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Re: Null's not null?

  • To: mathgroup at smc.vnet.net
  • Subject: [mg69402] Re: [mg69393] Null's not null?
  • From: Murray Eisenberg <murray at math.umass.edu>
  • Date: Mon, 11 Sep 2006 05:38:37 -0400 (EDT)
  • Organization: Mathematics & Statistics, Univ. of Mass./Amherst
  • References: <200609101120.HAA11248@smc.vnet.net>
  • Reply-to: murray at math.umass.edu

If I were to be picky, I could way that the behavior of Null in a Table 
and the documentation you cite are NOT inconsistent.  The docs say that 
no output is printed when Null appears "as an output expression" and not 
"in an output expression".

AES wrote:
> Putting Null into one or more slots in a Table and printing the Table 
> shows "Null" (without quotes) at the corresponding positions, as also 
> does ToString[Null].  I don't think that's what the Help message says:
> 
>       "Null is a symbol used to indicate the absence of an 
>        expression or a result. When it appears as an output 
>        expression, no output is printed."
> 
> I can use a string with a couple of empty spaces ("__") to represent an 
> occupied but not empty slot in a Table, but that just looks clumsy to 
> me.  Is there a truly non-printing Null symbol?
> 
> 

-- 
Murray Eisenberg                     murray at math.umass.edu
Mathematics & Statistics Dept.
Lederle Graduate Research Tower      phone 413 549-1020 (H)
University of Massachusetts                413 545-2859 (W)
710 North Pleasant Street            fax   413 545-1801
Amherst, MA 01003-9305


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