Metamath Proof Explorer


Definition df-metid

Description: Define the metric identification relation for a pseudometric. (Contributed by Thierry Arnoux, 7-Feb-2018)

Ref Expression
Assertion df-metid ~Met = ( 𝑑 ∈ ∪ ran PsMet ↦ { ⟨ 𝑥 , 𝑦 ⟩ ∣ ( ( 𝑥 ∈ dom dom 𝑑 ∧ 𝑦 ∈ dom dom 𝑑 ) ∧ ( 𝑥 𝑑 𝑦 ) = 0 ) } )

Detailed syntax breakdown

Step Hyp Ref Expression
0 cmetid ⊢ ~Met
1 vd ⊢ 𝑑
2 cpsmet ⊢ PsMet
3 2 crn ⊢ ran PsMet
4 3 cuni ⊢ ∪ ran PsMet
5 vx ⊢ 𝑥
6 vy ⊢ 𝑦
7 5 cv ⊢ 𝑥
8 1 cv ⊢ 𝑑
9 8 cdm ⊢ dom 𝑑
10 9 cdm ⊢ dom dom 𝑑
11 7 10 wcel ⊢ 𝑥 ∈ dom dom 𝑑
12 6 cv ⊢ 𝑦
13 12 10 wcel ⊢ 𝑦 ∈ dom dom 𝑑
14 11 13 wa ⊢ ( 𝑥 ∈ dom dom 𝑑 ∧ 𝑦 ∈ dom dom 𝑑 )
15 7 12 8 co ⊢ ( 𝑥 𝑑 𝑦 )
16 cc0 ⊢ 0
17 15 16 wceq ⊢ ( 𝑥 𝑑 𝑦 ) = 0
18 14 17 wa ⊢ ( ( 𝑥 ∈ dom dom 𝑑 ∧ 𝑦 ∈ dom dom 𝑑 ) ∧ ( 𝑥 𝑑 𝑦 ) = 0 )
19 18 5 6 copab ⊢ { ⟨ 𝑥 , 𝑦 ⟩ ∣ ( ( 𝑥 ∈ dom dom 𝑑 ∧ 𝑦 ∈ dom dom 𝑑 ) ∧ ( 𝑥 𝑑 𝑦 ) = 0 ) }
20 1 4 19 cmpt ⊢ ( 𝑑 ∈ ∪ ran PsMet ↦ { ⟨ 𝑥 , 𝑦 ⟩ ∣ ( ( 𝑥 ∈ dom dom 𝑑 ∧ 𝑦 ∈ dom dom 𝑑 ) ∧ ( 𝑥 𝑑 𝑦 ) = 0 ) } )
21 0 20 wceq ⊢ ~Met = ( 𝑑 ∈ ∪ ran PsMet ↦ { ⟨ 𝑥 , 𝑦 ⟩ ∣ ( ( 𝑥 ∈ dom dom 𝑑 ∧ 𝑦 ∈ dom dom 𝑑 ) ∧ ( 𝑥 𝑑 𝑦 ) = 0 ) } )