1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
|
-- 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;
|
