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- To: eigen@xxxxxxxxxxxxxxxxxxx
- Subject: Re: [eigen] SSE square root
- From: Rohit Garg <rpg.314@xxxxxxxxx>
- Date: Fri, 27 Mar 2009 16:08:54 +0530
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On Fri, Mar 27, 2009 at 3:58 PM, Gael Guennebaud
<gael.guennebaud@xxxxxxxxx> wrote:
> On Fri, Mar 27, 2009 at 8:32 AM, Rohit Garg <rpg.314@xxxxxxxxx> wrote:
>> This file has my sse float implementation for square root. The SSE
>> square root instruction has only 12 bits of precision so extra
>
> where did you find sqrtss or sqrtps has only 12 bits of precision ?
This info is from the CUDA classes. The lectures put up there say that
the precision for square root is only 12 bits. Now I need to confirm.
Your idea for a approximate reciprocal square root, a mul, and 1
iteration is a good one. Let me try that.
--
Rohit Garg
http://rpg-314.blogspot.com/
Senior Undergraduate
Department of Physics
Indian Institute of Technology
Bombay