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Re: Simple list question

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From	Bill Rowe <readnews@sbcglobal.net>
Newsgroups	comp.soft-sys.math.mathematica
Subject	Re: Simple list question
Date	Tue, 15 Apr 2014 03:02:06 +0000 (UTC)
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On 4/14/14 at 5:28 AM, stevebg@roadrunner.com (Ste[hen Gray) wrote:

>pcin = 2;
>pcex = 3;   (*pcin and pcex can have various small values *)
>
>coin = Table[{10 RandomReal[], 10 RandomReal[]}, {pcin}]
>coex = Table[{3 RandomReal[], 3 RandomReal[]}, {pcex}]
>cobo = Append[coin, coex]
>pcin = 2;
>pcex = 3;   (*pcin and pcex can have various small values *)
>
>coin = Table[{10 RandomReal[], 10 RandomReal[]}, {pcin}]
>coex = Table[{3 RandomReal[], 3 RandomReal[]}, {pcex}]
>cobo = Append[coin, coex]

<snip>

>What I want is a series of x,y coordinates with no extra nesting:

Instead of Append, use Join, i.e.

cobo = Join[coin, coex]

In fact, Append is something to generally avoid using
particularly for large arrays due to the computing resources
used. It will require more memory and is slower. Won't matter
for small arrays like this. But for large arrays, Append is very
much a problem and better replaced with other commands such as Join.

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Re: Simple list question Bill Rowe <readnews@sbcglobal.net> - 2014-04-15 03:02 +0000
  Speed of Join and Append.   Was Re: Simple list question Richard Fateman <fateman@cs.berkeley.edu> - 2014-04-16 07:40 +0000

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