Using rules from Solve
- To: mathgroup at smc.vnet.net
- Subject: [mg33680] Using rules from Solve
- From: post_12 at hotmail.com (postman)
- Date: Sat, 6 Apr 2002 00:48:57 -0500 (EST)
- Sender: owner-wri-mathgroup at wolfram.com
Hey All:
I appreciate any help with the following. I have a working solution,
but don't understand why my first attempt failed. I'm using Solve to
generate solutions to a set of simultaneous equations (the mass action
equations in chemistry), then want to use the resulting solutions to
calculate numerical values for specific values of the parameters.
KdEqn={Kd==R*L/RL, RT=RL+R}
Solve[KdEqn,RL,{RF}] gives me a rule,
{{RL->L*RT/(Kd+L)}}
and Replace[RL,Flatten[Solve[KdEqn,RL,{RF}]]] gives an expression
L*RT/(Kd+L)
that looks like what I would type on the right hand side of a
function:
Rl[L_] := L*RT/(Kd+L)
The problem is that
Rl[L_] := Replace[RL,Flatten[Solve[KdEqn,RP]{Rf}]]
fails; Rl[1] does not substitute the value "1" for "L". However,
Rl[L_] = Replace[RL,Flatten[Solve[KdEqn,RP]{Rf}]]
works as I want. Why does the := construct fail here?
Thanks for any help!