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From: Peter Boettcher <boettcher@ll.mit.edu>
Newsgroups: comp.soft-sys.matlab
Subject: Re: Computer precision?
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Organization: MIT Lincoln Laboratory
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onofftopic@gmail.com writes:

> Hi,
>
> according to the Matlab Help double computer precision (64-bit) is
> default in Matlab for 32-bit computers. Maybe is this question
> offtopic, but i would like to know why is there no higher precision,
> e.g. 128-bit precision, for 32-bit computers?
>
> What is the limitation for the computer precision?

Modern computer hardware implements 64-bit floating point very
efficiently.  Anything larger than that requires software
implementation.  It is possible to implement 128-bit floating point
using pairs of 64-bit FP values, with software glue, but any approach
like this will be much slower than the hardware-supported 64-bit
computations.

-Peter