let n be non zero Nat; for f being PartFunc of [:(CarProduct ((Seg n) --> RNS_Real)),RNS_Real:],RNS_Real
for g being PartFunc of [:(CarProduct ((Seg n) --> REAL)),REAL:],REAL
for p being Element of CarProduct ((Seg n) --> REAL) st f is_uniformly_continuous_on dom f & f = g holds
ProjPMap1 (g,p) is uniformly_continuous
let f be PartFunc of [:(CarProduct ((Seg n) --> RNS_Real)),RNS_Real:],RNS_Real; for g being PartFunc of [:(CarProduct ((Seg n) --> REAL)),REAL:],REAL
for p being Element of CarProduct ((Seg n) --> REAL) st f is_uniformly_continuous_on dom f & f = g holds
ProjPMap1 (g,p) is uniformly_continuous
let g be PartFunc of [:(CarProduct ((Seg n) --> REAL)),REAL:],REAL; for p being Element of CarProduct ((Seg n) --> REAL) st f is_uniformly_continuous_on dom f & f = g holds
ProjPMap1 (g,p) is uniformly_continuous
let p be Element of CarProduct ((Seg n) --> REAL); ( f is_uniformly_continuous_on dom f & f = g implies ProjPMap1 (g,p) is uniformly_continuous )
assume that
A1:
f is_uniformly_continuous_on dom f
and
A2:
f = g
; ProjPMap1 (g,p) is uniformly_continuous
set P1 = ProjPMap1 (g,p);
for r being Real st 0 < r holds
ex s being Real st
( 0 < s & ( for y1, y2 being Real st y1 in dom (ProjPMap1 (g,p)) & y2 in dom (ProjPMap1 (g,p)) & |.(y1 - y2).| < s holds
|.(((ProjPMap1 (g,p)) . y1) - ((ProjPMap1 (g,p)) . y2)).| < r ) )
proof
let r be
Real;
( 0 < r implies ex s being Real st
( 0 < s & ( for y1, y2 being Real st y1 in dom (ProjPMap1 (g,p)) & y2 in dom (ProjPMap1 (g,p)) & |.(y1 - y2).| < s holds
|.(((ProjPMap1 (g,p)) . y1) - ((ProjPMap1 (g,p)) . y2)).| < r ) ) )
assume
0 < r
;
ex s being Real st
( 0 < s & ( for y1, y2 being Real st y1 in dom (ProjPMap1 (g,p)) & y2 in dom (ProjPMap1 (g,p)) & |.(y1 - y2).| < s holds
|.(((ProjPMap1 (g,p)) . y1) - ((ProjPMap1 (g,p)) . y2)).| < r ) )
then consider s being
Real such that A3:
0 < s
and A4:
for
p1,
p2 being
Point of
[:(CarProduct ((Seg n) --> RNS_Real)),RNS_Real:] st
p1 in dom f &
p2 in dom f &
||.(p1 - p2).|| < s holds
||.((f /. p1) - (f /. p2)).|| < r
by A1;
now for y1, y2 being Real st y1 in dom (ProjPMap1 (g,p)) & y2 in dom (ProjPMap1 (g,p)) & |.(y1 - y2).| < s holds
|.(((ProjPMap1 (g,p)) . y1) - ((ProjPMap1 (g,p)) . y2)).| < rlet y1,
y2 be
Real;
( y1 in dom (ProjPMap1 (g,p)) & y2 in dom (ProjPMap1 (g,p)) & |.(y1 - y2).| < s implies |.(((ProjPMap1 (g,p)) . y1) - ((ProjPMap1 (g,p)) . y2)).| < r )assume that A5:
y1 in dom (ProjPMap1 (g,p))
and A6:
y2 in dom (ProjPMap1 (g,p))
and A7:
|.(y1 - y2).| < s
;
|.(((ProjPMap1 (g,p)) . y1) - ((ProjPMap1 (g,p)) . y2)).| < rA8:
X-section (
(dom g),
p)
= { y where y is Element of REAL : [p,y] in dom g }
by MEASUR11:def 4;
A9:
(
y1 in X-section (
(dom g),
p) &
y2 in X-section (
(dom g),
p) )
by A5, A6, MESFUN12:def 3;
then A10:
ex
y being
Element of
REAL st
(
y = y1 &
[p,y] in dom g )
by A8;
A11:
ex
y being
Element of
REAL st
(
y = y2 &
[p,y] in dom g )
by A8, A9;
reconsider xx =
p as
Point of
(CarProduct ((Seg n) --> RNS_Real)) by MEASUR15:42;
reconsider yy1 =
y1 as
Point of
RNS_Real by XREAL_0:def 1;
reconsider yy2 =
y2 as
Point of
RNS_Real by XREAL_0:def 1;
reconsider p1 =
[xx,yy1],
p2 =
[xx,yy2] as
Point of
[:(CarProduct ((Seg n) --> RNS_Real)),RNS_Real:] ;
A12:
yy1 - yy2 = y1 - y2
by DUALSP03:4;
p1 - p2 = [xx,yy1] + [(- xx),(- yy2)]
by PRVECT_3:18;
then
p1 - p2 = [(xx - xx),(yy1 - yy2)]
by PRVECT_3:18;
then
p1 - p2 = [(0. (CarProduct ((Seg n) --> RNS_Real))),(yy1 - yy2)]
by RLVECT_1:15;
then
||.(p1 - p2).|| = sqrt ((||.(0. (CarProduct ((Seg n) --> RNS_Real))).|| ^2) + (||.(yy1 - yy2).|| ^2))
by NDIFF_8:1;
then
||.(p1 - p2).|| = ||.(yy1 - yy2).||
by SQUARE_1:22;
then
||.(p1 - p2).|| = |.(y1 - y2).|
by A12, EUCLID:def 2;
then A13:
||.((f /. p1) - (f /. p2)).|| < r
by A4, A7, A2, A10, A11;
(
(ProjPMap1 (g,p)) . y1 = g . (
p,
y1) &
(ProjPMap1 (g,p)) . y2 = g . (
p,
y2) )
by A10, A11, MESFUN12:def 3;
then
(
(ProjPMap1 (g,p)) . y1 = f /. p1 &
(ProjPMap1 (g,p)) . y2 = f /. p2 )
by A2, A10, A11, PARTFUN1:def 6;
then
((ProjPMap1 (g,p)) . y1) - ((ProjPMap1 (g,p)) . y2) = (f /. p1) - (f /. p2)
by DUALSP03:4;
hence
|.(((ProjPMap1 (g,p)) . y1) - ((ProjPMap1 (g,p)) . y2)).| < r
by A13, EUCLID:def 2;
verum end;
hence
ex
s being
Real st
(
0 < s & ( for
y1,
y2 being
Real st
y1 in dom (ProjPMap1 (g,p)) &
y2 in dom (ProjPMap1 (g,p)) &
|.(y1 - y2).| < s holds
|.(((ProjPMap1 (g,p)) . y1) - ((ProjPMap1 (g,p)) . y2)).| < r ) )
by A3;
verum
end;
hence
ProjPMap1 (g,p) is uniformly_continuous
by FCONT_2:def 1; verum