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 
math_abs(lua_State * L)26 static int math_abs (lua_State *L) {
27   lua_pushnumber(L, l_mathop(fabs)(luaL_checknumber(L, 1)));
28   return 1;
29 }
30 
math_sin(lua_State * L)31 static int math_sin (lua_State *L) {
32   lua_pushnumber(L, l_mathop(sin)(luaL_checknumber(L, 1)));
33   return 1;
34 }
35 
math_sinh(lua_State * L)36 static int math_sinh (lua_State *L) {
37   lua_pushnumber(L, l_mathop(sinh)(luaL_checknumber(L, 1)));
38   return 1;
39 }
40 
math_cos(lua_State * L)41 static int math_cos (lua_State *L) {
42   lua_pushnumber(L, l_mathop(cos)(luaL_checknumber(L, 1)));
43   return 1;
44 }
45 
math_cosh(lua_State * L)46 static int math_cosh (lua_State *L) {
47   lua_pushnumber(L, l_mathop(cosh)(luaL_checknumber(L, 1)));
48   return 1;
49 }
50 
math_tan(lua_State * L)51 static int math_tan (lua_State *L) {
52   lua_pushnumber(L, l_mathop(tan)(luaL_checknumber(L, 1)));
53   return 1;
54 }
55 
math_tanh(lua_State * L)56 static int math_tanh (lua_State *L) {
57   lua_pushnumber(L, l_mathop(tanh)(luaL_checknumber(L, 1)));
58   return 1;
59 }
60 
math_asin(lua_State * L)61 static int math_asin (lua_State *L) {
62   lua_pushnumber(L, l_mathop(asin)(luaL_checknumber(L, 1)));
63   return 1;
64 }
65 
math_acos(lua_State * L)66 static int math_acos (lua_State *L) {
67   lua_pushnumber(L, l_mathop(acos)(luaL_checknumber(L, 1)));
68   return 1;
69 }
70 
math_atan(lua_State * L)71 static int math_atan (lua_State *L) {
72   lua_pushnumber(L, l_mathop(atan)(luaL_checknumber(L, 1)));
73   return 1;
74 }
75 
math_atan2(lua_State * L)76 static 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 
math_ceil(lua_State * L)82 static int math_ceil (lua_State *L) {
83   lua_pushnumber(L, l_mathop(ceil)(luaL_checknumber(L, 1)));
84   return 1;
85 }
86 
math_floor(lua_State * L)87 static int math_floor (lua_State *L) {
88   lua_pushnumber(L, l_mathop(floor)(luaL_checknumber(L, 1)));
89   return 1;
90 }
91 
math_fmod(lua_State * L)92 static 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 
math_modf(lua_State * L)98 static 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 
math_sqrt(lua_State * L)106 static int math_sqrt (lua_State *L) {
107   lua_pushnumber(L, l_mathop(sqrt)(luaL_checknumber(L, 1)));
108   return 1;
109 }
110 
math_pow(lua_State * L)111 static 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 
math_log(lua_State * L)118 static 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)
math_log10(lua_State * L)133 static int math_log10 (lua_State *L) {
134   lua_pushnumber(L, l_mathop(log10)(luaL_checknumber(L, 1)));
135   return 1;
136 }
137 #endif
138 
math_exp(lua_State * L)139 static int math_exp (lua_State *L) {
140   lua_pushnumber(L, l_mathop(exp)(luaL_checknumber(L, 1)));
141   return 1;
142 }
143 
math_deg(lua_State * L)144 static int math_deg (lua_State *L) {
145   lua_pushnumber(L, luaL_checknumber(L, 1)/RADIANS_PER_DEGREE);
146   return 1;
147 }
148 
math_rad(lua_State * L)149 static int math_rad (lua_State *L) {
150   lua_pushnumber(L, luaL_checknumber(L, 1)*RADIANS_PER_DEGREE);
151   return 1;
152 }
153 
math_frexp(lua_State * L)154 static 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 
math_ldexp(lua_State * L)161 static 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 
math_min(lua_State * L)170 static 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 
math_max(lua_State * L)184 static 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 
math_random(lua_State * L)198 static 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 
math_randomseed(lua_State * L)226 static 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 
233 static 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 */
luaopen_math(lua_State * L)271 LUAMOD_API int luaopen_math (lua_State *L) {
272   luaL_newlib(L, mathlib);
273   lua_pushnumber(L, PI);
274   lua_setfield(L, -2, "pi");
275   lua_pushnumber(L, HUGE_VAL);
276   lua_setfield(L, -2, "huge");
277   return 1;
278 }
279 
280