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