Definition:Dual Ordering/Notation
Jump to navigation
Jump to search
Definition
To denote the dual of an ordering, the conventional technique is to reverse the symbol.
Thus:
- $\succeq$ denotes $\preceq^{-1}$
- $\succcurlyeq$ denotes $\preccurlyeq^{-1}$
- $\curlyeqsucc$ denotes $\curlyeqprec^{-1}$
and so:
- $a \preceq b \iff b \succeq a$
- $a \preccurlyeq b \iff b \succcurlyeq a$
- $a \curlyeqprec b \iff b \curlyeqsucc a$
Similarly for the standard symbols used to denote an ordering on numbers:
- $\ge$ denotes $\le^{-1}$
- $\geqslant$ denotes $\leqslant^{-1}$
- $\eqslantgtr$ denotes $\eqslantless^{-1}$
and so on.
Sources
- 1965: Seth Warner: Modern Algebra ... (previous) ... (next): Chapter $\text {III}$: The Natural Numbers: $\S 14$: Orderings