{cases} 1, & x > 0\\-1, & x < 0\\0, & x = 0\\ \end{cases}

x \in \mathbb{R}
Definitions:
Fungrim symbol Notation Short description
Signsgn⁡(z)\operatorname{sgn}(z) Sign function
RRR\mathbb{R} Real numbers
Source code for this entry:
Entry(ID("18d335"),
    Formula(Equal(Sign(x), Cases(Tuple(1, Greater(x, 0)), Tuple(-1, Less(x, 0)), Tuple(0, Equal(x, 0))))),
    Variables(x),
    Assumptions(Element(x, RR)))

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2021-03-15 19:12:00.328586 UTC