Re: MachinePrecision vs. Arbitrary Precision
- To: mathgroup at smc.vnet.net
- Subject: [mg118486] Re: MachinePrecision vs. Arbitrary Precision
- From: Bill Rowe <readnews at sbcglobal.net>
- Date: Fri, 29 Apr 2011 07:34:10 -0400 (EDT)
On 4/28/11 at 6:33 AM, mukasa at gmail.com (Sseziwa Mukasa) wrote: >On Apr 27, 2011, at 5:39 AM, Rafael Dunn wrote: >lthe behavior of N[e] and N[e,p] is different even if p >= MachinePrecision, Not correct as easily demonstrated by: In[1]:= a = RealDigits[N[Pi]]; p = MachinePrecision; b = RealDigits[N[Pi, p]]; a === b Out[4]= True But note if you use $MachinePrecision instead of MachinePrecision, then you do get a different behavior, i.e. In[5]:= a = N[Pi, MachinePrecision] Out[5]= 3.14159 In[6]:= b = N[Pi, $MachinePrecision] Out[6]= 3.141592653589793 But what is being retained is still identical in both cases. In[7]:= a === b Out[7]= True