------------------------------------------------------------------------------ -- -- -- GNAT COMPILER COMPONENTS -- -- -- -- S Y S T E M . P O W T E N _ T A B L E -- -- -- -- S p e c -- -- -- -- Copyright (C) 1992-1999 Free Software Foundation, Inc. -- -- -- -- GNAT is free software; you can redistribute it and/or modify it under -- -- terms of the GNU General Public License as published by the Free Soft- -- -- ware Foundation; either version 2, or (at your option) any later ver- -- -- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License -- -- for more details. You should have received a copy of the GNU General -- -- Public License distributed with GNAT; see file COPYING. If not, write -- -- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, -- -- MA 02111-1307, USA. -- -- -- -- As a special exception, if other files instantiate generics from this -- -- unit, or you link this unit with other files to produce an executable, -- -- this unit does not by itself cause the resulting executable to be -- -- covered by the GNU General Public License. This exception does not -- -- however invalidate any other reasons why the executable file might be -- -- covered by the GNU Public License. -- -- -- -- GNAT was originally developed by the GNAT team at New York University. -- -- Extensive contributions were provided by Ada Core Technologies Inc. -- -- -- ------------------------------------------------------------------------------ -- 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;