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Re: NDSolve

  • To: mathgroup at smc.vnet.net
  • Subject: [mg43092] Re: NDSolve
  • From: "Steffen" <nnnx at gmx.de>
  • Date: Tue, 12 Aug 2003 04:43:06 -0400 (EDT)
  • Organization: University of Karlsruhe, Germany
  • References: <bgctse$9l9$1@smc.vnet.net> <bgfrpc$lf5$1@smc.vnet.net>
  • Sender: owner-wri-mathgroup at wolfram.com

"Bill Bertram" <wkb at ansto.gov.au> schrieb im Newsbeitrag
news:bgfrpc$lf5$1 at smc.vnet.net...
>
> "Steffen" <nnnx at gmx.de> wrote in message news:bgctse$9l9$1 at smc.vnet.net...
> > Hi all,
> > unfortunately Mathematica is not able to solve the following:
> >
> > NDSolve[{
> >
> > y1'[x] == -k1 y1[x] y2[x] + km1 y3[x],
> >
> > y2'[x] == -k1 y1[x] y2[x] + km1 y3[x],
> >
> > y3'[x] == k1 y1[x] y2[x] + km2 y4[x] M - (km1 + k2 M) y3[x],
> >
> > y4'[x] == -km2 M y4[x] + k2 M y3[x],
> >
> > y1[0] = 10^13,
> >
> > y2[0] = 10^16,
> >
> > y3[0] = 0,
> >
> > y4[0] = 0,
> >
> > } , {y1 , y2 , y3 , y4} , {x , 0 , 50 10^-6}]
> >
>
> Hi,
>
> Replace the single "=" signs by double "==" . Also remove the comma after
> y4[0]=0.
> Now, if you assign values to all of your constants you should be OK.
> Cheers,
>  Bill
>
>

Hi Bill,

sorry for answering late, but I have had three days of vaccation.
Of course there were double "=" in the equation system. Also the commata was
missing in my mathematica file. But anyhow it doesn´t work.



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