Database
SUPPLEMENTARY MATERIAL (USERS' MATHBOXES)
Mathbox for Thierry Arnoux
Algebra
Vector Space Dimension
df-dim
Metamath Proof Explorer
Description: Define the dimension of a vector space as the cardinality of its bases.
Note that by lvecdim , all bases are equinumerous. (Contributed by Thierry Arnoux , 6-May-2023)
Ref
Expression
Assertion
df-dim
⊢ dim = ( 𝑓 ∈ V ↦ ∪ ( ♯ “ ( LBasis ‘ 𝑓 ) ) )
Detailed syntax breakdown
Step
Hyp
Ref
Expression
0
cldim
⊢ dim
1
vf
⊢ 𝑓
2
cvv
⊢ V
3
chash
⊢ ♯
4
clbs
⊢ LBasis
5
1
cv
⊢ 𝑓
6
5 4
cfv
⊢ ( LBasis ‘ 𝑓 )
7
3 6
cima
⊢ ( ♯ “ ( LBasis ‘ 𝑓 ) )
8
7
cuni
⊢ ∪ ( ♯ “ ( LBasis ‘ 𝑓 ) )
9
1 2 8
cmpt
⊢ ( 𝑓 ∈ V ↦ ∪ ( ♯ “ ( LBasis ‘ 𝑓 ) ) )
10
0 9
wceq
⊢ dim = ( 𝑓 ∈ V ↦ ∪ ( ♯ “ ( LBasis ‘ 𝑓 ) ) )