Re: Number of digits

*To*: mathgroup at smc.vnet.net*Subject*: [mg73904] Re: Number of digits*From*: Jean-Marc Gulliet <jeanmarc.gulliet at gmail.com>*Date*: Sat, 3 Mar 2007 00:53:24 -0500 (EST)*Organization*: The Open University, Milton Keynes, UK*References*: <es90d7$2f4$1@smc.vnet.net>

Robert Pigeon wrote: > Good afternoon, > How can I force Mathematica to output an answer with a certain number of > significant digits ? What I mean is I want the answer of, let say, 1.0 / 3 > to be output in Mathematica as 0.33 for example. The reason I want to do > that is that I am making a table (using TableForm) of a list of answers to > use in a report. I do not want to see 0.33333 in the table just 0.33 ! > I could use SetPrecision[1./3, 2], but I do not want to do that for every > calculation. I have looked at $MachinePrecision and all other $.... , but I > cannot make sense out of it. > So what I am trying to do, in a nut shell, is do what can be done with a > pocket calculator, set my "visible" answer with a certain number of digits! > > Thanks, > > Robert > > Robert Pigeon > TZ = -5 > > > Use NumberForm to control the display of numbers. In[1]:= NumberForm[x, {3, 2}, NumberPadding -> {"", "0"}] /. x -> 0.123456 Out[1]//NumberForm= 0.12 If you want this by default (rather that 6 decimal digits), you can set the $Post variable as in In[2]:= $Post = NumberForm[#1, {3, 2}, NumberPadding -> {"", "0"}] & Out[2]//NumberForm= Slot[1.00]& In[3]:= 12.1234 Out[3]//NumberForm= 12.10 Regards, Jean-Marc