let A be non empty set ; for L being lower-bounded LATTICE
for d being distance_function of A,L
for Aq being non empty set
for dq being distance_function of Aq,L st Aq,dq is_extension2_of A,d holds
for x, y being Element of A
for a, b being Element of L st d . x,y <= a "\/" b holds
ex z1, z2 being Element of Aq st
( dq . x,z1 = a & dq . z1,z2 = ((d . x,y) "\/" a) "/\" b & dq . z2,y = a )
let L be lower-bounded LATTICE; for d being distance_function of A,L
for Aq being non empty set
for dq being distance_function of Aq,L st Aq,dq is_extension2_of A,d holds
for x, y being Element of A
for a, b being Element of L st d . x,y <= a "\/" b holds
ex z1, z2 being Element of Aq st
( dq . x,z1 = a & dq . z1,z2 = ((d . x,y) "\/" a) "/\" b & dq . z2,y = a )
let d be distance_function of A,L; for Aq being non empty set
for dq being distance_function of Aq,L st Aq,dq is_extension2_of A,d holds
for x, y being Element of A
for a, b being Element of L st d . x,y <= a "\/" b holds
ex z1, z2 being Element of Aq st
( dq . x,z1 = a & dq . z1,z2 = ((d . x,y) "\/" a) "/\" b & dq . z2,y = a )
let Aq be non empty set ; for dq being distance_function of Aq,L st Aq,dq is_extension2_of A,d holds
for x, y being Element of A
for a, b being Element of L st d . x,y <= a "\/" b holds
ex z1, z2 being Element of Aq st
( dq . x,z1 = a & dq . z1,z2 = ((d . x,y) "\/" a) "/\" b & dq . z2,y = a )
let dq be distance_function of Aq,L; ( Aq,dq is_extension2_of A,d implies for x, y being Element of A
for a, b being Element of L st d . x,y <= a "\/" b holds
ex z1, z2 being Element of Aq st
( dq . x,z1 = a & dq . z1,z2 = ((d . x,y) "\/" a) "/\" b & dq . z2,y = a ) )
assume
Aq,dq is_extension2_of A,d
; for x, y being Element of A
for a, b being Element of L st d . x,y <= a "\/" b holds
ex z1, z2 being Element of Aq st
( dq . x,z1 = a & dq . z1,z2 = ((d . x,y) "\/" a) "/\" b & dq . z2,y = a )
then consider q being QuadrSeq of d such that
A1:
Aq = NextSet2 d
and
A2:
dq = NextDelta2 q
by Def11;
let x, y be Element of A; for a, b being Element of L st d . x,y <= a "\/" b holds
ex z1, z2 being Element of Aq st
( dq . x,z1 = a & dq . z1,z2 = ((d . x,y) "\/" a) "/\" b & dq . z2,y = a )
let a, b be Element of L; ( d . x,y <= a "\/" b implies ex z1, z2 being Element of Aq st
( dq . x,z1 = a & dq . z1,z2 = ((d . x,y) "\/" a) "/\" b & dq . z2,y = a ) )
A3:
rng q = { [x9,y9,a9,b9] where x9, y9 is Element of A, a9, b9 is Element of L : d . x9,y9 <= a9 "\/" b9 }
by LATTICE5:def 14;
assume
d . x,y <= a "\/" b
; ex z1, z2 being Element of Aq st
( dq . x,z1 = a & dq . z1,z2 = ((d . x,y) "\/" a) "/\" b & dq . z2,y = a )
then
[x,y,a,b] in rng q
by A3;
then consider o being set such that
A4:
o in dom q
and
A5:
q . o = [x,y,a,b]
by FUNCT_1:def 5;
reconsider o = o as Ordinal by A4;
A6:
q . o = Quadr2 q,o
by A4, Def7;
then A7:
x = (Quadr2 q,o) `1
by A5, MCART_1:78;
A8:
b = (Quadr2 q,o) `4
by A5, A6, MCART_1:78;
A9:
y = (Quadr2 q,o) `2
by A5, A6, MCART_1:78;
reconsider B = ConsecutiveSet2 A,o as non empty set ;
{B} in {{B},{{B}}}
by TARSKI:def 2;
then A10:
{B} in B \/ {{B},{{B}}}
by XBOOLE_0:def 3;
o in DistEsti d
by A4, LATTICE5:28;
then A11:
succ o c= DistEsti d
by ORDINAL1:33;
then A12:
ConsecutiveDelta2 q,(succ o) c= ConsecutiveDelta2 q,(DistEsti d)
by Th25;
reconsider cd = ConsecutiveDelta2 q,o as BiFunction of B,L ;
reconsider Q = Quadr2 q,o as Element of [:B,B,the carrier of L,the carrier of L:] ;
A13:
( x in A & y in A )
;
A14:
{{B}} in {{B},{{B}}}
by TARSKI:def 2;
then A15:
{{B}} in new_set2 B
by XBOOLE_0:def 3;
ConsecutiveSet2 A,(succ o) = new_set2 B
by Th16;
then
new_set2 B c= ConsecutiveSet2 A,(DistEsti d)
by A11, Th22;
then reconsider z1 = {B}, z2 = {{B}} as Element of Aq by A1, A10, A15;
take
z1
; ex z2 being Element of Aq st
( dq . x,z1 = a & dq . z1,z2 = ((d . x,y) "\/" a) "/\" b & dq . z2,y = a )
take
z2
; ( dq . x,z1 = a & dq . z1,z2 = ((d . x,y) "\/" a) "/\" b & dq . z2,y = a )
A16:
cd is zeroed
by Th26;
A c= B
by Th18;
then reconsider xo = x, yo = y as Element of B by A13;
A17:
B c= new_set2 B
by XBOOLE_1:7;
( xo in B & yo in B )
;
then reconsider x1 = xo, y1 = yo as Element of new_set2 B by A17;
A18: ConsecutiveDelta2 q,(succ o) =
new_bi_fun2 (BiFun (ConsecutiveDelta2 q,o),(ConsecutiveSet2 A,o),L),(Quadr2 q,o)
by Th20
.=
new_bi_fun2 cd,Q
by LATTICE5:def 16
;
dom d = [:A,A:]
by FUNCT_2:def 1;
then A19:
[xo,yo] in dom d
by ZFMISC_1:106;
d c= cd
by Th24;
then A20:
cd . xo,yo = d . x,y
by A19, GRFUNC_1:8;
A21:
a = (Quadr2 q,o) `3
by A5, A6, MCART_1:78;
A22:
dom (new_bi_fun2 cd,Q) = [:(new_set2 B),(new_set2 B):]
by FUNCT_2:def 1;
then
[x1,{B}] in dom (new_bi_fun2 cd,Q)
by A10, ZFMISC_1:106;
hence dq . x,z1 =
(new_bi_fun2 cd,Q) . x1,{B}
by A2, A12, A18, GRFUNC_1:8
.=
(cd . xo,xo) "\/" a
by A7, A21, Def5
.=
(Bottom L) "\/" a
by A16, LATTICE5:def 7
.=
a
by WAYBEL_1:4
;
( dq . z1,z2 = ((d . x,y) "\/" a) "/\" b & dq . z2,y = a )
[{B},{{B}}] in dom (new_bi_fun2 cd,Q)
by A10, A15, A22, ZFMISC_1:106;
hence dq . z1,z2 =
(new_bi_fun2 cd,Q) . {B},{{B}}
by A2, A12, A18, GRFUNC_1:8
.=
((d . x,y) "\/" a) "/\" b
by A7, A9, A21, A8, A20, Def5
;
dq . z2,y = a
{{B}} in B \/ {{B},{{B}}}
by A14, XBOOLE_0:def 3;
then
[{{B}},y1] in dom (new_bi_fun2 cd,Q)
by A22, ZFMISC_1:106;
hence dq . z2,y =
(new_bi_fun2 cd,Q) . {{B}},y1
by A2, A12, A18, GRFUNC_1:8
.=
(cd . yo,yo) "\/" a
by A9, A21, Def5
.=
(Bottom L) "\/" a
by A16, LATTICE5:def 7
.=
a
by WAYBEL_1:4
;
verum