Re: Precision of calculations

*To*: mathgroup at smc.vnet.net*Subject*: [mg109462] Re: Precision of calculations*From*: Bill Rowe <readnews at sbcglobal.net>*Date*: Wed, 28 Apr 2010 01:59:23 -0400 (EDT)

On 4/27/10 at 4:04 AM, lambaugh at gmail.com (Jim Lambaugh) wrote: >When I write numbers in my code, I do it as (e.g.) >1.0 1000.0 Pi //N etc... >Is it correct to say that my calculations are done with machine- >precision, i.e. with rougly 16 digit precision? Yes. But note, you do not explicitly need to convert exact numbers to machine numbers using N in most cases. For example 1000. Pi computes a machine precision number without explicitly using N. The default for Mathematica is to use machine precision if any portion of an expression is in machine precision and the precision of other portions is not explicitly given.