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Diffstat (limited to 'gcc-4.8.1/gcc/ada/g-rannum.ads')
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1 files changed, 138 insertions, 0 deletions
diff --git a/gcc-4.8.1/gcc/ada/g-rannum.ads b/gcc-4.8.1/gcc/ada/g-rannum.ads new file mode 100644 index 000000000..353e21cd0 --- /dev/null +++ b/gcc-4.8.1/gcc/ada/g-rannum.ads @@ -0,0 +1,138 @@ +------------------------------------------------------------------------------ +-- -- +-- GNAT RUN-TIME COMPONENTS -- +-- -- +-- G N A T . R A N D O M _ N U M B E R S -- +-- -- +-- S p e c -- +-- -- +-- Copyright (C) 2007-2009 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 3, 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. -- +-- -- +-- As a special exception under Section 7 of GPL version 3, you are granted -- +-- additional permissions described in the GCC Runtime Library Exception, -- +-- version 3.1, as published by the Free Software Foundation. -- +-- -- +-- You should have received a copy of the GNU General Public License and -- +-- a copy of the GCC Runtime Library Exception along with this program; -- +-- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see -- +-- <http://www.gnu.org/licenses/>. -- +-- -- +-- GNAT was originally developed by the GNAT team at New York University. -- +-- Extensive contributions were provided by Ada Core Technologies Inc. -- +-- -- +------------------------------------------------------------------------------ + +-- Extended pseudo-random number generation + +-- This package provides a type representing pseudo-random number generators, +-- and subprograms to extract various distributions of numbers from them. It +-- also provides types for representing initialization values and snapshots of +-- internal generator state, which permit reproducible pseudo-random streams. + +-- The generator currently provided by this package has an extremely long +-- period (at least 2**19937-1), and passes the Big Crush test suite, with the +-- exception of the two linear complexity tests. Therefore, it is suitable for +-- simulations, but should not be used as a cryptographic pseudo-random source +-- without additional processing. + +-- The design of this package effects is simplified compared to the design +-- of standard Ada.Numerics packages. There is no separate State type; the +-- Generator type itself suffices for this purpose. The parameter modes on +-- Reset procedures better reflect the effect of these routines. + +with System.Random_Numbers; +with Interfaces; use Interfaces; + +package GNAT.Random_Numbers is + + type Generator is limited private; + subtype Initialization_Vector is + System.Random_Numbers.Initialization_Vector; + + function Random (Gen : Generator) return Float; + function Random (Gen : Generator) return Long_Float; + -- Return pseudo-random numbers uniformly distributed on [0 .. 1) + + function Random (Gen : Generator) return Interfaces.Integer_32; + function Random (Gen : Generator) return Interfaces.Unsigned_32; + function Random (Gen : Generator) return Interfaces.Integer_64; + function Random (Gen : Generator) return Interfaces.Unsigned_64; + function Random (Gen : Generator) return Integer; + function Random (Gen : Generator) return Long_Integer; + -- Return pseudo-random numbers uniformly distributed on T'First .. T'Last + -- for various builtin integer types. + + generic + type Result_Subtype is (<>); + Default_Min : Result_Subtype := Result_Subtype'Val (0); + function Random_Discrete + (Gen : Generator; + Min : Result_Subtype := Default_Min; + Max : Result_Subtype := Result_Subtype'Last) return Result_Subtype; + -- Returns pseudo-random numbers uniformly distributed on Min .. Max + + generic + type Result_Subtype is digits <>; + function Random_Float (Gen : Generator) return Result_Subtype; + -- Returns pseudo-random numbers uniformly distributed on [0 .. 1) + + function Random_Gaussian (Gen : Generator) return Long_Float; + function Random_Gaussian (Gen : Generator) return Float; + -- Returns pseudo-random numbers normally distributed value with mean 0 + -- and standard deviation 1.0. + + procedure Reset (Gen : out Generator); + -- Re-initialize the state of Gen from the time of day + + procedure Reset + (Gen : out Generator; + Initiator : Initialization_Vector); + procedure Reset + (Gen : out Generator; + Initiator : Interfaces.Integer_32); + procedure Reset + (Gen : out Generator; + Initiator : Interfaces.Unsigned_32); + procedure Reset + (Gen : out Generator; + Initiator : Integer); + -- Re-initialize Gen based on the Initiator in various ways. Identical + -- values of Initiator cause identical sequences of values. + + procedure Reset (Gen : out Generator; From_State : Generator); + -- Causes the state of Gen to be identical to that of From_State; Gen + -- and From_State will produce identical sequences of values subsequently. + + procedure Reset (Gen : out Generator; From_Image : String); + function Image (Gen : Generator) return String; + -- The call + -- Reset (Gen2, Image (Gen1)) + -- has the same effect as Reset (Gen2, Gen1); + + Max_Image_Width : constant := + System.Random_Numbers.Max_Image_Width + 2 + 20 + 5; + -- Maximum possible length of result of Image (...) + +private + + type Generator is limited record + Rep : System.Random_Numbers.Generator; + + Have_Gaussian : Boolean; + -- The algorithm used for Random_Gaussian produces deviates in + -- pairs. Have_Gaussian is true iff Random_Gaussian has returned one + -- member of the pair and Next_Gaussian contains the other. + + Next_Gaussian : Long_Float; + -- Next random deviate to be produced by Random_Gaussian, if + -- Have_Gaussian. + end record; + +end GNAT.Random_Numbers; |