Metamath Proof Explorer


Definition df-ismty

Description: Define a function which takes two metric spaces and returns the set of isometries between the spaces. An isometry is a bijection which preserves distance. (Contributed by Jeff Madsen, 2-Sep-2009)

Ref Expression
Assertion df-ismty Ismty=mran∞Met,nran∞Metf|f:domdomm1-1 ontodomdomnxdomdommydomdommxmy=fxnfy

Detailed syntax breakdown

Step Hyp Ref Expression
0 cismty classIsmty
1 vm setvarm
2 cxmet class∞Met
3 2 crn classran∞Met
4 3 cuni classran∞Met
5 vn setvarn
6 vf setvarf
7 6 cv setvarf
8 1 cv setvarm
9 8 cdm classdomm
10 9 cdm classdomdomm
11 5 cv setvarn
12 11 cdm classdomn
13 12 cdm classdomdomn
14 10 13 7 wf1o wfff:domdomm1-1 ontodomdomn
15 vx setvarx
16 vy setvary
17 15 cv setvarx
18 16 cv setvary
19 17 18 8 co classxmy
20 17 7 cfv classfx
21 18 7 cfv classfy
22 20 21 11 co classfxnfy
23 19 22 wceq wffxmy=fxnfy
24 23 16 10 wral wffydomdommxmy=fxnfy
25 24 15 10 wral wffxdomdommydomdommxmy=fxnfy
26 14 25 wa wfff:domdomm1-1 ontodomdomnxdomdommydomdommxmy=fxnfy
27 26 6 cab classf|f:domdomm1-1 ontodomdomnxdomdommydomdommxmy=fxnfy
28 1 5 4 4 27 cmpo classmran∞Met,nran∞Metf|f:domdomm1-1 ontodomdomnxdomdommydomdommxmy=fxnfy
29 0 28 wceq wffIsmty=mran∞Met,nran∞Metf|f:domdomm1-1 ontodomdomnxdomdommydomdommxmy=fxnfy