# File : s-powtab.ads

*------------------------------------------------------------------------------*
*-- --*
*-- GNAT COMPILER COMPONENTS --*
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*------------------------------------------------------------------------------*
*-- This package provides a powers of ten table used for real conversions*
**package** System.Powten_Table **is**
**pragma** Pure;
Maxpow : **constant** := 22;
*-- The number of entries in this table is chosen to include powers of ten*
*-- that are exactly representable with long_long_float. Assuming that on*
*-- all targets we have 53 bits of mantissa for the type, the upper bound is*
*-- given by 53/(log 5). If the scaling factor for a string is greater than*
*-- Maxpow, it can be obtained by several multiplications, which is less*
*-- efficient than with a bigger table, but avoids anomalies at end points.*
Powten : **constant** **array** (0 .. Maxpow) **of** Long_Long_Float :=
(00 => 1.0E+00,
01 => 1.0E+01,
02 => 1.0E+02,
03 => 1.0E+03,
04 => 1.0E+04,
05 => 1.0E+05,
06 => 1.0E+06,
07 => 1.0E+07,
08 => 1.0E+08,
09 => 1.0E+09,
10 => 1.0E+10,
11 => 1.0E+11,
12 => 1.0E+12,
13 => 1.0E+13,
14 => 1.0E+14,
15 => 1.0E+15,
16 => 1.0E+16,
17 => 1.0E+17,
18 => 1.0E+18,
19 => 1.0E+19,
20 => 1.0E+20,
21 => 1.0E+21,
22 => 1.0E+22);
**end** System.Powten_Table;