Assumptions:
TeX:
\operatorname{csgn}(z) = \begin{cases} \operatorname{sgn}\!\left(\operatorname{Im}(z)\right), & \operatorname{Re}(z) = 0\\\operatorname{sgn}\!\left(\operatorname{Re}(z)\right), & \text{otherwise}\\ \end{cases}
z \in \mathbb{C}Definitions:
| Fungrim symbol | Notation | Short description |
|---|---|---|
| Csgn | Real-valued sign function for complex numbers | |
| Sign | Sign function | |
| Im | Imaginary part | |
| Re | Real part | |
| CC | Complex numbers |
Source code for this entry:
Entry(ID("59a5d6"),
Formula(Equal(Csgn(z), Cases(Tuple(Sign(Im(z)), Equal(Re(z), 0)), Tuple(Sign(Re(z)), Otherwise)))),
Variables(z),
Assumptions(Element(z, CC)))