Re: How to remove duplicate solutions (Solve)?

*To*: mathgroup at smc.vnet.net*Subject*: [mg91797] Re: How to remove duplicate solutions (Solve)?*From*: magma <maderri2 at gmail.com>*Date*: Mon, 8 Sep 2008 05:02:44 -0400 (EDT)*References*: <ga24hv$gia$1@smc.vnet.net>

On Sep 8, 5:01 am, Peng Yu <PengYu... at gmail.com> wrote: > Hi, > > Solve[(x - 1)^2 == 0, x] > > The above code would give me the solution > {{x -> 1}, {x -> 1}} > > But one is a duplicate of the other. I'm wondering how to only produce > the unique solutions. > > Thanks, > Peng It is very simple. Solve gives you a list, that is a collection of elements which may be duplicates and have (and have a specific order, but that is not important now). You want to transform this into a set, that is a collection of elements without duplicates. Union does that, among other things. So: In[7]:= Solve[(x - 1)^2 == 0, x] Out[7]= {{x -> 1}, {x -> 1}} In[8]:= Union[%] Out[8]= {{x -> 1}}