Definition:Mapping Preserves Infimum
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Definition
Let $\left({S_1, \preceq_1}\right)$, $\left({S_2, \preceq_2}\right)$ be ordered sets.
Let $f: S_1 \to S_2$ be a mapping.
Mapping Preserves Infimum on Subset
Let $F$ be a subset of $S_1$.
$f$ preserves infimum of $F$ if and only if
- $F$ admits a infimum in $\struct {S_1, \preceq_1}$ implies
- $\map {f^\to} F$ admits an infimum in $\struct {S_2, \preceq_2}$ and $\map \inf {\map {f^\to} F} = \map f {\inf F}$
Mapping Preserves All Infima
$f$ preserves all infima if and only if
- for every subset $F$ of $S_1$, $f$ preserves the infimum of $F$.
Mapping Preserves Meet
$f$ preserves meet if and only if
- for every pair of elements $x, y$ of $S_1$, $f$ preserves the infimum of $\set {x, y}$.
Mapping Preserves Finite Infima
$f$ preserves finite infima if and only if
- for every finite subset $F$ of $S_1$, $f$ preserves the infimum of $F$.
Mapping Preserves Filtered Infima
$f$ preserves filtered infima if and only if
- for every filtered subset $F$ of $S_1$, $f$ preserves the infimum of $F$.