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: OX Local Data : CMOexpressions for numbers and : CPU dependent double   Ìܼ¡

Bigfloat32

This subsection describes our format for bigfloat in terms of the int32. This format is identical to the internal format of mpfr on 32 bit CPU's.

Ref: OpenXM/src/mpfr/bfsize/bfsize.c

#define     CMO_BIGFLOAT32          52

The bigfloat32 is an array of int32 numbers of the following format.

int32
prec
, int32
sign
, int32
exp
, int32 a[1], ..., int32 a[k]

p=prec is the precision, s=sign is the sign(1 means positive, -1 (expressed by two's complement) is nevative), E=exp is the exponent, and the data above expresses the number

\begin{displaymath}s (a[k]/B + a[k-1]/B^2 + ... + a[1]/B^k) 2^E. \end{displaymath}

Here, $B=2^{32}$, $k = \lceil p/32 \rceil$.



Nobuki Takayama Heisei 28.8.27.