Theorems · Definition · general topology
PiCountable.pseudoEMetricSpace
{ι : Type u_2} →
[Encodable ι] → {F : ι → Type u_3} → [(i : ι) → PseudoEMetricSpace (F i)] → PseudoEMetricSpace ((i : ι) → F i)Given a countable family of extended pseudometric spaces,
one may put an extended distance on their product Π i, E i.
It is highly non-canonical, though, and therefore not registered as a global instance.
The distance we use here is edist x y = ∑' i, min (1/2)^(encode i) (edist (x i) (y i)).
- Defined in
- Mathlib.Topology.MetricSpace.PiNat
- Cited by
- 1 results in Mathlib
- Foundations
- Depth 159 from the axioms · uses propext, Classical.choice, Quot.sound
- Assumes
- EncodablePseudoEMetricSpace
Around this declaration
Dashed lines are statement dependencies; solid lines are citations in proofs.
Cites2
Mathlib declarations this one mentions in its statement or cites explicitly in its proof. Plumbing is filtered out.
- PseudoEMetricSpacestatement and proof · cited by 1,536
- Encodablestatement and proof · cited by 140
Cited by1
Results whose statement or proof uses this declaration.
- Metric.PiNatEmbed.isometry_embedstatement · cited by 1