------------------------------------------------------------------------------
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------------------------------------------------------------------------------

--  This package provides a powers of ten table used for real conversions

package System.Powten_Table is
pragma Pure (Powten_Table);

   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;
