Re: solving equations
- To: mathgroup at smc.vnet.net
- Subject: [mg105930] Re: solving equations
- From: bill <bsimpson141421356 at hotmail.com>
- Date: Sat, 26 Dec 2009 19:08:18 -0500 (EST)
- References: <hh16uf$4m4$1@smc.vnet.net>
On Dec 24, 6:10 pm, Maria Davis <arbi... at gmail.com> wrote:
> My file a.txt contains these equations:
>
> x == Csource.receiverRole.RT
> Csource.receiverRole.RT == Csource.sendRole.RT + Csource.TT
> Csource.sendRole.RT == A.inputPort.RT
> A.inputPort.RT == A.outputPort.RT + A.PT
> A.ouputPort.RT == C.receiverRole.RT
> C.receiverRole.RT == C.sendRole.RT + C.TT
> C.sendRole.RT == B.inputPort.RT
> B.inputPort.RT == B.outputPort.RT + B.PT
> B.ouputPort.RT == Csink.receiverRole.RT
> Csink.receiverRole.RT == Csink.sendRole.RT + Csink.TT
> Csink.sendRole.RT == DataSink.inputPort.RT
> DataSink.inputPort.RT == 0
> Csource.TT == 0
> Csink.TT == 0
> C.TT == 0.5
> A.PT == 2
> B.PT == 1.5
>
> For solving these equations for x , I tried to omit the caracter '.',
> because, as certain have adviced, Mathematica interprets the dot as a
> product.
> I replaced the dot by a letter 'a' (for trial) using a code given by
> dr DanW:
>
> dots = ReadList["a.txt", Record, RecordSeparators -> {}]
>
> nodots = StringReplace[dots[[1]], StringExpression
> [pre:LetterCharacter, ".", post:LetterCharacter] :> StringJoin[pre,
> "a", post]]
>
> Solve[ReadList[StringToStream[nodots], Expression], {x}]
>
> I have verified that for example a varible name:
> Csource.receiverRole.RT has changed to CsourceareceiverRoleaRT. But
> the resolution of the system returns a wrong value:
> {{x -> CsourceasendRoleaRT}}
In[1]:=dots=ReadList["a.txt",Record,RecordSeparators->{}];
nodots=StringReplace[dots[[1]],StringExpression
[pre:LetterCharacter,".",post:LetterCharacter]:>StringJoin
[pre,"a",post]];
noouput=StringReplace[nodots,"ouput"->"output"];
Solve[ReadList[StringToStream[noouput],Expression],{x}]
Out[1]={{x->4.}}