org.luaj.vm2.lib
Class MathLib

java.lang.Object
  org.luaj.vm2.Varargs
      org.luaj.vm2.LuaValue
          org.luaj.vm2.LuaFunction
              org.luaj.vm2.lib.LibFunction
                  org.luaj.vm2.lib.OneArgFunction
                      org.luaj.vm2.lib.MathLib

Direct Known Subclasses:

JseMathLib

public class MathLib
extends OneArgFunction

Subclass of LibFunction which implements the lua standard math library.

It contains only the math library support that is possible on JME. For a more complete implementation based on math functions specific to JSE use JseMathLib. In Particular the following math functions are not implemented by this library:

• acos
• asin
• atan
• cosh
• log
• log10
• sinh
• tanh
• atan2

The implementations of exp() and pow() are constructed by hand for JME, so will be slower and less accurate than when executed on the JSE platform.

Typically, this library is included as part of a call to either JmePlatform#standardGlobals()

To instantiate and use it directly, link it into your globals table via LuaValue.load(LuaValue) using code such as:

 LuaTable _G = new LuaTable();
 LuaThread.setGlobals(_G);
 _G.load(new BaseLib());
 _G.load(new PackageLib());
 _G.load(new MathLib());
 System.out.println( _G.get("math").get("sqrt").call( LuaValue.valueOf(2) ) );
  

Doing so will ensure the library is properly initialized and loaded into the globals table.

This has been implemented to match as closely as possible the behavior in the corresponding library in C.

See Also:

LibFunction, JsePlatform, JmePlatform, JseMathLib, http://www.lua.org/manual/5.1/manual.html#5.6

Field Summary

static MathLib

MATHLIB

Fields inherited from class org.luaj.vm2.lib.LibFunction

name, opcode

Fields inherited from class org.luaj.vm2.LuaFunction

env, s_metatable

Fields inherited from class org.luaj.vm2.LuaValue

ADD, CALL, CONCAT, DIV, EMPTYSTRING, EQ, FALSE, INDEX, LE, LEN, LT, METATABLE, MINUSONE, MOD, MODE, MUL, NEWINDEX, NIL, NILS, NONE, NOVALS, ONE, POW, SUB, TBOOLEAN, TFUNCTION, TINT, TLIGHTUSERDATA, TNIL, TNONE, TNUMBER, TOSTRING, TRUE, TSTRING, TTABLE, TTHREAD, TUSERDATA, TVALUE, TYPE_NAMES, UNM, ZERO

Constructor Summary

MathLib()

Method Summary

LuaValue	call(LuaValue arg) Call this with 1 argument, including metatag processing, and return only the first return value.
static double	dpow_d(double a, double b)
protected static double	dpow_default(double a, double b) Default JME version computes using longhand heuristics.
double	dpow_lib(double a, double b) Hook to override default dpow behavior with faster implementation.
static LuaValue	dpow(double a, double b) compute power using installed math library, or default if there is no math library installed

Methods inherited from class org.luaj.vm2.lib.OneArgFunction

call, call, call, invoke

Methods inherited from class org.luaj.vm2.lib.LibFunction

bind, bind, newupe, newupl, newupn, tojstring

Methods inherited from class org.luaj.vm2.LuaFunction

checkfunction, getfenv, getmetatable, isfunction, optfunction, setfenv, type, typename

Methods inherited from class org.luaj.vm2.LuaValue

add, add, add, and, arg, arg1, argerror, argerror, aritherror, aritherror, arithmt, arithmtwith, assert_, buffer, callmt, checkboolean, checkclosure, checkdouble, checkint, checkinteger, checkjstring, checklong, checkmetatag, checknotnil, checknumber, checknumber, checkstring, checktable, checkthread, checkuserdata, checkuserdata, checkvalidkey, compareerror, compareerror, comparemt, concat, concat, concatmt, concatTo, concatTo, concatTo, div, div, div, divInto, eq_b, eq, eqmtcall, equals, error, get, get, get, getn, gettable, gt_b, gt_b, gt_b, gt, gt, gt, gteq_b, gteq_b, gteq_b, gteq, gteq, gteq, illegal, inext, invoke, invoke, invoke, invoke, invoke, invokemethod, invokemethod, invokemethod, invokemethod, invokemethod, invokemethod, isboolean, isclosure, isint, isinttype, islong, isnil, isnumber, isstring, istable, isthread, isuserdata, isuserdata, isweaknil, len, lenerror, length, listOf, listOf, load, lt_b, lt_b, lt_b, lt, lt, lt, lteq_b, lteq_b, lteq_b, lteq, lteq, lteq, metatag, method, method, method, method, method, method, mod, mod, mod, modFrom, mul, mul, mul, narg, neg, neq_b, neq, next, not, onInvoke, optboolean, optclosure, optdouble, optint, optinteger, optjstring, optlong, optnumber, optstring, opttable, optthread, optuserdata, optuserdata, optvalue, or, pow, pow, pow, powWith, powWith, presize, raweq, raweq, raweq, raweq, raweq, rawget, rawget, rawget, rawset, rawset, rawset, rawset, rawset, rawset, rawset, rawsetlist, set, set, set, set, set, set, set, setmetatable, settable, strcmp, strcmp, strongkey, strongvalue, strvalue, sub, sub, sub, subFrom, subFrom, tableOf, tableOf, tableOf, tableOf, tableOf, tableOf, tailcallOf, testfor_b, toboolean, tobyte, tochar, todouble, tofloat, toint, tolong, tonumber, toshort, tostring, toString, touserdata, touserdata, typerror, unimplemented, userdataOf, userdataOf, valueOf, valueOf, valueOf, valueOf, valueOf, valueOf, varargsOf, varargsOf, varargsOf, varargsOf, varargsOf, varargsOf

Methods inherited from class org.luaj.vm2.Varargs

argcheck, checkboolean, checkclosure, checkdouble, checkfunction, checkint, checkinteger, checkjstring, checklong, checknotnil, checknumber, checkstring, checktable, checkthread, checkuserdata, checkuserdata, checkvalue, eval, isfunction, isnil, isnoneornil, isnumber, isstring, istable, isTailcall, isthread, isuserdata, isvalue, optboolean, optclosure, optdouble, optfunction, optint, optinteger, optjstring, optlong, optnumber, optstring, opttable, optthread, optuserdata, optuserdata, optvalue, subargs, toboolean, tobyte, tochar, todouble, tofloat, toint, tojstring, tolong, toshort, touserdata, touserdata, type

Methods inherited from class java.lang.Object

clone, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

MATHLIB

public static MathLib MATHLIB

Constructor Detail

MathLib

public MathLib()

Method Detail

call

public LuaValue call(LuaValue arg)

Description copied from class: LuaValue

Call this with 1 argument, including metatag processing, and return only the first return value.

If this is a LuaFunction, call it, and return only its first return value, dropping any others. Otherwise, look for the CALL metatag and call that.

If the return value is a Varargs, only the 1st value will be returned. To get multiple values, use LuaValue.invoke() instead.

To call this as a method call, use LuaValue.method(LuaValue) instead.

Specified by:

call in class OneArgFunction

Parameters:

arg - First argument to supply to the called function

Returns:

First return value (this(arg)), or NIL if there were none.

See Also:

LuaValue.call(), LuaValue.call(LuaValue,LuaValue), LuaValue.call(LuaValue, LuaValue, LuaValue), #invoke(LuaValue), LuaValue.method(String,LuaValue), LuaValue.method(LuaValue,LuaValue)

dpow

public static LuaValue dpow(double a,
                            double b)

compute power using installed math library, or default if there is no math library installed

dpow_d

public static double dpow_d(double a,
                            double b)

dpow_lib

public double dpow_lib(double a,
                       double b)

Hook to override default dpow behavior with faster implementation.

dpow_default

protected static double dpow_default(double a,
                                     double b)

Default JME version computes using longhand heuristics.