static int cdf_dbeta (lua_State *L) {
/* stack should contain x, a and b */
lua_Number x = luaL_checknumber(L, 1);
lua_Number a = luaL_checknumber(L, 2);
lua_Number b = luaL_checknumber(L, 3);
check_beta(L, 1, x, a, b);
lua_pushnumber(L, (x==0 || x==1) ? 0 :
exp((a-1)*log(x)+(b-1)*log(1-x)-dlnbet(&a, &b)));
return 1;
}
static int cdf_pbeta (lua_State *L) {
/* stack should contain x, a and b */
lua_Number x = luaL_checknumber(L, 1);
lua_Number a = luaL_checknumber(L, 2);
lua_Number b = luaL_checknumber(L, 3);
lua_Number p, q, y, bound;
int which = 1;
int status;
check_beta(L, 1, x, a, b);
y = 1-x;
cdfbet(&which, &p, &q, &x, &y, &a, &b, &status, &bound);
check_status(status, bound);
lua_pushnumber(L, p);
return 1;
}
static int cdf_qbeta (lua_State *L) {
/* stack should contain x, a and b */
lua_Number p = luaL_checknumber(L, 1);
lua_Number a = luaL_checknumber(L, 2);
lua_Number b = luaL_checknumber(L, 3);
lua_Number x;
check_beta(L, 2, p, a, b);
if (p==0 || p==1) x = p;
else {
lua_Number q, y, bound;
int which = 2;
int status;
q = 1-p;
cdfbet(&which, &p, &q, &x, &y, &a, &b, &status, &bound);
check_status(status, bound);
}
lua_pushnumber(L, x);
return 1;
}
inline bool check_dist(const char* function, const RealType& alpha, const RealType& beta, RealType* result, const Policy& pol)
{ // Check both alpha and beta.
return check_alpha(function, alpha, result, pol)
&& check_beta(function, beta, result, pol);
} // bool check_dist