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Date: Mon, 4 Nov 2013 16:55:13 +0000
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Subject: Re: [MATH] Interest in large patches for small cleanup / performance
 changes?
From: sebb <sebbaz@gmail.com>
To: Commons Developers List <dev@commons.apache.org>
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On 2 November 2013 14:52, Sean Owen <srowen@apache.org> wrote:
> In Math, is there any appetite for large patches containing many
> instances of particular micro-optimizations? Examples:
>
> - Replace:
>     a[i][j] =3D a[i][j] + foo;
>   with:
>     a[i][j] +=3D foo;
>   =85 which is faster/leaner in the byte code by a little bit. It might
> make a difference in many nested, tight loops.

Regardless of any speedup, it's safer not to repeat the value.

a[i][j] =3D a[i][j] + foo;
looks a lot like
a[i][j] =3D a[i][i] + foo;
or
a[i][j] =3D a[j][i] + foo;
at first glance, whereas
a[i][j] +=3D foo;
is unambiguous, and much clearer.

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