lua51 0.1.6

/*
** $Id: lmathlib.c,v 1.67.1.1 2007/12/27 13:02:25 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"


#undef PI
#define PI (3.14159265358979323846)

#define RADIANS_PER_DEGREE (PI/180.0)



static int math_abs(lua_State *L) {
    lua_pushnumber(L, fabs(luaL_checknumber(L, 1)));
    return 1;
}

static int math_sin(lua_State *L) {
    lua_pushnumber(L, sin(luaL_checknumber(L, 1)));
    return 1;
}

static int math_sinh(lua_State *L) {
    lua_pushnumber(L, sinh(luaL_checknumber(L, 1)));
    return 1;
}

static int math_cos(lua_State *L) {
    lua_pushnumber(L, cos(luaL_checknumber(L, 1)));
    return 1;
}

static int math_cosh(lua_State *L) {
    lua_pushnumber(L, cosh(luaL_checknumber(L, 1)));
    return 1;
}

static int math_tan(lua_State *L) {
    lua_pushnumber(L, tan(luaL_checknumber(L, 1)));
    return 1;
}

static int math_tanh(lua_State *L) {
    lua_pushnumber(L, tanh(luaL_checknumber(L, 1)));
    return 1;
}

static int math_asin(lua_State *L) {
    lua_pushnumber(L, asin(luaL_checknumber(L, 1)));
    return 1;
}

static int math_acos(lua_State *L) {
    lua_pushnumber(L, acos(luaL_checknumber(L, 1)));
    return 1;
}

static int math_atan(lua_State *L) {
    lua_pushnumber(L, atan(luaL_checknumber(L, 1)));
    return 1;
}

static int math_atan2(lua_State *L) {
    lua_pushnumber(L, atan2(luaL_checknumber(L, 1), luaL_checknumber(L, 2)));
    return 1;
}

static int math_ceil(lua_State *L) {
    lua_pushnumber(L, ceil(luaL_checknumber(L, 1)));
    return 1;
}

static int math_floor(lua_State *L) {
    lua_pushnumber(L, floor(luaL_checknumber(L, 1)));
    return 1;
}

static int math_fmod(lua_State *L) {
    lua_pushnumber(L, fmod(luaL_checknumber(L, 1), luaL_checknumber(L, 2)));
    return 1;
}

static int math_modf(lua_State *L) {
    double ip;
    double fp = 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, sqrt(luaL_checknumber(L, 1)));
    return 1;
}

static int math_pow(lua_State *L) {
    lua_pushnumber(L, pow(luaL_checknumber(L, 1), luaL_checknumber(L, 2)));
    return 1;
}

static int math_log(lua_State *L) {
    lua_pushnumber(L, log(luaL_checknumber(L, 1)));
    return 1;
}

static int math_log10(lua_State *L) {
    lua_pushnumber(L, log10(luaL_checknumber(L, 1)));
    return 1;
}

static int math_exp(lua_State *L) {
    lua_pushnumber(L, 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, frexp(luaL_checknumber(L, 1), &e));
    lua_pushinteger(L, e);
    return 2;
}

static int math_ldexp(lua_State *L) {
    lua_pushnumber(L, 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 */
            int u = luaL_checkint(L, 1);
            luaL_argcheck(L, 1 <= u, 1, "interval is empty");
            lua_pushnumber(L, floor(r * u) + 1);  /* int between 1 and `u' */
            break;
        }
        case 2: {  /* lower and upper limits */
            int l = luaL_checkint(L, 1);
            int u = luaL_checkint(L, 2);
            luaL_argcheck(L, l <= u, 2, "interval is empty");
            lua_pushnumber(L, floor(r * (u - l + 1)) + l);  /* int between `l' and `u' */
            break;
        }
        default:
            return luaL_error(L, "wrong number of arguments");
    }
    return 1;
}


static int math_randomseed(lua_State *L) {
    srand(luaL_checkint(L, 1));
    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},
        {"log10",      math_log10},
        {"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
*/
LUALIB_API int luaopen_math(lua_State *L) {
    luaL_register(L, LUA_MATHLIBNAME, mathlib);
    lua_pushnumber(L, PI);
    lua_setfield(L, -2, "pi");
    lua_pushnumber(L, HUGE_VAL);
    lua_setfield(L, -2, "huge");
#if defined(LUA_COMPAT_MOD)
    lua_getfield(L, -1, "fmod");
    lua_setfield(L, -2, "mod");
#endif
    return 1;
}