/*** $Id: lmathlib.c,v 1.81 2012/05/18 17:47:53 roberto Exp $** Standard mathematical library** See Copyright Notice in lua.h*/  #include <stdlib.h>#include <math.h> #define lmathlib_c#define LUA_LIB #include "lua.h" #include "lauxlib.h"#include "lualib.h"  /* macro 'l_tg' allows the addition of an 'l' or 'f' to all math operations */#if !defined(l_tg)#define l_tg(x)		(x)#endif  #undef PI#define PI (l_tg(3.1415926535897932384626433832795))#define RADIANS_PER_DEGREE (PI/180.0)   static int math_abs (lua_State *L) {  lua_pushnumber(L, l_tg(fabs)(luaL_checknumber(L, 1)));  return 1;} static int math_sin (lua_State *L) {  lua_pushnumber(L, l_tg(sin)(luaL_checknumber(L, 1)));  return 1;} static int math_sinh (lua_State *L) {  lua_pushnumber(L, l_tg(sinh)(luaL_checknumber(L, 1)));  return 1;} static int math_cos (lua_State *L) {  lua_pushnumber(L, l_tg(cos)(luaL_checknumber(L, 1)));  return 1;} static int math_cosh (lua_State *L) {  lua_pushnumber(L, l_tg(cosh)(luaL_checknumber(L, 1)));  return 1;} static int math_tan (lua_State *L) {  lua_pushnumber(L, l_tg(tan)(luaL_checknumber(L, 1)));  return 1;} static int math_tanh (lua_State *L) {  lua_pushnumber(L, l_tg(tanh)(luaL_checknumber(L, 1)));  return 1;} static int math_asin (lua_State *L) {  lua_pushnumber(L, l_tg(asin)(luaL_checknumber(L, 1)));  return 1;} static int math_acos (lua_State *L) {  lua_pushnumber(L, l_tg(acos)(luaL_checknumber(L, 1)));  return 1;} static int math_atan (lua_State *L) {  lua_pushnumber(L, l_tg(atan)(luaL_checknumber(L, 1)));  return 1;} static int math_atan2 (lua_State *L) {  lua_pushnumber(L, l_tg(atan2)(luaL_checknumber(L, 1),                                luaL_checknumber(L, 2)));  return 1;} static int math_ceil (lua_State *L) {  lua_pushnumber(L, l_tg(ceil)(luaL_checknumber(L, 1)));  return 1;} static int math_floor (lua_State *L) {  lua_pushnumber(L, l_tg(floor)(luaL_checknumber(L, 1)));  return 1;} static int math_fmod (lua_State *L) {  lua_pushnumber(L, l_tg(fmod)(luaL_checknumber(L, 1),                               luaL_checknumber(L, 2)));  return 1;} static int math_modf (lua_State *L) {  lua_Number ip;  lua_Number fp = l_tg(modf)(luaL_checknumber(L, 1), &ip);  lua_pushnumber(L, ip);  lua_pushnumber(L, fp);  return 2;} static int math_sqrt (lua_State *L) {  lua_pushnumber(L, l_tg(sqrt)(luaL_checknumber(L, 1)));  return 1;} static int math_pow (lua_State *L) {  lua_pushnumber(L, l_tg(pow)(luaL_checknumber(L, 1),                              luaL_checknumber(L, 2)));  return 1;} static int math_log (lua_State *L) {  lua_Number x = luaL_checknumber(L, 1);  lua_Number res;  if (lua_isnoneornil(L, 2))    res = l_tg(log)(x);  else {    lua_Number base = luaL_checknumber(L, 2);    if (base == 10.0) res = l_tg(log10)(x);    else res = l_tg(log)(x)/l_tg(log)(base);  }  lua_pushnumber(L, res);  return 1;} #if defined(LUA_COMPAT_LOG10)static int math_log10 (lua_State *L) {  lua_pushnumber(L, l_tg(log10)(luaL_checknumber(L, 1)));  return 1;}#endif static int math_exp (lua_State *L) {  lua_pushnumber(L, l_tg(exp)(luaL_checknumber(L, 1)));  return 1;} static int math_deg (lua_State *L) {  lua_pushnumber(L, luaL_checknumber(L, 1)/RADIANS_PER_DEGREE);  return 1;} static int math_rad (lua_State *L) {  lua_pushnumber(L, luaL_checknumber(L, 1)*RADIANS_PER_DEGREE);  return 1;} static int math_frexp (lua_State *L) {  int e;  lua_pushnumber(L, l_tg(frexp)(luaL_checknumber(L, 1), &e));  lua_pushinteger(L, e);  return 2;} static int math_ldexp (lua_State *L) {  lua_pushnumber(L, l_tg(ldexp)(luaL_checknumber(L, 1),                                luaL_checkint(L, 2)));  return 1;}   static int math_min (lua_State *L) {  int n = lua_gettop(L);  /* number of arguments */  lua_Number dmin = luaL_checknumber(L, 1);  int i;  for (i=2; i<=n; i++) {    lua_Number d = luaL_checknumber(L, i);    if (d < dmin)      dmin = d;  }  lua_pushnumber(L, dmin);  return 1;}  static int math_max (lua_State *L) {  int n = lua_gettop(L);  /* number of arguments */  lua_Number dmax = luaL_checknumber(L, 1);  int i;  for (i=2; i<=n; i++) {    lua_Number d = luaL_checknumber(L, i);    if (d > dmax)      dmax = d;  }  lua_pushnumber(L, dmax);  return 1;}  static int math_random (lua_State *L) {  /* the `%' avoids the (rare) case of r==1, and is needed also because on     some systems (SunOS!) `rand()' may return a value larger than RAND_MAX */  lua_Number r = (lua_Number)(rand()%RAND_MAX) / (lua_Number)RAND_MAX;  switch (lua_gettop(L)) {  /* check number of arguments */    case 0: {  /* no arguments */      lua_pushnumber(L, r);  /* Number between 0 and 1 */      break;    }    case 1: {  /* only upper limit */      lua_Number u = luaL_checknumber(L, 1);      luaL_argcheck(L, 1.0 <= u, 1, "interval is empty");      lua_pushnumber(L, l_tg(floor)(r*u) + 1.0);  /* int in [1, u] */      break;    }    case 2: {  /* lower and upper limits */      lua_Number l = luaL_checknumber(L, 1);      lua_Number u = luaL_checknumber(L, 2);      luaL_argcheck(L, l <= u, 2, "interval is empty");      lua_pushnumber(L, l_tg(floor)(r*(u-l+1)) + l);  /* int in [l, u] */      break;    }    default: return luaL_error(L, "wrong number of arguments");  }  return 1;}  static int math_randomseed (lua_State *L) {  srand(luaL_checkunsigned(L, 1));  (void)rand(); /* discard first value to avoid undesirable correlations */  return 0;}  static const luaL_Reg mathlib[] = {  {"abs",   math_abs},  {"acos",  math_acos},  {"asin",  math_asin},  {"atan2", math_atan2},  {"atan",  math_atan},  {"ceil",  math_ceil},  {"cosh",   math_cosh},  {"cos",   math_cos},  {"deg",   math_deg},  {"exp",   math_exp},  {"floor", math_floor},  {"fmod",   math_fmod},  {"frexp", math_frexp},  {"ldexp", math_ldexp},#if defined(LUA_COMPAT_LOG10)  {"log10", math_log10},#endif  {"log",   math_log},  {"max",   math_max},  {"min",   math_min},  {"modf",   math_modf},  {"pow",   math_pow},  {"rad",   math_rad},  {"random",     math_random},  {"randomseed", math_randomseed},  {"sinh",   math_sinh},  {"sin",   math_sin},  {"sqrt",  math_sqrt},  {"tanh",   math_tanh},  {"tan",   math_tan},  {NULL, NULL}};  /*** Open math library*/LUAMOD_API int luaopen_math (lua_State *L) {  luaL_newlib(L, mathlib);  lua_pushnumber(L, PI);  lua_setfield(L, -2, "pi");  lua_pushnumber(L, HUGE_VAL);  lua_setfield(L, -2, "huge");  return 1;}