let p be ProbFinS FinSequence of REAL ; :: thesis: for M being non empty-yielding Conditional_Probability Matrix of REAL st len p = len M holds
Entropy_of_Joint_Prob ((Vec2DiagMx p) * M) = (Entropy p) + (Sum (mlt p,(Entropy_of_Cond_Prob M)))
let M be non empty-yielding Conditional_Probability Matrix of REAL ; :: thesis: ( len p = len M implies Entropy_of_Joint_Prob ((Vec2DiagMx p) * M) = (Entropy p) + (Sum (mlt p,(Entropy_of_Cond_Prob M))) )
assume A1:
len p = len M
; :: thesis: Entropy_of_Joint_Prob ((Vec2DiagMx p) * M) = (Entropy p) + (Sum (mlt p,(Entropy_of_Cond_Prob M)))
set M1 = (Vec2DiagMx p) * M;
len (LineSum (Infor_FinSeq_of M)) =
len (Infor_FinSeq_of M)
by MATRPROB:def 1
.=
len p
by A1, Def8
;
then A2:
( p is Element of (len p) -tuples_on REAL & LineSum (Infor_FinSeq_of M) is Element of (len p) -tuples_on REAL )
by FINSEQ_2:110;
reconsider M1 = (Vec2DiagMx p) * M as Joint_Probability Matrix of REAL by A1, Th28;
A3: Entropy_of_Joint_Prob M1 =
- (Sum (Mx2FinS (Infor_FinSeq_of M1)))
by Th59
.=
- (SumAll (Infor_FinSeq_of M1))
by Th42
.=
- ((Sum (Infor_FinSeq_of p)) + (Sum (mlt p,(LineSum (Infor_FinSeq_of M)))))
by A1, Th64
.=
(- (Sum (Infor_FinSeq_of p))) - (Sum (mlt p,(LineSum (Infor_FinSeq_of M))))
;
(Entropy p) + (Sum (mlt p,(Entropy_of_Cond_Prob M))) =
(- (Sum (Infor_FinSeq_of p))) + (Sum (mlt p,(- (LineSum (Infor_FinSeq_of M)))))
by Th63
.=
(- (Sum (Infor_FinSeq_of p))) + (Sum (- (mlt p,(LineSum (Infor_FinSeq_of M)))))
by A2, RVSUM_1:94
.=
(- (Sum (Infor_FinSeq_of p))) + (- (Sum (mlt p,(LineSum (Infor_FinSeq_of M)))))
by RVSUM_1:118
;
hence
Entropy_of_Joint_Prob ((Vec2DiagMx p) * M) = (Entropy p) + (Sum (mlt p,(Entropy_of_Cond_Prob M)))
by A3; :: thesis: verum