MathGroup Archive 1999

[Date Index] [Thread Index] [Author Index]

Search the Archive

RE: Re: Packed Arrays in version 4

  • To: mathgroup at
  • Subject: [mg19132] RE: [mg19082] Re: [mg18963] Packed Arrays in version 4
  • From: "Ersek, Ted R" <ErsekTR at>
  • Date: Thu, 5 Aug 1999 23:58:37 -0400
  • Sender: owner-wri-mathgroup at

John Tanner has been trying to find a way to make it so that when a packed
array is multiplied by a complex number a packed array is returned.  He
wants make sure old notebooks that are somewhat large will take full
advantage of packed arrays without doing lots of manual editing.

John wrote:

It has been suggested to me by e-mail that using (N[I]*array) instead of
(I*array) solves the problem, and indeed I had found that
((I+0.0)*array) also solved the problem.  The real problem is that
multiplying a real array by I is so common in electronics/microwaves!  I
have many, many notebooks with many,many,many occurrences of this and I
do not want to start chasing them all down.  Thus I have a real
motivation for making this work as a redefinition of Times or
\[ImaginaryI].  A global redefinition of Global`I := N[System`I] (see my
reply to Bruno Daniel) is probably extremely risky!


I haven't worked out a solution, but you might 
be able to make a function that would automatically 
perform the necessary manipulation on an existing 
notebook to say change (I) to (I+0.0) in all the right places.

How to perform a search and replace in a file is explained at:

Ted Ersek

  • Prev by Date: How to suppress the beep in version 4?
  • Next by Date: RE: Re: Packed Arrays in version 4
  • Previous by thread: Re: Packed Arrays in version 4
  • Next by thread: RE: Re: Packed Arrays in version 4