Re: extract from Reduce

*To*: mathgroup at smc.vnet.net*Subject*: [mg130356] Re: extract from Reduce*From*: awnl <awnl at gmx-topmail.de>*Date*: Thu, 4 Apr 2013 22:30:55 -0400 (EDT)*Delivered-to*: l-mathgroup@mail-archive0.wolfram.com*Delivered-to*: l-mathgroup@wolfram.com*Delivered-to*: mathgroup-newout@smc.vnet.net*Delivered-to*: mathgroup-newsend@smc.vnet.net*References*: <kjkc5k$7n0$1@smc.vnet.net>

Hi, > I have a result from the command Reduce that looks like this (as an > example): > > a:= x==3||x==4||x==7 > > I need to extract the numbers but I can't find a nice way to handle > the case when there is only one equation, for instance: > > a:= x==6 > > currently I check what the head of the expression is (Head[a]) and > handle the case Head[a]=Or with a Map[] and the case Head[a]="Equal" > with a[[2]]. Not very nice, but I guess that there is a neat way to > do it. > There might be more efficient ways to do this, but I think this is clear and compact: Cases[{a}, Equal[x, v_?NumericQ] :> v, Infinity] hth, albert