-- Copyright (C) 1996 Morgan Kaufmann Publishers, Inc
-- This file is part of VESTs (Vhdl tESTs).
-- VESTs is free software; you can redistribute it and/or modify it
-- under the terms of the GNU General Public License as published by the
-- Free Software Foundation; either version 2 of the License, or (at
-- your option) any later version.
-- VESTs is distributed in the hope that it will be useful, but WITHOUT
-- 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
-- along with VESTs; if not, write to the Free Software Foundation,
-- Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
-- ---------------------------------------------------------------------
--
-- $Id: math_real.vhd,v 1.2 2001-10-26 16:29:37 paw Exp $
-- $Revision: 1.2 $
--
-- ---------------------------------------------------------------------
---------------------------------------------------------------
--
-- This source file may be used and distributed without restriction.
-- No declarations or definitions shall be included in this package.
--
-- ****************************************************************
-- * *
-- * W A R N I N G *
-- * *
-- * This DRAFT version IS NOT endorsed or approved by IEEE *
-- * *
-- ****************************************************************
--
-- Title: PACKAGE MATH_REAL
--
-- Library: This package shall be compiled into a library
-- symbolically named IEEE.
--
-- Purpose: VHDL declarations for mathematical package MATH_REAL
-- which contains common real constants, common real
-- functions, and real trascendental functions.
--
-- Author: Based on work by IEEE VHDL Math Package Study Group
--
-- Notes:
-- The package body shall be considered the formal definition of
-- the semantics of this package. Tool developers may choose to implement
-- the package body in the most efficient manner available to them.
--
-- History:
-- Version 0.4 JAT 4/15/93
-------------------------------------------------------------
Library IEEE;
Package MATH_REAL is
--synopsys synthesis_off
constant MATH_E : real := 2.71828_18284_59045_23536;
-- value of e
constant MATH_1_E: real := 0.36787_94411_71442_32160;
-- value of 1/e
constant MATH_PI : real := 3.14159_26535_89793_23846;
-- value of pi
constant MATH_1_PI : real := 0.31830_98861_83790_67154;
-- value of 1/pi
constant MATH_LOG_OF_2: real := 0.69314_71805_59945_30942;
-- natural log of 2
constant MATH_LOG_OF_10: real := 2.30258_50929_94045_68402;
-- natural log of10
constant MATH_LOG2_OF_E: real := 1.44269_50408_88963_4074;
-- log base 2 of e
constant MATH_LOG10_OF_E: real := 0.43429_44819_03251_82765;
-- log base 10 of e
constant MATH_SQRT2: real := 1.41421_35623_73095_04880;
-- sqrt of 2
constant MATH_SQRT1_2: real := 0.70710_67811_86547_52440;
-- sqrt of 1/2
constant MATH_SQRT_PI: real := 1.77245_38509_05516_02730;
-- sqrt of pi
constant MATH_DEG_TO_RAD: real := 0.01745_32925_19943_29577;
-- conversion factor from degree to radian
constant MATH_RAD_TO_DEG: real := 57.29577_95130_82320_87685;
-- conversion factor from radian to degree
--
-- attribute for functions whose implementation is foreign (C native)
--
-- attribute FOREIGN: string; -- predefined attribute in VHDL-1992
--
function SIGN (X: real ) return real;
-- returns 1.0 if X > 0.0; 0.0 if X == 0.0; -1.0 if X < 0.0
function CEIL (X : real ) return real;
-- returns smallest integer value (as real) not less than X
function FLOOR (X : real ) return real;
-- returns largest integer value (as real) not greater than X
function ROUND (X : real ) return real;
-- returns FLOOR(X + 0.5) if X > 0.0;
-- return CEIL(X - 0.5) if X < 0.0
function FMAX (X, Y : real ) return real;
-- returns the algebraically larger of X and Y
function FMIN (X, Y : real ) return real;
-- returns the algebraically smaller of X and Y
function SRAND (seed: in integer ) return integer;
-- attribute FOREIGN of SRAND: function is "C_NATIVE";
-- for VHDL-1992 standard
--
-- sets value of seed for sequence of pseudo-random numbers.
-- returns the value of the seed.
-- It uses the native C function srand().
function RAND return integer;
-- attribute FOREIGN of RAND: function is "C_NATIVE";
-- for VHDL-1992 standard
--
-- returns an integer pseudo-random number with uniform distribution.
-- It uses the native C function rand().
-- Seed for the sequence is initialized with the
-- SRAND() function and value of the seed is changed every
-- time SRAND() is called, but it is not visible.
-- The range of generated values is platform dependent.
function GET_RAND_MAX return integer;
-- attribute FOREIGN of GET_RAND_MAX: function is "C_NATIVE";
-- for VHDL-1992 standard
--
-- returns the upper bound of the range of the
-- pseudo-random numbers generated by RAND().
-- The support for this function is platform dependent.
-- It may not be available in some platforms.
-- Note: the value of (RAND() / GET_RAND_MAX()) is a
-- pseudo-random number distributed between 0 & 1.
function SQRT (X : real ) return real;
-- returns square root of X; X >= 0.0
function CBRT (X : real ) return real;
-- returns cube root of X
function "**" (X : integer; Y : real) return real;
-- returns Y power of X ==> X**Y;
-- error if X = 0 and Y <= 0.0
-- error if X < 0 and Y does not have an integral value
function "**" (X : real; Y : real) return real;
-- returns Y power of X ==> X**Y;
-- error if X = 0.0 and Y <= 0.0
-- error if X < 0.0 and Y does not have an integral value
function EXP (X : real ) return real;
-- returns e**X; where e = MATH_E
function LOG (X : real ) return real;
-- returns natural logarithm of X; X > 0
function LOG (BASE: positive; X : real) return real;
-- returns logarithm base BASE of X; X > 0
function SIN (X : real ) return real;
-- returns sin X; X in radians
function COS ( X : real ) return real;
-- returns cos X; X in radians
function TAN (X : real ) return real;
-- returns tan X; X in radians
-- X /= ((2k+1) * PI/2), where k is an integer
function ASIN (X : real ) return real;
-- returns -PI/2 < asin X < PI/2; | X | <= 1.0
function ACOS (X : real ) return real;
-- returns 0 < acos X < PI; | X | <= 1.0
function ATAN (X : real) return real;
-- returns -PI/2 < atan X < PI/2
function ATAN2 (X : real; Y : real) return real;
-- returns atan (X/Y); -PI < atan2(X,Y) < PI; Y /= 0.0
function SINH (X : real) return real;
-- hyperbolic sine; returns (e**X - e**(-X))/2
function COSH (X : real) return real;
-- hyperbolic cosine; returns (e**X + e**(-X))/2
function TANH (X : real) return real;
-- hyperbolic tangent; -- returns (e**X - e**(-X))/(e**X + e**(-X))
function ASINH (X : real) return real;
-- returns ln( X + sqrt( X**2 + 1))
function ACOSH (X : real) return real;
-- returns ln( X + sqrt( X**2 - 1)); X >= 1.0
function ATANH (X : real) return real;
-- returns (ln( (1 + X)/(1 - X)))/2 ; | X | < 1.0
--synopsys synthesis_on
end MATH_REAL;