1/*
2** $Id: lmathlib.c $
3** Standard mathematical library
4** See Copyright Notice in lua.h
5*/
6
7#define lmathlib_c
8#define LUA_LIB
9
10#include "lprefix.h"
11
12
13#include <float.h>
14#include <limits.h>
15#include <math.h>
16#include <stdlib.h>
17#include <time.h>
18
19#include "lua.h"
20
21#include "lauxlib.h"
22#include "lualib.h"
23
24
25#undef PI
26#define PI (l_mathop(3.141592653589793238462643383279502884))
27
28
29static int math_abs (lua_State *L) {
30 if (lua_isinteger(L, 1)) {
31 lua_Integer n = lua_tointeger(L, 1);
32 if (n < 0) n = (lua_Integer)(0u - (lua_Unsigned)n);
33 lua_pushinteger(L, n);
34 }
35 else
36 lua_pushnumber(L, l_mathop(fabs)(luaL_checknumber(L, 1)));
37 return 1;
38}
39
40static int math_sin (lua_State *L) {
41 lua_pushnumber(L, l_mathop(sin)(luaL_checknumber(L, 1)));
42 return 1;
43}
44
45static int math_cos (lua_State *L) {
46 lua_pushnumber(L, l_mathop(cos)(luaL_checknumber(L, 1)));
47 return 1;
48}
49
50static int math_tan (lua_State *L) {
51 lua_pushnumber(L, l_mathop(tan)(luaL_checknumber(L, 1)));
52 return 1;
53}
54
55static int math_asin (lua_State *L) {
56 lua_pushnumber(L, l_mathop(asin)(luaL_checknumber(L, 1)));
57 return 1;
58}
59
60static int math_acos (lua_State *L) {
61 lua_pushnumber(L, l_mathop(acos)(luaL_checknumber(L, 1)));
62 return 1;
63}
64
65static int math_atan (lua_State *L) {
66 lua_Number y = luaL_checknumber(L, 1);
67 lua_Number x = luaL_optnumber(L, 2, 1);
68 lua_pushnumber(L, l_mathop(atan2)(y, x));
69 return 1;
70}
71
72
73static int math_toint (lua_State *L) {
74 int valid;
75 lua_Integer n = lua_tointegerx(L, 1, &valid);
76 if (l_likely(valid))
77 lua_pushinteger(L, n);
78 else {
79 luaL_checkany(L, 1);
80 luaL_pushfail(L); /* value is not convertible to integer */
81 }
82 return 1;
83}
84
85
86static void pushnumint (lua_State *L, lua_Number d) {
87 lua_Integer n;
88 if (lua_numbertointeger(d, &n)) /* does 'd' fit in an integer? */
89 lua_pushinteger(L, n); /* result is integer */
90 else
91 lua_pushnumber(L, d); /* result is float */
92}
93
94
95static int math_floor (lua_State *L) {
96 if (lua_isinteger(L, 1))
97 lua_settop(L, 1); /* integer is its own floor */
98 else {
99 lua_Number d = l_mathop(floor)(luaL_checknumber(L, 1));
100 pushnumint(L, d);
101 }
102 return 1;
103}
104
105
106static int math_ceil (lua_State *L) {
107 if (lua_isinteger(L, 1))
108 lua_settop(L, 1); /* integer is its own ceil */
109 else {
110 lua_Number d = l_mathop(ceil)(luaL_checknumber(L, 1));
111 pushnumint(L, d);
112 }
113 return 1;
114}
115
116
117static int math_fmod (lua_State *L) {
118 if (lua_isinteger(L, 1) && lua_isinteger(L, 2)) {
119 lua_Integer d = lua_tointeger(L, 2);
120 if ((lua_Unsigned)d + 1u <= 1u) { /* special cases: -1 or 0 */
121 luaL_argcheck(L, d != 0, 2, "zero");
122 lua_pushinteger(L, 0); /* avoid overflow with 0x80000... / -1 */
123 }
124 else
125 lua_pushinteger(L, lua_tointeger(L, 1) % d);
126 }
127 else
128 lua_pushnumber(L, l_mathop(fmod)(luaL_checknumber(L, 1),
129 luaL_checknumber(L, 2)));
130 return 1;
131}
132
133
134/*
135** next function does not use 'modf', avoiding problems with 'double*'
136** (which is not compatible with 'float*') when lua_Number is not
137** 'double'.
138*/
139static int math_modf (lua_State *L) {
140 if (lua_isinteger(L ,1)) {
141 lua_settop(L, 1); /* number is its own integer part */
142 lua_pushnumber(L, 0); /* no fractional part */
143 }
144 else {
145 lua_Number n = luaL_checknumber(L, 1);
146 /* integer part (rounds toward zero) */
147 lua_Number ip = (n < 0) ? l_mathop(ceil)(n) : l_mathop(floor)(n);
148 pushnumint(L, ip);
149 /* fractional part (test needed for inf/-inf) */
150 lua_pushnumber(L, (n == ip) ? l_mathop(0.0) : (n - ip));
151 }
152 return 2;
153}
154
155
156static int math_sqrt (lua_State *L) {
157 lua_pushnumber(L, l_mathop(sqrt)(luaL_checknumber(L, 1)));
158 return 1;
159}
160
161
162static int math_ult (lua_State *L) {
163 lua_Integer a = luaL_checkinteger(L, 1);
164 lua_Integer b = luaL_checkinteger(L, 2);
165 lua_pushboolean(L, (lua_Unsigned)a < (lua_Unsigned)b);
166 return 1;
167}
168
169static int math_log (lua_State *L) {
170 lua_Number x = luaL_checknumber(L, 1);
171 lua_Number res;
172 if (lua_isnoneornil(L, 2))
173 res = l_mathop(log)(x);
174 else {
175 lua_Number base = luaL_checknumber(L, 2);
176#if !defined(LUA_USE_C89)
177 if (base == l_mathop(2.0))
178 res = l_mathop(log2)(x);
179 else
180#endif
181 if (base == l_mathop(10.0))
182 res = l_mathop(log10)(x);
183 else
184 res = l_mathop(log)(x)/l_mathop(log)(base);
185 }
186 lua_pushnumber(L, res);
187 return 1;
188}
189
190static int math_exp (lua_State *L) {
191 lua_pushnumber(L, l_mathop(exp)(luaL_checknumber(L, 1)));
192 return 1;
193}
194
195static int math_deg (lua_State *L) {
196 lua_pushnumber(L, luaL_checknumber(L, 1) * (l_mathop(180.0) / PI));
197 return 1;
198}
199
200static int math_rad (lua_State *L) {
201 lua_pushnumber(L, luaL_checknumber(L, 1) * (PI / l_mathop(180.0)));
202 return 1;
203}
204
205
206static int math_min (lua_State *L) {
207 int n = lua_gettop(L); /* number of arguments */
208 int imin = 1; /* index of current minimum value */
209 int i;
210 luaL_argcheck(L, n >= 1, 1, "value expected");
211 for (i = 2; i <= n; i++) {
212 if (lua_compare(L, i, imin, LUA_OPLT))
213 imin = i;
214 }
215 lua_pushvalue(L, imin);
216 return 1;
217}
218
219
220static int math_max (lua_State *L) {
221 int n = lua_gettop(L); /* number of arguments */
222 int imax = 1; /* index of current maximum value */
223 int i;
224 luaL_argcheck(L, n >= 1, 1, "value expected");
225 for (i = 2; i <= n; i++) {
226 if (lua_compare(L, imax, i, LUA_OPLT))
227 imax = i;
228 }
229 lua_pushvalue(L, imax);
230 return 1;
231}
232
233
234static int math_type (lua_State *L) {
235 if (lua_type(L, 1) == LUA_TNUMBER)
236 lua_pushstring(L, (lua_isinteger(L, 1)) ? "integer" : "float");
237 else {
238 luaL_checkany(L, 1);
239 luaL_pushfail(L);
240 }
241 return 1;
242}
243
244
245
246/*
247** {==================================================================
248** Pseudo-Random Number Generator based on 'xoshiro256**'.
249** ===================================================================
250*/
251
252/*
253** This code uses lots of shifts. ANSI C does not allow shifts greater
254** than or equal to the width of the type being shifted, so some shifts
255** are written in convoluted ways to match that restriction. For
256** preprocessor tests, it assumes a width of 32 bits, so the maximum
257** shift there is 31 bits.
258*/
259
260
261/* number of binary digits in the mantissa of a float */
262#define FIGS l_floatatt(MANT_DIG)
263
264#if FIGS > 64
265/* there are only 64 random bits; use them all */
266#undef FIGS
267#define FIGS 64
268#endif
269
270
271/*
272** LUA_RAND32 forces the use of 32-bit integers in the implementation
273** of the PRN generator (mainly for testing).
274*/
275#if !defined(LUA_RAND32) && !defined(Rand64)
276
277/* try to find an integer type with at least 64 bits */
278
279#if ((ULONG_MAX >> 31) >> 31) >= 3
280
281/* 'long' has at least 64 bits */
282#define Rand64 unsigned long
283#define SRand64 long
284
285#elif !defined(LUA_USE_C89) && defined(LLONG_MAX)
286
287/* there is a 'long long' type (which must have at least 64 bits) */
288#define Rand64 unsigned long long
289#define SRand64 long long
290
291#elif ((LUA_MAXUNSIGNED >> 31) >> 31) >= 3
292
293/* 'lua_Unsigned' has at least 64 bits */
294#define Rand64 lua_Unsigned
295#define SRand64 lua_Integer
296
297#endif
298
299#endif
300
301
302#if defined(Rand64) /* { */
303
304/*
305** Standard implementation, using 64-bit integers.
306** If 'Rand64' has more than 64 bits, the extra bits do not interfere
307** with the 64 initial bits, except in a right shift. Moreover, the
308** final result has to discard the extra bits.
309*/
310
311/* avoid using extra bits when needed */
312#define trim64(x) ((x) & 0xffffffffffffffffu)
313
314
315/* rotate left 'x' by 'n' bits */
316static Rand64 rotl (Rand64 x, int n) {
317 return (x << n) | (trim64(x) >> (64 - n));
318}
319
320static Rand64 nextrand (Rand64 *state) {
321 Rand64 state0 = state[0];
322 Rand64 state1 = state[1];
323 Rand64 state2 = state[2] ^ state0;
324 Rand64 state3 = state[3] ^ state1;
325 Rand64 res = rotl(state1 * 5, 7) * 9;
326 state[0] = state0 ^ state3;
327 state[1] = state1 ^ state2;
328 state[2] = state2 ^ (state1 << 17);
329 state[3] = rotl(state3, 45);
330 return res;
331}
332
333
334/*
335** Convert bits from a random integer into a float in the
336** interval [0,1), getting the higher FIG bits from the
337** random unsigned integer and converting that to a float.
338** Some old Microsoft compilers cannot cast an unsigned long
339** to a floating-point number, so we use a signed long as an
340** intermediary. When lua_Number is float or double, the shift ensures
341** that 'sx' is non negative; in that case, a good compiler will remove
342** the correction.
343*/
344
345/* must throw out the extra (64 - FIGS) bits */
346#define shift64_FIG (64 - FIGS)
347
348/* 2^(-FIGS) == 2^-1 / 2^(FIGS-1) */
349#define scaleFIG (l_mathop(0.5) / ((Rand64)1 << (FIGS - 1)))
350
351static lua_Number I2d (Rand64 x) {
352 SRand64 sx = (SRand64)(trim64(x) >> shift64_FIG);
353 lua_Number res = (lua_Number)(sx) * scaleFIG;
354 if (sx < 0)
355 res += l_mathop(1.0); /* correct the two's complement if negative */
356 lua_assert(0 <= res && res < 1);
357 return res;
358}
359
360/* convert a 'Rand64' to a 'lua_Unsigned' */
361#define I2UInt(x) ((lua_Unsigned)trim64(x))
362
363/* convert a 'lua_Unsigned' to a 'Rand64' */
364#define Int2I(x) ((Rand64)(x))
365
366
367#else /* no 'Rand64' }{ */
368
369/* get an integer with at least 32 bits */
370#if LUAI_IS32INT
371typedef unsigned int lu_int32;
372#else
373typedef unsigned long lu_int32;
374#endif
375
376
377/*
378** Use two 32-bit integers to represent a 64-bit quantity.
379*/
380typedef struct Rand64 {
381 lu_int32 h; /* higher half */
382 lu_int32 l; /* lower half */
383} Rand64;
384
385
386/*
387** If 'lu_int32' has more than 32 bits, the extra bits do not interfere
388** with the 32 initial bits, except in a right shift and comparisons.
389** Moreover, the final result has to discard the extra bits.
390*/
391
392/* avoid using extra bits when needed */
393#define trim32(x) ((x) & 0xffffffffu)
394
395
396/*
397** basic operations on 'Rand64' values
398*/
399
400/* build a new Rand64 value */
401static Rand64 packI (lu_int32 h, lu_int32 l) {
402 Rand64 result;
403 result.h = h;
404 result.l = l;
405 return result;
406}
407
408/* return i << n */
409static Rand64 Ishl (Rand64 i, int n) {
410 lua_assert(n > 0 && n < 32);
411 return packI((i.h << n) | (trim32(i.l) >> (32 - n)), i.l << n);
412}
413
414/* i1 ^= i2 */
415static void Ixor (Rand64 *i1, Rand64 i2) {
416 i1->h ^= i2.h;
417 i1->l ^= i2.l;
418}
419
420/* return i1 + i2 */
421static Rand64 Iadd (Rand64 i1, Rand64 i2) {
422 Rand64 result = packI(i1.h + i2.h, i1.l + i2.l);
423 if (trim32(result.l) < trim32(i1.l)) /* carry? */
424 result.h++;
425 return result;
426}
427
428/* return i * 5 */
429static Rand64 times5 (Rand64 i) {
430 return Iadd(Ishl(i, 2), i); /* i * 5 == (i << 2) + i */
431}
432
433/* return i * 9 */
434static Rand64 times9 (Rand64 i) {
435 return Iadd(Ishl(i, 3), i); /* i * 9 == (i << 3) + i */
436}
437
438/* return 'i' rotated left 'n' bits */
439static Rand64 rotl (Rand64 i, int n) {
440 lua_assert(n > 0 && n < 32);
441 return packI((i.h << n) | (trim32(i.l) >> (32 - n)),
442 (trim32(i.h) >> (32 - n)) | (i.l << n));
443}
444
445/* for offsets larger than 32, rotate right by 64 - offset */
446static Rand64 rotl1 (Rand64 i, int n) {
447 lua_assert(n > 32 && n < 64);
448 n = 64 - n;
449 return packI((trim32(i.h) >> n) | (i.l << (32 - n)),
450 (i.h << (32 - n)) | (trim32(i.l) >> n));
451}
452
453/*
454** implementation of 'xoshiro256**' algorithm on 'Rand64' values
455*/
456static Rand64 nextrand (Rand64 *state) {
457 Rand64 res = times9(rotl(times5(state[1]), 7));
458 Rand64 t = Ishl(state[1], 17);
459 Ixor(&state[2], state[0]);
460 Ixor(&state[3], state[1]);
461 Ixor(&state[1], state[2]);
462 Ixor(&state[0], state[3]);
463 Ixor(&state[2], t);
464 state[3] = rotl1(state[3], 45);
465 return res;
466}
467
468
469/*
470** Converts a 'Rand64' into a float.
471*/
472
473/* an unsigned 1 with proper type */
474#define UONE ((lu_int32)1)
475
476
477#if FIGS <= 32
478
479/* 2^(-FIGS) */
480#define scaleFIG (l_mathop(0.5) / (UONE << (FIGS - 1)))
481
482/*
483** get up to 32 bits from higher half, shifting right to
484** throw out the extra bits.
485*/
486static lua_Number I2d (Rand64 x) {
487 lua_Number h = (lua_Number)(trim32(x.h) >> (32 - FIGS));
488 return h * scaleFIG;
489}
490
491#else /* 32 < FIGS <= 64 */
492
493/* 2^(-FIGS) = 1.0 / 2^30 / 2^3 / 2^(FIGS-33) */
494#define scaleFIG \
495 (l_mathop(1.0) / (UONE << 30) / l_mathop(8.0) / (UONE << (FIGS - 33)))
496
497/*
498** use FIGS - 32 bits from lower half, throwing out the other
499** (32 - (FIGS - 32)) = (64 - FIGS) bits
500*/
501#define shiftLOW (64 - FIGS)
502
503/*
504** higher 32 bits go after those (FIGS - 32) bits: shiftHI = 2^(FIGS - 32)
505*/
506#define shiftHI ((lua_Number)(UONE << (FIGS - 33)) * l_mathop(2.0))
507
508
509static lua_Number I2d (Rand64 x) {
510 lua_Number h = (lua_Number)trim32(x.h) * shiftHI;
511 lua_Number l = (lua_Number)(trim32(x.l) >> shiftLOW);
512 return (h + l) * scaleFIG;
513}
514
515#endif
516
517
518/* convert a 'Rand64' to a 'lua_Unsigned' */
519static lua_Unsigned I2UInt (Rand64 x) {
520 return (((lua_Unsigned)trim32(x.h) << 31) << 1) | (lua_Unsigned)trim32(x.l);
521}
522
523/* convert a 'lua_Unsigned' to a 'Rand64' */
524static Rand64 Int2I (lua_Unsigned n) {
525 return packI((lu_int32)((n >> 31) >> 1), (lu_int32)n);
526}
527
528#endif /* } */
529
530
531/*
532** A state uses four 'Rand64' values.
533*/
534typedef struct {
535 Rand64 s[4];
536} RanState;
537
538
539/*
540** Project the random integer 'ran' into the interval [0, n].
541** Because 'ran' has 2^B possible values, the projection can only be
542** uniform when the size of the interval is a power of 2 (exact
543** division). Otherwise, to get a uniform projection into [0, n], we
544** first compute 'lim', the smallest Mersenne number not smaller than
545** 'n'. We then project 'ran' into the interval [0, lim]. If the result
546** is inside [0, n], we are done. Otherwise, we try with another 'ran',
547** until we have a result inside the interval.
548*/
549static lua_Unsigned project (lua_Unsigned ran, lua_Unsigned n,
550 RanState *state) {
551 if ((n & (n + 1)) == 0) /* is 'n + 1' a power of 2? */
552 return ran & n; /* no bias */
553 else {
554 lua_Unsigned lim = n;
555 /* compute the smallest (2^b - 1) not smaller than 'n' */
556 lim |= (lim >> 1);
557 lim |= (lim >> 2);
558 lim |= (lim >> 4);
559 lim |= (lim >> 8);
560 lim |= (lim >> 16);
561#if (LUA_MAXUNSIGNED >> 31) >= 3
562 lim |= (lim >> 32); /* integer type has more than 32 bits */
563#endif
564 lua_assert((lim & (lim + 1)) == 0 /* 'lim + 1' is a power of 2, */
565 && lim >= n /* not smaller than 'n', */
566 && (lim >> 1) < n); /* and it is the smallest one */
567 while ((ran &= lim) > n) /* project 'ran' into [0..lim] */
568 ran = I2UInt(nextrand(state->s)); /* not inside [0..n]? try again */
569 return ran;
570 }
571}
572
573
574static int math_random (lua_State *L) {
575 lua_Integer low, up;
576 lua_Unsigned p;
577 RanState *state = (RanState *)lua_touserdata(L, lua_upvalueindex(1));
578 Rand64 rv = nextrand(state->s); /* next pseudo-random value */
579 switch (lua_gettop(L)) { /* check number of arguments */
580 case 0: { /* no arguments */
581 lua_pushnumber(L, I2d(rv)); /* float between 0 and 1 */
582 return 1;
583 }
584 case 1: { /* only upper limit */
585 low = 1;
586 up = luaL_checkinteger(L, 1);
587 if (up == 0) { /* single 0 as argument? */
588 lua_pushinteger(L, I2UInt(rv)); /* full random integer */
589 return 1;
590 }
591 break;
592 }
593 case 2: { /* lower and upper limits */
594 low = luaL_checkinteger(L, 1);
595 up = luaL_checkinteger(L, 2);
596 break;
597 }
598 default: return luaL_error(L, "wrong number of arguments");
599 }
600 /* random integer in the interval [low, up] */
601 luaL_argcheck(L, low <= up, 1, "interval is empty");
602 /* project random integer into the interval [0, up - low] */
603 p = project(I2UInt(rv), (lua_Unsigned)up - (lua_Unsigned)low, state);
604 lua_pushinteger(L, p + (lua_Unsigned)low);
605 return 1;
606}
607
608
609static void setseed (lua_State *L, Rand64 *state,
610 lua_Unsigned n1, lua_Unsigned n2) {
611 int i;
612 state[0] = Int2I(n1);
613 state[1] = Int2I(0xff); /* avoid a zero state */
614 state[2] = Int2I(n2);
615 state[3] = Int2I(0);
616 for (i = 0; i < 16; i++)
617 nextrand(state); /* discard initial values to "spread" seed */
618 lua_pushinteger(L, n1);
619 lua_pushinteger(L, n2);
620}
621
622
623/*
624** Set a "random" seed. To get some randomness, use the current time
625** and the address of 'L' (in case the machine does address space layout
626** randomization).
627*/
628static void randseed (lua_State *L, RanState *state) {
629 lua_Unsigned seed1 = (lua_Unsigned)time(NULL);
630 lua_Unsigned seed2 = (lua_Unsigned)(size_t)L;
631 setseed(L, state->s, seed1, seed2);
632}
633
634
635static int math_randomseed (lua_State *L) {
636 RanState *state = (RanState *)lua_touserdata(L, lua_upvalueindex(1));
637 if (lua_isnone(L, 1)) {
638 randseed(L, state);
639 }
640 else {
641 lua_Integer n1 = luaL_checkinteger(L, 1);
642 lua_Integer n2 = luaL_optinteger(L, 2, 0);
643 setseed(L, state->s, n1, n2);
644 }
645 return 2; /* return seeds */
646}
647
648
649static const luaL_Reg randfuncs[] = {
650 {"random", math_random},
651 {"randomseed", math_randomseed},
652 {NULL, NULL}
653};
654
655
656/*
657** Register the random functions and initialize their state.
658*/
659static void setrandfunc (lua_State *L) {
660 RanState *state = (RanState *)lua_newuserdatauv(L, sizeof(RanState), 0);
661 randseed(L, state); /* initialize with a "random" seed */
662 lua_pop(L, 2); /* remove pushed seeds */
663 luaL_setfuncs(L, randfuncs, 1);
664}
665
666/* }================================================================== */
667
668
669/*
670** {==================================================================
671** Deprecated functions (for compatibility only)
672** ===================================================================
673*/
674#if defined(LUA_COMPAT_MATHLIB)
675
676static int math_cosh (lua_State *L) {
677 lua_pushnumber(L, l_mathop(cosh)(luaL_checknumber(L, 1)));
678 return 1;
679}
680
681static int math_sinh (lua_State *L) {
682 lua_pushnumber(L, l_mathop(sinh)(luaL_checknumber(L, 1)));
683 return 1;
684}
685
686static int math_tanh (lua_State *L) {
687 lua_pushnumber(L, l_mathop(tanh)(luaL_checknumber(L, 1)));
688 return 1;
689}
690
691static int math_pow (lua_State *L) {
692 lua_Number x = luaL_checknumber(L, 1);
693 lua_Number y = luaL_checknumber(L, 2);
694 lua_pushnumber(L, l_mathop(pow)(x, y));
695 return 1;
696}
697
698static int math_frexp (lua_State *L) {
699 int e;
700 lua_pushnumber(L, l_mathop(frexp)(luaL_checknumber(L, 1), &e));
701 lua_pushinteger(L, e);
702 return 2;
703}
704
705static int math_ldexp (lua_State *L) {
706 lua_Number x = luaL_checknumber(L, 1);
707 int ep = (int)luaL_checkinteger(L, 2);
708 lua_pushnumber(L, l_mathop(ldexp)(x, ep));
709 return 1;
710}
711
712static int math_log10 (lua_State *L) {
713 lua_pushnumber(L, l_mathop(log10)(luaL_checknumber(L, 1)));
714 return 1;
715}
716
717#endif
718/* }================================================================== */
719
720
721
722static const luaL_Reg mathlib[] = {
723 {"abs", math_abs},
724 {"acos", math_acos},
725 {"asin", math_asin},
726 {"atan", math_atan},
727 {"ceil", math_ceil},
728 {"cos", math_cos},
729 {"deg", math_deg},
730 {"exp", math_exp},
731 {"tointeger", math_toint},
732 {"floor", math_floor},
733 {"fmod", math_fmod},
734 {"ult", math_ult},
735 {"log", math_log},
736 {"max", math_max},
737 {"min", math_min},
738 {"modf", math_modf},
739 {"rad", math_rad},
740 {"sin", math_sin},
741 {"sqrt", math_sqrt},
742 {"tan", math_tan},
743 {"type", math_type},
744#if defined(LUA_COMPAT_MATHLIB)
745 {"atan2", math_atan},
746 {"cosh", math_cosh},
747 {"sinh", math_sinh},
748 {"tanh", math_tanh},
749 {"pow", math_pow},
750 {"frexp", math_frexp},
751 {"ldexp", math_ldexp},
752 {"log10", math_log10},
753#endif
754 /* placeholders */
755 {"random", NULL},
756 {"randomseed", NULL},
757 {"pi", NULL},
758 {"huge", NULL},
759 {"maxinteger", NULL},
760 {"mininteger", NULL},
761 {NULL, NULL}
762};
763
764
765/*
766** Open math library
767*/
768LUAMOD_API int luaopen_math (lua_State *L) {
769 luaL_newlib(L, mathlib);
770 lua_pushnumber(L, PI);
771 lua_setfield(L, -2, "pi");
772 lua_pushnumber(L, (lua_Number)HUGE_VAL);
773 lua_setfield(L, -2, "huge");
774 lua_pushinteger(L, LUA_MAXINTEGER);
775 lua_setfield(L, -2, "maxinteger");
776 lua_pushinteger(L, LUA_MININTEGER);
777 lua_setfield(L, -2, "mininteger");
778 setrandfunc(L);
779 return 1;
780}
781