set G1 = the _finite non _trivial Tree-like _Graph;
set W = (the_Edges_of the _finite non _trivial Tree-like _Graph) --> 0;
A3:
dom ((the_Edges_of the _finite non _trivial Tree-like _Graph) --> 0) = the_Edges_of the _finite non _trivial Tree-like _Graph
;
A4:
rng ((the_Edges_of the _finite non _trivial Tree-like _Graph) --> 0) c= {0}
by FUNCOP_1:13;
then reconsider W = (the_Edges_of the _finite non _trivial Tree-like _Graph) --> 0 as Function of (the_Edges_of the _finite non _trivial Tree-like _Graph),REAL by A3, FUNCT_2:2;
set G2 = the _finite non _trivial Tree-like _Graph .set (WeightSelector,W);
reconsider EL = {} as PartFunc of (the_Edges_of ( the _finite non _trivial Tree-like _Graph .set (WeightSelector,W))),REAL by RELSET_1:12;
set G3 = ( the _finite non _trivial Tree-like _Graph .set (WeightSelector,W)) .set (ELabelSelector,EL);
reconsider VL = {} as PartFunc of (the_Vertices_of (( the _finite non _trivial Tree-like _Graph .set (WeightSelector,W)) .set (ELabelSelector,EL))),REAL by RELSET_1:12;
set G4 = (( the _finite non _trivial Tree-like _Graph .set (WeightSelector,W)) .set (ELabelSelector,EL)) .set (VLabelSelector,VL);
take
(( the _finite non _trivial Tree-like _Graph .set (WeightSelector,W)) .set (ELabelSelector,EL)) .set (VLabelSelector,VL)
; ( (( the _finite non _trivial Tree-like _Graph .set (WeightSelector,W)) .set (ELabelSelector,EL)) .set (VLabelSelector,VL) is _finite & not (( the _finite non _trivial Tree-like _Graph .set (WeightSelector,W)) .set (ELabelSelector,EL)) .set (VLabelSelector,VL) is _trivial & (( the _finite non _trivial Tree-like _Graph .set (WeightSelector,W)) .set (ELabelSelector,EL)) .set (VLabelSelector,VL) is Tree-like & (( the _finite non _trivial Tree-like _Graph .set (WeightSelector,W)) .set (ELabelSelector,EL)) .set (VLabelSelector,VL) is nonnegative-weighted & (( the _finite non _trivial Tree-like _Graph .set (WeightSelector,W)) .set (ELabelSelector,EL)) .set (VLabelSelector,VL) is real-WEV )
thus
( (( the _finite non _trivial Tree-like _Graph .set (WeightSelector,W)) .set (ELabelSelector,EL)) .set (VLabelSelector,VL) is _finite & not (( the _finite non _trivial Tree-like _Graph .set (WeightSelector,W)) .set (ELabelSelector,EL)) .set (VLabelSelector,VL) is _trivial & (( the _finite non _trivial Tree-like _Graph .set (WeightSelector,W)) .set (ELabelSelector,EL)) .set (VLabelSelector,VL) is Tree-like )
; ( (( the _finite non _trivial Tree-like _Graph .set (WeightSelector,W)) .set (ELabelSelector,EL)) .set (VLabelSelector,VL) is nonnegative-weighted & (( the _finite non _trivial Tree-like _Graph .set (WeightSelector,W)) .set (ELabelSelector,EL)) .set (VLabelSelector,VL) is real-WEV )
A5: the_Weight_of ((( the _finite non _trivial Tree-like _Graph .set (WeightSelector,W)) .set (ELabelSelector,EL)) .set (VLabelSelector,VL)) =
(( the _finite non _trivial Tree-like _Graph .set (WeightSelector,W)) .set (ELabelSelector,EL)) . WeightSelector
by GLIB_000:9
.=
( the _finite non _trivial Tree-like _Graph .set (WeightSelector,W)) . WeightSelector
by GLIB_000:9
.=
W
by GLIB_000:8
;
for x being object st x in {0} holds
x in Real>=0
by GRAPH_5:def 12;
then
{0} c= Real>=0
by TARSKI:def 3;
then
rng W c= Real>=0
by A4, XBOOLE_1:1;
hence
(( the _finite non _trivial Tree-like _Graph .set (WeightSelector,W)) .set (ELabelSelector,EL)) .set (VLabelSelector,VL) is nonnegative-weighted
by A5; (( the _finite non _trivial Tree-like _Graph .set (WeightSelector,W)) .set (ELabelSelector,EL)) .set (VLabelSelector,VL) is real-WEV
the_ELabel_of ((( the _finite non _trivial Tree-like _Graph .set (WeightSelector,W)) .set (ELabelSelector,EL)) .set (VLabelSelector,VL)) =
(( the _finite non _trivial Tree-like _Graph .set (WeightSelector,W)) .set (ELabelSelector,EL)) . ELabelSelector
by GLIB_000:9
.=
EL
by GLIB_000:8
;
then A6:
(( the _finite non _trivial Tree-like _Graph .set (WeightSelector,W)) .set (ELabelSelector,EL)) .set (VLabelSelector,VL) is real-elabeled
;
(( the _finite non _trivial Tree-like _Graph .set (WeightSelector,W)) .set (ELabelSelector,EL)) .set (VLabelSelector,VL) is real-weighted
by A5;
hence
(( the _finite non _trivial Tree-like _Graph .set (WeightSelector,W)) .set (ELabelSelector,EL)) .set (VLabelSelector,VL) is real-WEV
by A6; verum