Re: LeafCount Question

*To*: mathgroup at smc.vnet.net*Subject*: [mg25802] Re: LeafCount Question*From*: "Hans Staugaard" <hans.staugaard at get2net.dk>*Date*: Sat, 28 Oct 2000 01:40:57 -0400 (EDT)*References*: <8t63s9$eg2@smc.vnet.net>*Sender*: owner-wri-mathgroup at wolfram.com

Hello Here's a quick fix. First a check to see that the ordering is 'wrong': In[1]:= 2c - 2a - b + d Out[1]= -2 a - b + 2 c + d Then my fix In[2]:= Unprotect[Plus]; In[3]:= Format[Plus[negs : (Times[_?Negative, _] ..), poss__]] := SequenceForm[Plus[poss], negs] In[4]:= Protect[Plus]; Now check that the ordering is 'right' In[5]:= 2*c - 2a - b + d Out[5]= 2 c + d-2 a-b Note that there are problems with the operator spacing. Hans "Dana" <dana_news at hotmail.com> wrote in message news:8t63s9$eg2 at smc.vnet.net... > Hello. Using Mathematica 4.0 When one solves equations, I get a little frustrated > when the answers come out as > -A +B, when the answer looks much better as... > B - A > > I was hoping that the "LeafCount" would be smaller with my "preferred" way, > but for some reason, it does not look like there is a difference. > > In[19]:= > {LeafCount[-B + D], LeafCount[D - B]} > > Out[19]= > {5, 5} > > > Here is a simple Solve, and it is a little embarrassing to say the answer is > (-B + D)..Etc when everyone else will have to change this manually to (D - > B)...ect. > > Is there a way around this? Again, I was hoping LeafCount would do the > trick, but it apparently does not. > Thank you in advance. Dana. > > FullSimplify[Solve[{Y == A*X + B, Y == C*X + D}, {X, Y}], > ComplexityFunction -> LeafCount] > > {{X -> (-B + D)/(A - C), Y -> (-(B*C) + A*D)/(A - C)}} > > > > Since I am new to Mathematica, I noticed the following... > Internally, it looks like no difference. It is just frustrating. > > In[25]:= > {FullForm[(-B + D)], FullForm[(D - B)]} > > Out[25]= > {Plus[Times[-1, B], D], Plus[Times[-1, B], D]} > > > >