1/*
2** $Id: lmathlib.c,v 1.83.1.1 2013/04/12 18:48:47 roberto Exp $
3** Standard mathematical library
4** See Copyright Notice in lua.h
5*/
6
7
8#include <stdlib.h>
9#include <math.h>
10
11#define lmathlib_c
12#define LUA_LIB
13
14#include "lua.h"
15
16#include "lauxlib.h"
17#include "lualib.h"
18
19
20#undef PI
21#define PI	((lua_Number)(3.1415926535897932384626433832795))
22#define RADIANS_PER_DEGREE	((lua_Number)(PI/180.0))
23
24
25
26static int math_abs (lua_State *L) {
27  lua_pushnumber(L, l_mathop(fabs)(luaL_checknumber(L, 1)));
28  return 1;
29}
30
31static int math_sin (lua_State *L) {
32  lua_pushnumber(L, l_mathop(sin)(luaL_checknumber(L, 1)));
33  return 1;
34}
35
36static int math_sinh (lua_State *L) {
37  lua_pushnumber(L, l_mathop(sinh)(luaL_checknumber(L, 1)));
38  return 1;
39}
40
41static int math_cos (lua_State *L) {
42  lua_pushnumber(L, l_mathop(cos)(luaL_checknumber(L, 1)));
43  return 1;
44}
45
46static int math_cosh (lua_State *L) {
47  lua_pushnumber(L, l_mathop(cosh)(luaL_checknumber(L, 1)));
48  return 1;
49}
50
51static int math_tan (lua_State *L) {
52  lua_pushnumber(L, l_mathop(tan)(luaL_checknumber(L, 1)));
53  return 1;
54}
55
56static int math_tanh (lua_State *L) {
57  lua_pushnumber(L, l_mathop(tanh)(luaL_checknumber(L, 1)));
58  return 1;
59}
60
61static int math_asin (lua_State *L) {
62  lua_pushnumber(L, l_mathop(asin)(luaL_checknumber(L, 1)));
63  return 1;
64}
65
66static int math_acos (lua_State *L) {
67  lua_pushnumber(L, l_mathop(acos)(luaL_checknumber(L, 1)));
68  return 1;
69}
70
71static int math_atan (lua_State *L) {
72  lua_pushnumber(L, l_mathop(atan)(luaL_checknumber(L, 1)));
73  return 1;
74}
75
76static int math_atan2 (lua_State *L) {
77  lua_pushnumber(L, l_mathop(atan2)(luaL_checknumber(L, 1),
78                                luaL_checknumber(L, 2)));
79  return 1;
80}
81
82static int math_ceil (lua_State *L) {
83  lua_pushnumber(L, l_mathop(ceil)(luaL_checknumber(L, 1)));
84  return 1;
85}
86
87static int math_floor (lua_State *L) {
88  lua_pushnumber(L, l_mathop(floor)(luaL_checknumber(L, 1)));
89  return 1;
90}
91
92static int math_fmod (lua_State *L) {
93  lua_pushnumber(L, l_mathop(fmod)(luaL_checknumber(L, 1),
94                               luaL_checknumber(L, 2)));
95  return 1;
96}
97
98static int math_modf (lua_State *L) {
99  lua_Number ip;
100  lua_Number fp = l_mathop(modf)(luaL_checknumber(L, 1), &ip);
101  lua_pushnumber(L, ip);
102  lua_pushnumber(L, fp);
103  return 2;
104}
105
106static int math_sqrt (lua_State *L) {
107  lua_pushnumber(L, l_mathop(sqrt)(luaL_checknumber(L, 1)));
108  return 1;
109}
110
111static int math_pow (lua_State *L) {
112  lua_Number x = luaL_checknumber(L, 1);
113  lua_Number y = luaL_checknumber(L, 2);
114  lua_pushnumber(L, l_mathop(pow)(x, y));
115  return 1;
116}
117
118static int math_log (lua_State *L) {
119  lua_Number x = luaL_checknumber(L, 1);
120  lua_Number res;
121  if (lua_isnoneornil(L, 2))
122    res = l_mathop(log)(x);
123  else {
124    lua_Number base = luaL_checknumber(L, 2);
125    if (base == (lua_Number)10.0) res = l_mathop(log10)(x);
126    else res = l_mathop(log)(x)/l_mathop(log)(base);
127  }
128  lua_pushnumber(L, res);
129  return 1;
130}
131
132#if defined(LUA_COMPAT_LOG10)
133static int math_log10 (lua_State *L) {
134  lua_pushnumber(L, l_mathop(log10)(luaL_checknumber(L, 1)));
135  return 1;
136}
137#endif
138
139static int math_exp (lua_State *L) {
140  lua_pushnumber(L, l_mathop(exp)(luaL_checknumber(L, 1)));
141  return 1;
142}
143
144static int math_deg (lua_State *L) {
145  lua_pushnumber(L, luaL_checknumber(L, 1)/RADIANS_PER_DEGREE);
146  return 1;
147}
148
149static int math_rad (lua_State *L) {
150  lua_pushnumber(L, luaL_checknumber(L, 1)*RADIANS_PER_DEGREE);
151  return 1;
152}
153
154static int math_frexp (lua_State *L) {
155  int e;
156  lua_pushnumber(L, l_mathop(frexp)(luaL_checknumber(L, 1), &e));
157  lua_pushinteger(L, e);
158  return 2;
159}
160
161static int math_ldexp (lua_State *L) {
162  lua_Number x = luaL_checknumber(L, 1);
163  int ep = luaL_checkint(L, 2);
164  lua_pushnumber(L, l_mathop(ldexp)(x, ep));
165  return 1;
166}
167
168
169
170static int math_min (lua_State *L) {
171  int n = lua_gettop(L);  /* number of arguments */
172  lua_Number dmin = luaL_checknumber(L, 1);
173  int i;
174  for (i=2; i<=n; i++) {
175    lua_Number d = luaL_checknumber(L, i);
176    if (d < dmin)
177      dmin = d;
178  }
179  lua_pushnumber(L, dmin);
180  return 1;
181}
182
183
184static int math_max (lua_State *L) {
185  int n = lua_gettop(L);  /* number of arguments */
186  lua_Number dmax = luaL_checknumber(L, 1);
187  int i;
188  for (i=2; i<=n; i++) {
189    lua_Number d = luaL_checknumber(L, i);
190    if (d > dmax)
191      dmax = d;
192  }
193  lua_pushnumber(L, dmax);
194  return 1;
195}
196
197
198static int math_random (lua_State *L) {
199  /* the `%' avoids the (rare) case of r==1, and is needed also because on
200     some systems (SunOS!) `rand()' may return a value larger than RAND_MAX */
201  lua_Number r = (lua_Number)(rand()%RAND_MAX) / (lua_Number)RAND_MAX;
202  switch (lua_gettop(L)) {  /* check number of arguments */
203    case 0: {  /* no arguments */
204      lua_pushnumber(L, r);  /* Number between 0 and 1 */
205      break;
206    }
207    case 1: {  /* only upper limit */
208      lua_Number u = luaL_checknumber(L, 1);
209      luaL_argcheck(L, (lua_Number)1.0 <= u, 1, "interval is empty");
210      lua_pushnumber(L, l_mathop(floor)(r*u) + (lua_Number)(1.0));  /* [1, u] */
211      break;
212    }
213    case 2: {  /* lower and upper limits */
214      lua_Number l = luaL_checknumber(L, 1);
215      lua_Number u = luaL_checknumber(L, 2);
216      luaL_argcheck(L, l <= u, 2, "interval is empty");
217      lua_pushnumber(L, l_mathop(floor)(r*(u-l+1)) + l);  /* [l, u] */
218      break;
219    }
220    default: return luaL_error(L, "wrong number of arguments");
221  }
222  return 1;
223}
224
225
226static int math_randomseed (lua_State *L) {
227  srand(luaL_checkunsigned(L, 1));
228  (void)rand(); /* discard first value to avoid undesirable correlations */
229  return 0;
230}
231
232
233static const luaL_Reg mathlib[] = {
234  {"abs",   math_abs},
235  {"acos",  math_acos},
236  {"asin",  math_asin},
237  {"atan2", math_atan2},
238  {"atan",  math_atan},
239  {"ceil",  math_ceil},
240  {"cosh",   math_cosh},
241  {"cos",   math_cos},
242  {"deg",   math_deg},
243  {"exp",   math_exp},
244  {"floor", math_floor},
245  {"fmod",   math_fmod},
246  {"frexp", math_frexp},
247  {"ldexp", math_ldexp},
248#if defined(LUA_COMPAT_LOG10)
249  {"log10", math_log10},
250#endif
251  {"log",   math_log},
252  {"max",   math_max},
253  {"min",   math_min},
254  {"modf",   math_modf},
255  {"pow",   math_pow},
256  {"rad",   math_rad},
257  {"random",     math_random},
258  {"randomseed", math_randomseed},
259  {"sinh",   math_sinh},
260  {"sin",   math_sin},
261  {"sqrt",  math_sqrt},
262  {"tanh",   math_tanh},
263  {"tan",   math_tan},
264  {NULL, NULL}
265};
266
267
268/*
269** Open math library
270*/
271LUAMOD_API int luaopen_math (lua_State *L) {
272  luaL_newlib(L, mathlib);
273  lua_pushnumber(L, PI);
274  lua_setfield(L, -2, "pi");
275#ifndef LUA_NUMBER_INTEGRAL
276  lua_pushnumber(L, HUGE_VAL);
277  lua_setfield(L, -2, "huge");
278#endif
279  return 1;
280}
281
282