An D548: Ordered pair $G_E = (E, \mathcal{E}_E)$ is a subdigraph of $G_X$ if and only if
| (1) | $E \subseteq X$ | (D78: Subset) |
| (2) | $\mathcal{E}_E \subseteq \mathcal{E}_X$ | (D78: Subset) |
| ▼ | Set of symbols |
| ▼ | Alphabet |
| ▼ | Deduction system |
| ▼ | Theory |
| ▼ | Zermelo-Fraenkel set theory |
| ▼ | Set |
| ▼ | Binary cartesian set product |
| ▼ | Binary relation |
| ▼ | Binary endorelation |
| ▼ | Digraph |
| (1) | $E \subseteq X$ | (D78: Subset) |
| (2) | $\mathcal{E}_E \subseteq \mathcal{E}_X$ | (D78: Subset) |
| ▶ | Set of subdigraphs |
| ▶ | Superdigraph |