OpenCores
URL https://opencores.org/ocsvn/or1k/or1k/trunk

Subversion Repositories or1k

[/] [or1k/] [trunk/] [newlib-1.10.0/] [newlib/] [libm/] [math/] [w_j0.c] - Blame information for rev 1773

Go to most recent revision | Details | Compare with Previous | View Log

Line No. Rev Author Line
1 1010 ivang
 
2
/* @(#)w_j0.c 5.1 93/09/24 */
3
/*
4
 * ====================================================
5
 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
6
 *
7
 * Developed at SunPro, a Sun Microsystems, Inc. business.
8
 * Permission to use, copy, modify, and distribute this
9
 * software is freely granted, provided that this notice
10
 * is preserved.
11
 * ====================================================
12
 */
13
 
14
/*
15
FUNCTION
16
<<jN>>,<<jNf>>,<<yN>>,<<yNf>>---Bessel functions
17
 
18
INDEX
19
j0
20
INDEX
21
j0f
22
INDEX
23
j1
24
INDEX
25
j1f
26
INDEX
27
jn
28
INDEX
29
jnf
30
INDEX
31
y0
32
INDEX
33
y0f
34
INDEX
35
y1
36
INDEX
37
y1f
38
INDEX
39
yn
40
INDEX
41
ynf
42
 
43
ANSI_SYNOPSIS
44
#include <math.h>
45
double j0(double <[x]>);
46
float j0f(float <[x]>);
47
double j1(double <[x]>);
48
float j1f(float <[x]>);
49
double jn(int <[n]>, double <[x]>);
50
float jnf(int <[n]>, float <[x]>);
51
double y0(double <[x]>);
52
float y0f(float <[x]>);
53
double y1(double <[x]>);
54
float y1f(float <[x]>);
55
double yn(int <[n]>, double <[x]>);
56
float ynf(int <[n]>, float <[x]>);
57
 
58
TRAD_SYNOPSIS
59
#include <math.h>
60
 
61
double j0(<[x]>)
62
double <[x]>;
63
float j0f(<[x]>)
64
float <[x]>;
65
double j1(<[x]>)
66
double <[x]>;
67
float j1f(<[x]>)
68
float <[x]>;
69
double jn(<[n]>, <[x]>)
70
int <[n]>;
71
double <[x]>;
72
float jnf(<[n]>, <[x]>)
73
int <[n]>;
74
float <[x]>;
75
 
76
double y0(<[x]>)
77
double <[x]>;
78
float y0f(<[x]>)
79
float <[x]>;
80
double y1(<[x]>)
81
double <[x]>;
82
float y1f(<[x]>)
83
float <[x]>;
84
double yn(<[n]>, <[x]>)
85
int <[n]>;
86
double <[x]>;
87
float ynf(<[n]>, <[x]>)
88
int <[n]>;
89
float <[x]>;
90
 
91
DESCRIPTION
92
The Bessel functions are a family of functions that solve the
93
differential equation
94
@ifinfo
95
.  2               2    2
96
. x  y'' + xy' + (x  - p )y  = 0
97
@end ifinfo
98
@tex
99
$$x^2{d^2y\over dx^2} + x{dy\over dx} + (x^2-p^2)y = 0$$
100
@end tex
101
These functions have many applications in engineering and physics.
102
 
103
<<jn>> calculates the Bessel function of the first kind of order
104
<[n]>.  <<j0>> and <<j1>> are special cases for order 0 and order
105
1 respectively.
106
 
107
Similarly, <<yn>> calculates the Bessel function of the second kind of
108
order <[n]>, and <<y0>> and <<y1>> are special cases for order 0 and
109
1.
110
 
111
<<jnf>>, <<j0f>>, <<j1f>>, <<ynf>>, <<y0f>>, and <<y1f>> perform the
112
same calculations, but on <<float>> rather than <<double>> values.
113
 
114
RETURNS
115
The value of each Bessel function at <[x]> is returned.
116
 
117
PORTABILITY
118
None of the Bessel functions are in ANSI C.
119
*/
120
 
121
/*
122
 * wrapper j0(double x), y0(double x)
123
 */
124
 
125
#include "fdlibm.h"
126
#include <errno.h>
127
 
128
#ifndef _DOUBLE_IS_32BITS
129
 
130
#ifdef __STDC__
131
        double j0(double x)             /* wrapper j0 */
132
#else
133
        double j0(x)                    /* wrapper j0 */
134
        double x;
135
#endif
136
{
137
#ifdef _IEEE_LIBM
138
        return __ieee754_j0(x);
139
#else
140
        struct exception exc;
141
        double z = __ieee754_j0(x);
142
        if(_LIB_VERSION == _IEEE_ || isnan(x)) return z;
143
        if(fabs(x)>X_TLOSS) {
144
            /* j0(|x|>X_TLOSS) */
145
            exc.type = TLOSS;
146
            exc.name = "j0";
147
            exc.err = 0;
148
            exc.arg1 = exc.arg2 = x;
149
            exc.retval = 0.0;
150
            if (_LIB_VERSION == _POSIX_)
151
               errno = ERANGE;
152
            else if (!matherr(&exc)) {
153
               errno = ERANGE;
154
            }
155
            if (exc.err != 0)
156
               errno = exc.err;
157
            return exc.retval;
158
        } else
159
            return z;
160
#endif
161
}
162
 
163
#ifdef __STDC__
164
        double y0(double x)             /* wrapper y0 */
165
#else
166
        double y0(x)                    /* wrapper y0 */
167
        double x;
168
#endif
169
{
170
#ifdef _IEEE_LIBM
171
        return __ieee754_y0(x);
172
#else
173
        double z;
174
        struct exception exc;
175
        z = __ieee754_y0(x);
176
        if(_LIB_VERSION == _IEEE_ || isnan(x) ) return z;
177
        if(x <= 0.0){
178
#ifndef HUGE_VAL 
179
#define HUGE_VAL inf
180
            double inf = 0.0;
181
 
182
            SET_HIGH_WORD(inf,0x7ff00000);      /* set inf to infinite */
183
#endif
184
            /* y0(0) = -inf or y0(x<0) = NaN */
185
            exc.type = DOMAIN;  /* should be SING for IEEE y0(0) */
186
            exc.name = "y0";
187
            exc.err = 0;
188
            exc.arg1 = exc.arg2 = x;
189
            if (_LIB_VERSION == _SVID_)
190
               exc.retval = -HUGE;
191
            else
192
               exc.retval = -HUGE_VAL;
193
            if (_LIB_VERSION == _POSIX_)
194
               errno = EDOM;
195
            else if (!matherr(&exc)) {
196
               errno = EDOM;
197
            }
198
            if (exc.err != 0)
199
               errno = exc.err;
200
            return exc.retval;
201
        }
202
        if(x>X_TLOSS) {
203
            /* y0(x>X_TLOSS) */
204
            exc.type = TLOSS;
205
            exc.name = "y0";
206
            exc.err = 0;
207
            exc.arg1 = exc.arg2 = x;
208
            exc.retval = 0.0;
209
            if (_LIB_VERSION == _POSIX_)
210
               errno = ERANGE;
211
            else if (!matherr(&exc)) {
212
               errno = ERANGE;
213
            }
214
            if (exc.err != 0)
215
               errno = exc.err;
216
            return exc.retval;
217
        } else
218
            return z;
219
#endif
220
}
221
 
222
#endif /* defined(_DOUBLE_IS_32BITS) */
223
 
224
 
225
 
226
 
227
 
228
 
229
 

powered by: WebSVN 2.1.0

© copyright 1999-2024 OpenCores.org, equivalent to Oliscience, all rights reserved. OpenCores®, registered trademark.