Date: May 17, 2013 4:34 AM
Author: Murray Eisenberg
Subject: Re: Work on Basic Mathematica Stephen!

If I understand this proposal aa), then I completely disagree. It is *essential* to have the ability to use a function Chop that, e.g., does the following:

Chop[4. + 10.^-16 I]
4.

The reason is that even when one starts with strictly real functions, it is often the case that Mathematica uses complex-function methods and, due to roundoff, returns results with some pure imaginary "fuzz".

On May 16, 2013, at 3:28 AM, Peter Klamser <klamser@googlemail.com> wrote:

> . .. A) First proposal: Identify useless or false constructions in Mathematica
>
> aa) Eliminating Chop[] for complex numbers. Complex numbers are
> oderless and therefore nobody call estimate, weather the distance of 1
> + 10^-google i to the real numbers is small or big. Chop[] is the
> result of Mathematica design, that it presents often complex results, where
> real values are the simpler result and can be reached by
> ComplexExpand[].
> The simplest solution is always the best solution.


---
Murray Eisenberg murray@math.umass.edu
Mathematics & Statistics Dept.
Lederle Graduate Research Tower phone 413 549-1020 (H)
University of Massachusetts 413 545-2838 (W)
710 North Pleasant Street fax 413 545-1801
Amherst, MA 01003-9305