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From: Thomas 'PointedEars' Lahn <PointedEars@web.de>
Newsgroups: comp.lang.javascript
Subject: Re: Impact of implicit arrays...
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Date: Wed, 15 Jun 2016 06:55:26 +0200
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Chris M. Thomasson wrote:

> Also, we can do this another way that involves an explicit
> output parameter to the function. Something like:
> _______________________________________
> function ct_complex_mul(c0, c1, out)
                                  ^^^
> {
>      out[0] = c0[0] * c1[0] - c0[1] * c1[1];
>      out[1] = c0[0] * c1[1] + c0[1] * c1[0];
> 
>      return out;
> }
> _______________________________________
> 
> 
> To call it in a loop could look like:
> _______________________________________
> function foo_with_out()
> {
>     var out = [0, 0];
>     var z = [1, 1];
>     var c = [2, 2];
> 
>     for (var i = 0; i < 10; ++i)
>     {
>         out = ct_complex_mul(z, c);
                                   ^^
>         z[0] = out[0];
>         z[1] = out[1];
>     }
> }
> _______________________________________

No, that would be pointless.  In fact, the function SHOULD NOT *return* the 
changed value then.

But this non-idempotent, non-reentrant code is not thread-safe – it is not 
suited for animations.
 
>> Another thought is to switch to polar coordinates
>> instead of Cartesian coordinates as it would simplify
>> multiplication and division at least. With fractal based
>> work this might be more intuitive anyway, yes?
> 
> Right. However, I think that converting Polar into Cartesian
> in order to add/subtract is the simplest route correct?

Yes.  UTSL.


The “From” and “Reply-To” header fields of your postings are borked, see

<http://www.interhack.net/pubs/munging-harmful/>
<http://tools.ietf.org/html/rfc5536#section-3.1.2>
<http://tools.ietf.org/html/rfc5536#section-3.2>

You should also avoid the troll server, aioe.org.

Pseudo-address added to killfile.

F'up2 poster

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