:: Ternary Fields
:: by Micha{\l} Muzalewski and Wojciech Skaba
::
:: Received October 15, 1990
:: Copyright (c) 1990 Association of Mizar Users

definition

attr c₁ is strict;
struct TernaryFieldStr -> ZeroOneStr ;
aggr TernaryFieldStr(# carrier, ZeroF, OneF, TernOp #) -> TernaryFieldStr ;
sel TernOp c₁ -> TriOp of the carrier of c₁;

end;

registration

cluster non empty TernaryFieldStr ;
existence
not for b₁ being TernaryFieldStr holds b₁ is empty

proof end;

end;

definition

let F be non empty TernaryFieldStr ;
mode Scalar of F is Element of F;

end;

definition

let F be non empty TernaryFieldStr ;
let a, b, c be Scalar of F;
func Tern a,b,c -> Scalar of F equals :: ALGSTR_3:def 1
the TernOp of F . a,b,c;
correctness
coherence
the TernOp of F . a,b,c is Scalar of F;
;

end;

:: deftheorem defines Tern ALGSTR_3:def 1 :

for F being non empty TernaryFieldStr
for a, b, c being Scalar of F holds Tern a,b,c = the TernOp of F . a,b,c;

definition

canceled;
canceled;
func ternaryreal -> TriOp of REAL means :Def4: :: ALGSTR_3:def 4
for a, b, c being Real holds it . a,b,c = (a * b) + c;
existence
ex b₁ being TriOp of REAL st
for a, b, c being Real holds b₁ . a,b,c = (a * b) + c

proof end;

uniqueness
for b₁, b₂ being TriOp of REAL st ( for a, b, c being Real holds b₁ . a,b,c = (a * b) + c ) & ( for a, b, c being Real holds b₂ . a,b,c = (a * b) + c ) holds
b₁ = b₂

proof end;

end;

:: deftheorem ALGSTR_3:def 2 :

canceled;

:: deftheorem ALGSTR_3:def 3 :

canceled;

:: deftheorem Def4 defines ternaryreal ALGSTR_3:def 4 :

for b₁ being TriOp of REAL holds
( b₁ = ternaryreal iff for a, b, c being Real holds b₁ . a,b,c = (a * b) + c );

definition

func TernaryFieldEx -> strict TernaryFieldStr equals :: ALGSTR_3:def 5
TernaryFieldStr(# REAL ,0 ,1,ternaryreal #);
correctness
coherence
TernaryFieldStr(# REAL ,0 ,1,ternaryreal #) is strict TernaryFieldStr ;
;

end;

:: deftheorem defines TernaryFieldEx ALGSTR_3:def 5 :

TernaryFieldEx = TernaryFieldStr(# REAL ,0 ,1,ternaryreal #);

registration

cluster TernaryFieldEx -> non empty strict ;
coherence
not TernaryFieldEx is empty ;

end;

definition

let a, b, c be Scalar of TernaryFieldEx ;
func tern a,b,c -> Scalar of TernaryFieldEx equals :: ALGSTR_3:def 6
the TernOp of TernaryFieldEx . a,b,c;
correctness
coherence
the TernOp of TernaryFieldEx . a,b,c is Scalar of TernaryFieldEx ;
;

end;

:: deftheorem defines tern ALGSTR_3:def 6 :

for a, b, c being Scalar of TernaryFieldEx holds tern a,b,c = the TernOp of TernaryFieldEx . a,b,c;

theorem :: ALGSTR_3:1

canceled;

theorem :: ALGSTR_3:2

canceled;

theorem Th3: :: ALGSTR_3:3

for u, u', v, v' being Real st u <> u' holds
ex x being Real st (u * x) + v = (u' * x) + v'

proof end;

theorem :: ALGSTR_3:4

canceled;

theorem :: ALGSTR_3:5

for u, a, v being Scalar of TernaryFieldEx
for z, x, y being Real st u = z & a = x & v = y holds
Tern u,a,v = (z * x) + y by Def4;

theorem :: ALGSTR_3:6

canceled;

theorem :: ALGSTR_3:7

1 = 1. TernaryFieldEx ;

Lm1: for a being Scalar of TernaryFieldEx holds Tern a,(1. TernaryFieldEx ),(0. TernaryFieldEx ) = a

proof end;

Lm2: for a being Scalar of TernaryFieldEx holds Tern (1. TernaryFieldEx ),a,(0. TernaryFieldEx ) = a

proof end;

Lm3: for a, b being Scalar of TernaryFieldEx holds Tern a,(0. TernaryFieldEx ),b = b

proof end;

Lm4: for a, b being Scalar of TernaryFieldEx holds Tern (0. TernaryFieldEx ),a,b = b

proof end;

Lm5: for u, a, b being Scalar of TernaryFieldEx ex v being Scalar of TernaryFieldEx st Tern u,a,v = b

proof end;

Lm6: for u, a, v, v' being Scalar of TernaryFieldEx st Tern u,a,v = Tern u,a,v' holds
v = v'

proof end;

Lm7: for a, a' being Scalar of TernaryFieldEx st a <> a' holds
for b, b' being Scalar of TernaryFieldEx ex u, v being Scalar of TernaryFieldEx st
( Tern u,a,v = b & Tern u,a',v = b' )

proof end;

Lm8: for u, u' being Scalar of TernaryFieldEx st u <> u' holds
for v, v' being Scalar of TernaryFieldEx ex a being Scalar of TernaryFieldEx st Tern u,a,v = Tern u',a,v'

proof end;

Lm9: for a, a', u, u', v, v' being Scalar of TernaryFieldEx st Tern u,a,v = Tern u',a,v' & Tern u,a',v = Tern u',a',v' & not a = a' holds
u = u'

proof end;

definition

let IT be non empty TernaryFieldStr ;
attr IT is Ternary-Field-like means :Def7: :: ALGSTR_3:def 7
( 0. IT <> 1. IT & ( for a being Scalar of IT holds Tern a,(1. IT),(0. IT) = a ) & ( for a being Scalar of IT holds Tern (1. IT),a,(0. IT) = a ) & ( for a, b being Scalar of IT holds Tern a,(0. IT),b = b ) & ( for a, b being Scalar of IT holds Tern (0. IT),a,b = b ) & ( for u, a, b being Scalar of IT ex v being Scalar of IT st Tern u,a,v = b ) & ( for u, a, v, v' being Scalar of IT st Tern u,a,v = Tern u,a,v' holds
v = v' ) & ( for a, a' being Scalar of IT st a <> a' holds
for b, b' being Scalar of IT ex u, v being Scalar of IT st
( Tern u,a,v = b & Tern u,a',v = b' ) ) & ( for u, u' being Scalar of IT st u <> u' holds
for v, v' being Scalar of IT ex a being Scalar of IT st Tern u,a,v = Tern u',a,v' ) & ( for a, a', u, u', v, v' being Scalar of IT st Tern u,a,v = Tern u',a,v' & Tern u,a',v = Tern u',a',v' & not a = a' holds
u = u' ) );

end;

:: deftheorem Def7 defines Ternary-Field-like ALGSTR_3:def 7 :

for IT being non empty TernaryFieldStr holds
( IT is Ternary-Field-like iff ( 0. IT <> 1. IT & ( for a being Scalar of IT holds Tern a,(1. IT),(0. IT) = a ) & ( for a being Scalar of IT holds Tern (1. IT),a,(0. IT) = a ) & ( for a, b being Scalar of IT holds Tern a,(0. IT),b = b ) & ( for a, b being Scalar of IT holds Tern (0. IT),a,b = b ) & ( for u, a, b being Scalar of IT ex v being Scalar of IT st Tern u,a,v = b ) & ( for u, a, v, v' being Scalar of IT st Tern u,a,v = Tern u,a,v' holds
v = v' ) & ( for a, a' being Scalar of IT st a <> a' holds
for b, b' being Scalar of IT ex u, v being Scalar of IT st
( Tern u,a,v = b & Tern u,a',v = b' ) ) & ( for u, u' being Scalar of IT st u <> u' holds
for v, v' being Scalar of IT ex a being Scalar of IT st Tern u,a,v = Tern u',a,v' ) & ( for a, a', u, u', v, v' being Scalar of IT st Tern u,a,v = Tern u',a,v' & Tern u,a',v = Tern u',a',v' & not a = a' holds
u = u' ) ) );

registration

cluster non empty strict Ternary-Field-like TernaryFieldStr ;
existence
ex b₁ being non empty TernaryFieldStr st
( b₁ is strict & b₁ is Ternary-Field-like )

proof end;

end;

definition

mode Ternary-Field is non empty Ternary-Field-like TernaryFieldStr ;

end;

theorem :: ALGSTR_3:8

for F being Ternary-Field
for a, a', u, v, u', v' being Scalar of F st a <> a' & Tern u,a,v = Tern u',a,v' & Tern u,a',v = Tern u',a',v' holds
( u = u' & v = v' )

proof end;

theorem :: ALGSTR_3:9

canceled;

theorem :: ALGSTR_3:10

canceled;

theorem :: ALGSTR_3:11

for F being Ternary-Field
for a being Scalar of F st a <> 0. F holds
for b, c being Scalar of F ex x being Scalar of F st Tern a,x,b = c

proof end;

theorem :: ALGSTR_3:12

for F being Ternary-Field
for a, x, b, x' being Scalar of F st a <> 0. F & Tern a,x,b = Tern a,x',b holds
x = x'

proof end;

theorem :: ALGSTR_3:13

for F being Ternary-Field
for a being Scalar of F st a <> 0. F holds
for b, c being Scalar of F ex x being Scalar of F st Tern x,a,b = c

proof end;

theorem :: ALGSTR_3:14

for F being Ternary-Field
for a, x, b, x' being Scalar of F st a <> 0. F & Tern x,a,b = Tern x',a,b holds
x = x'

proof end;