Metamath Proof Explorer


Definition df-sitm

Description: Define the integral metric for simple functions, as the integral of the distances between the function values. Since distances take nonnegative values in RR* , the range structure for this integral is ` ( RR*s |``s ( 0 , +oo ) ) ` . See definition 2.3.1 of Bogachev p. 116. (Contributed by Thierry Arnoux, 22-Oct-2017)

Ref Expression
Assertion df-sitm sitm=wV,mranmeasuresfmw,gmw𝑠*𝑠0+∞fdistwfgdm

Detailed syntax breakdown

Step Hyp Ref Expression
0 csitm classsitm
1 vw setvarw
2 cvv classV
3 vm setvarm
4 cmeas classmeasures
5 4 crn classranmeasures
6 5 cuni classranmeasures
7 vf setvarf
8 1 cv setvarw
9 csitg classsitg
10 3 cv setvarm
11 8 10 9 co classwsitgm
12 11 cdm classmw
13 vg setvarg
14 cxrs class𝑠*
15 cress class𝑠
16 cc0 class0
17 cicc class.
18 cpnf class+∞
19 16 18 17 co class0+∞
20 14 19 15 co class𝑠*𝑠0+∞
21 20 10 9 co class𝑠*𝑠0+∞sitgm
22 7 cv setvarf
23 cds classdist
24 8 23 cfv classdistw
25 24 cof classfdistw
26 13 cv setvarg
27 22 26 25 co classfdistwfg
28 27 21 cfv class𝑠*𝑠0+∞fdistwfgdm
29 7 13 12 12 28 cmpo classfmw,gmw𝑠*𝑠0+∞fdistwfgdm
30 1 3 2 6 29 cmpo classwV,mranmeasuresfmw,gmw𝑠*𝑠0+∞fdistwfgdm
31 0 30 wceq wffsitm=wV,mranmeasuresfmw,gmw𝑠*𝑠0+∞fdistwfgdm