How to modify multiple rules in a single list

Question

How can I modify multiple rules simultaneously in a single list of rules? Right now I generate two lists, where both rules are replaced with the same value in each single list. But what I want is the result at the bottom. One replaced list with both elements updated accordingly. I know that the table is going to give me two separate list, however that is as close as I have gotten thus far.

parameterNamesThreadedThroughNumericList = {k1p -> 0.034859, 
k1m -> 86.3298, k2p -> 0.12406, k2m -> 79.72530, pfb -> 9.70214, 
k3p -> 0.016358, k3m -> 18.5253, k4p -> 4.53765, k4m -> 28.02712, 
k5p -> 1.17405, k5m -> 41.91223, k6p -> 9.86758, k6m -> 51.70695, 
kn -> 1.06146, kc -> 0.02758, k8p -> 2.20933, k8m -> 82.13274, 
k9p -> 10.47200, k9m -> 90.98189, nfbs -> 0.08481, nfbX -> 3.58059, 
state -> 1.}
alternativeParameterLists = {state -> 0., pfb -> .5};
Table[parameterNamesThreadedThroughNumericList //.
   Rule[p : Alternatives @@ 
  alternativeParameterLists[[All, 1]], _] :> 
   Rule[p, alternativeParameterLists[[i, 2]]*alternativeParameterLists[[i, 1]] /. 
 parameterNamesThreadedThroughNumericList
     ],{i, 1, 2, 1}]

{{k1p -> 0.034859, k1m -> 86.3298, k2p -> 0.12406, k2m -> 79.7253, 
 pfb -> 0., k3p -> 0.016358, k3m -> 18.5253, k4p -> 4.53765, 
 k4m -> 28.0271, k5p -> 1.17405, k5m -> 41.9122, k6p -> 9.86758, 
 k6m -> 51.707, kn -> 1.06146, kc -> 0.02758, k8p -> 2.20933, 
 k8m -> 82.1327, k9p -> 10.472, k9m -> 90.9819, nfbs -> 0.08481, 
 nfbX -> 3.58059, state -> 0.},
 {k1p -> 0.034859, k1m -> 86.3298, 
 k2p -> 0.12406, k2m -> 79.7253, pfb -> 4.85107, k3p -> 0.016358, 
 k3m -> 18.5253, k4p -> 4.53765, k4m -> 28.0271, k5p -> 1.17405, 
 k5m -> 41.9122, k6p -> 9.86758, k6m -> 51.707, kn -> 1.06146, 
 kc -> 0.02758, k8p -> 2.20933, k8m -> 82.1327, k9p -> 10.472, 
 k9m -> 90.9819, nfbs -> 0.08481, nfbX -> 3.58059, state -> 4.85107}}

{k1p -> 0.034859, 
k1m -> 86.3298, k2p -> 0.12406, k2m -> 79.72530, pfb -> 4.85107, 
k3p -> 0.016358, k3m -> 18.5253, k4p -> 4.53765, k4m -> 28.02712, 
k5p -> 1.17405, k5m -> 41.91223, k6p -> 9.86758, k6m -> 51.70695, 
kn -> 1.06146, kc -> 0.02758, k8p -> 2.20933, k8m -> 82.13274, 
k9p -> 10.47200, k9m -> 90.98189, nfbs -> 0.08481, nfbX -> 3.58059, 
state -> 0.}

I've seen that this question is related to How to replace multiple variables at once However, because I am replacing old rules with new rules based on parts of the expression I believe it is different enough to be considered unique.

Related: (4332), (60913), (61655) – Mr.Wizard Oct 09 '16 at 18:42 — Mr.Wizard, Oct 09 '16 at 18:42

kglr · Accepted Answer · 2016-10-09T19:10:50.633

4

Normal@Merge[{parameterNamesThreadedThroughNumericList, alternativeParameterLists}, 
 Times @@ # &]

or

Normal@Merge[Times@@#&][{parameterNamesThreadedThroughNumericList, 
   alternativeParameterLists}]

both give

{k1p -> 0.034859, k1m -> 86.3298, k2p -> 0.12406, k2m -> 79.7253, pfb -> 4.85107, k3p -> 0.016358, k3m -> 18.5253, k4p -> 4.53765, k4m -> 28.0271, k5p -> 1.17405, k5m -> 41.9122, k6p -> 9.86758, k6m -> 51.707, kn -> 1.06146, kc -> 0.02758, k8p -> 2.20933, k8m -> 82.1327, k9p -> 10.472, k9m -> 90.9819, nfbs -> 0.08481, nfbX -> 3.58059, state -> 0.}

edited Oct 09 '16 at 19:10

answered Oct 09 '16 at 17:44

kglr

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You don't even need to convert to Association first. +1 of course. – Mr.Wizard Oct 09 '16 at 18:37
Thank you @Mr.Wizard. I didn't know Merge worked with lists of rules. – kglr Oct 09 '16 at 19:12
This is much cleaner than the approach than I was taking. The original code was written pre-Associations. This is motivation enough to port the whole package to a newer version. – tarhawk Oct 11 '16 at 20:14

How to modify multiple rules in a single list

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