Re: reverse the order of replacements in a list of rules
- To: mathgroup at smc.vnet.net
- Subject: [mg105956] Re: [mg105954] reverse the order of replacements in a list of rules
- From: Leonid Shifrin <lshifr at gmail.com>
- Date: Mon, 28 Dec 2009 04:55:23 -0500 (EST)
- References: <200912270746.CAA22055@smc.vnet.net>
Sean,
Here are a couple of ways:
toyrule /. (a_ -> b_) :> (b -> a)
Reverse /@ toyrule
Regards,
Leonid
On Sat, Dec 26, 2009 at 11:46 PM, sean <sean_incali at yahoo.com> wrote:
> Hello group,
>
> This is kinda related with my earlier question about lumping
> parameters. now that I have lumped my parameters, I would like to
> define a new rule that reverses the lumping. I could od it manually,
> but it just seem there should be a better way of doing it..
>
> Suppose you have the following rule for replacing parameters. (in
> lumping, I used up all the letters in alphabet and about half of
> double struck letters. So the actual rule is very long.)
>
> toyrule = {k1 k2 -> a, k3 k4 k5 -> b, k4 k6 k7 -> c, k8 k9/k10 + k11 -
> > d }
>
> and so on and on.
>
> What I want to accomplish is now come up with reverse rule that with
> replace the lumped parameter with primitive parameters.
>
> revtoyrule = {a -> k1 k2, b -> k3 k4 k5 , c-> k4 k6 k7, d-> k8 k9/
> k10 + k11}
>
> And so on.
>
> Thanks much in advance.
>
> Sean
>
>
- References:
- reverse the order of replacements in a list of rules
- From: sean <sean_incali@yahoo.com>
- reverse the order of replacements in a list of rules