Re: About N in Mathematica 4

*To*: mathgroup at smc.vnet.net*Subject*: [mg25383] Re: [mg25327] About N in Mathematica 4*From*: "Rosa Ma. Seco" <ceie at prodigy.net.mx>*Date*: Fri, 29 Sep 2000 01:06:14 -0400 (EDT)*Sender*: owner-wri-mathgroup at wolfram.com

This is a recurring question. You must bear in mind the distinction between the number of digits Mathematica is using internally, and the number of digits it is showing on your display. NumberForm[expr, n] prints with approximate real numbers in expr given to ndigit precision. In[1]:= Table[NumberForm[Pi//N,j],{j,1,10}] Out[1]= {"3.","3.1","3.14","3.142","3.1416","3.14159","3.141593","3.1415927", "3.14159265","3.141592654"} Tomas Garza Mexico City Sistrall [mailto:silvano.stralla at tin.it] wrote: > I've a question about the function N in Mathematica 4. I haven't found > information about this problem. > > The question is: why if I use N[Pi,30] I'll have a number of 30 decimal > digits, but with N[Pi,10] or N[Pi,3] I'll get a number of 6 digits? > > The right number of digits is given only if I use a precision bigger than > the precision of the machine. But if I want a number of 3 decimal digits?