libs/lua/lmathlib.cpp

   1 /*
   2 ** $Id: lmathlib.c,v 1.67 2005/08/26 17:36:32 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 (3.14159265358979323846)
  22 #define RADIANS_PER_DEGREE (PI/180.0)
  23
  24
  25
  26 static int math_abs (lua_State *L) {
  27   lua_pushnumber(L, fabs(luaL_checknumber(L, 1)));
  28   return 1;
  29 }
  30
  31 static int math_sin (lua_State *L) {
  32   lua_pushnumber(L, sin(luaL_checknumber(L, 1)));
  33   return 1;
  34 }
  35
  36 static int math_sinh (lua_State *L) {
  37   lua_pushnumber(L, sinh(luaL_checknumber(L, 1)));
  38   return 1;
  39 }
  40
  41 static int math_cos (lua_State *L) {
  42   lua_pushnumber(L, cos(luaL_checknumber(L, 1)));
  43   return 1;
  44 }
  45
  46 static int math_cosh (lua_State *L) {
  47   lua_pushnumber(L, cosh(luaL_checknumber(L, 1)));
  48   return 1;
  49 }
  50
  51 static int math_tan (lua_State *L) {
  52   lua_pushnumber(L, tan(luaL_checknumber(L, 1)));
  53   return 1;
  54 }
  55
  56 static int math_tanh (lua_State *L) {
  57   lua_pushnumber(L, tanh(luaL_checknumber(L, 1)));
  58   return 1;
  59 }
  60
  61 static int math_asin (lua_State *L) {
  62   lua_pushnumber(L, asin(luaL_checknumber(L, 1)));
  63   return 1;
  64 }
  65
  66 static int math_acos (lua_State *L) {
  67   lua_pushnumber(L, acos(luaL_checknumber(L, 1)));
  68   return 1;
  69 }
  70
  71 static int math_atan (lua_State *L) {
  72   lua_pushnumber(L, atan(luaL_checknumber(L, 1)));
  73   return 1;
  74 }
  75
  76 static int math_atan2 (lua_State *L) {
  77   lua_pushnumber(L, atan2(luaL_checknumber(L, 1), luaL_checknumber(L, 2)));
  78   return 1;
  79 }
  80
  81 static int math_ceil (lua_State *L) {
  82   lua_pushnumber(L, ceil(luaL_checknumber(L, 1)));
  83   return 1;
  84 }
  85
  86 static int math_floor (lua_State *L) {
  87   lua_pushnumber(L, floor(luaL_checknumber(L, 1)));
  88   return 1;
  89 }
  90
  91 static int math_fmod (lua_State *L) {
  92   lua_pushnumber(L, fmod(luaL_checknumber(L, 1), luaL_checknumber(L, 2)));
  93   return 1;
  94 }
  95
  96 static int math_modf (lua_State *L) {
  97   double ip;
  98   double fp = modf(luaL_checknumber(L, 1), &ip);
  99   lua_pushnumber(L, ip);
 100   lua_pushnumber(L, fp);
 101   return 2;
 102 }
 103
 104 static int math_sqrt (lua_State *L) {
 105   lua_pushnumber(L, sqrt(luaL_checknumber(L, 1)));
 106   return 1;
 107 }
 108
 109 static int math_pow (lua_State *L) {
 110   lua_pushnumber(L, pow(luaL_checknumber(L, 1), luaL_checknumber(L, 2)));
 111   return 1;
 112 }
 113
 114 static int math_log (lua_State *L) {
 115   lua_pushnumber(L, log(luaL_checknumber(L, 1)));
 116   return 1;
 117 }
 118
 119 static int math_log10 (lua_State *L) {
 120   lua_pushnumber(L, log10(luaL_checknumber(L, 1)));
 121   return 1;
 122 }
 123
 124 static int math_exp (lua_State *L) {
 125   lua_pushnumber(L, exp(luaL_checknumber(L, 1)));
 126   return 1;
 127 }
 128
 129 static int math_deg (lua_State *L) {
 130   lua_pushnumber(L, luaL_checknumber(L, 1)/RADIANS_PER_DEGREE);
 131   return 1;
 132 }
 133
 134 static int math_rad (lua_State *L) {
 135   lua_pushnumber(L, luaL_checknumber(L, 1)*RADIANS_PER_DEGREE);
 136   return 1;
 137 }
 138
 139 static int math_frexp (lua_State *L) {
 140   int e;
 141   lua_pushnumber(L, frexp(luaL_checknumber(L, 1), &e));
 142   lua_pushinteger(L, e);
 143   return 2;
 144 }
 145
 146 static int math_ldexp (lua_State *L) {
 147   lua_pushnumber(L, ldexp(luaL_checknumber(L, 1), luaL_checkint(L, 2)));
 148   return 1;
 149 }
 150
 151
 152
 153 static int math_min (lua_State *L) {
 154   int n = lua_gettop(L);  /* number of arguments */
 155   lua_Number dmin = luaL_checknumber(L, 1);
 156   int i;
 157   for (i=2; i<=n; i++) {
 158     lua_Number d = luaL_checknumber(L, i);
 159     if (d < dmin)
 160       dmin = d;
 161   }
 162   lua_pushnumber(L, dmin);
 163   return 1;
 164 }
 165
 166
 167 static int math_max (lua_State *L) {
 168   int n = lua_gettop(L);  /* number of arguments */
 169   lua_Number dmax = luaL_checknumber(L, 1);
 170   int i;
 171   for (i=2; i<=n; i++) {
 172     lua_Number d = luaL_checknumber(L, i);
 173     if (d > dmax)
 174       dmax = d;
 175   }
 176   lua_pushnumber(L, dmax);
 177   return 1;
 178 }
 179
 180
 181 static int math_random (lua_State *L) {
 182   /* the `%' avoids the (rare) case of r==1, and is needed also because on
 183      some systems (SunOS!) `rand()' may return a value larger than RAND_MAX */
 184   lua_Number r = (lua_Number)(rand()%RAND_MAX) / (lua_Number)RAND_MAX;
 185   switch (lua_gettop(L)) {  /* check number of arguments */
 186     case 0: {  /* no arguments */
 187       lua_pushnumber(L, r);  /* Number between 0 and 1 */
 188       break;
 189     }
 190     case 1: {  /* only upper limit */
 191       int u = luaL_checkint(L, 1);
 192       luaL_argcheck(L, 1<=u, 1, "interval is empty");
 193       lua_pushnumber(L, floor(r*u)+1);  /* int between 1 and `u' */
 194       break;
 195     }
 196     case 2: {  /* lower and upper limits */
 197       int l = luaL_checkint(L, 1);
 198       int u = luaL_checkint(L, 2);
 199       luaL_argcheck(L, l<=u, 2, "interval is empty");
 200       lua_pushnumber(L, floor(r*(u-l+1))+l);  /* int between `l' and `u' */
 201       break;
 202     }
 203     default: return luaL_error(L, "wrong number of arguments");
 204   }
 205   return 1;
 206 }
 207
 208
 209 static int math_randomseed (lua_State *L) {
 210   srand(luaL_checkint(L, 1));
 211   return 0;
 212 }
 213
 214
 215 static const luaL_Reg mathlib[] = {
 216   {"abs",   math_abs},
 217   {"acos",  math_acos},
 218   {"asin",  math_asin},
 219   {"atan2", math_atan2},
 220   {"atan",  math_atan},
 221   {"ceil",  math_ceil},
 222   {"cosh",   math_cosh},
 223   {"cos",   math_cos},
 224   {"deg",   math_deg},
 225   {"exp",   math_exp},
 226   {"floor", math_floor},
 227   {"fmod",   math_fmod},
 228   {"frexp", math_frexp},
 229   {"ldexp", math_ldexp},
 230   {"log10", math_log10},
 231   {"log",   math_log},
 232   {"max",   math_max},
 233   {"min",   math_min},
 234   {"modf",   math_modf},
 235   {"pow",   math_pow},
 236   {"rad",   math_rad},
 237   {"random",     math_random},
 238   {"randomseed", math_randomseed},
 239   {"sinh",   math_sinh},
 240   {"sin",   math_sin},
 241   {"sqrt",  math_sqrt},
 242   {"tanh",   math_tanh},
 243   {"tan",   math_tan},
 244   {NULL, NULL}
 245 };
 246
 247
 248 /*
 249 ** Open math library
 250 */
 251 LUALIB_API int luaopen_math (lua_State *L) {
 252   luaL_register(L, LUA_MATHLIBNAME, mathlib);
 253   lua_pushnumber(L, PI);
 254   lua_setfield(L, -2, "pi");
 255   lua_pushnumber(L, HUGE_VAL);
 256   lua_setfield(L, -2, "huge");
 257 #if defined(LUA_COMPAT_MOD)
 258   lua_getfield(L, -1, "fmod");
 259   lua_setfield(L, -2, "mod");
 260 #endif
 261   return 1;
 262 }
 263