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Subject: Re: [boost] Geometry and spatial indexes, my opinion
From: Michael Marcin (mike.marcin_at_[hidden])
Date: 2008-10-13 12:12:20

Mathias Gaunard wrote:
> Brandon Kohn wote:
>> If so, how does direct iteration compare with index
>> operator accesses? I've noticed in my own tests on measuring
>> std::vector accesses that iteration is significantly faster than
>> operator [ ] when you are iterating over the container (presumably due
>> to bounds checking).
> operator[] doesn't do bounds checking, unless you have the debug/secure
> mode of your standard library enabled (which is on by default on MSVC).
> While access by index is theoretically slower than pointer increments,
> I'm pretty sure any compiler optimizes the former to the latter.

At least with MSVC9 they aren't exactly equivalent.

Michael Marcin

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