Re: Why does the order of down values come back?
- To: mathgroup at smc.vnet.net
- Subject: [mg124797] Re: Why does the order of down values come back?
- From: David Reiss <dbreiss at gmail.com>
- Date: Tue, 7 Feb 2012 04:03:48 -0500 (EST)
- Delivered-to: l-mathgroup@mail-archive0.wolfram.com
- References: <jgo0e9$a2k$1@smc.vnet.net>
Options[DownValues]={Sort->True} --David On Feb 6, 2:45 am, Shizu <slivo.v... at msa.hinet.net> wrote: > In[]:= f[0] := 0;f[1] := 1;f[n_] := f[n - 1] + f[n - 2] > > In[]:= DownValues[f] > Out[]:= {HoldPattern[f[0]] :> 0, HoldPattern[f[1]] :> 1, HoldPattern[f[n_]] :> f[n - 1] + f[n - 2]} > > In[]:= DownValues[f] = Reverse[DownValues[f]] > Out[]:= {HoldPattern[f[n_]] :> f[n - 1] + f[n - 2], HoldPattern[f[1]] := > 1, HoldPattern[f[0]] :> 0} > > In[]:= DownValues[f] > Out[]:= {HoldPattern[f[0]] :> 0, HoldPattern[f[1]] :> 1, HoldPattern[f[n_]] :> f[n - 1] + f[n - 2]} > > ========================= > My question is: > > Why does the order of down values comes back after reordering? > > Thanks.