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 (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
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);
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
math_exp(lua_State * L)190 static int math_exp (lua_State *L) {
191 lua_pushnumber(L, l_mathop(exp)(luaL_checknumber(L, 1)));
192 return 1;
193 }
194
math_deg(lua_State * L)195 static int math_deg (lua_State *L) {
196 lua_pushnumber(L, luaL_checknumber(L, 1) * (l_mathop(180.0) / PI));
197 return 1;
198 }
199
math_rad(lua_State * L)200 static 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
math_min(lua_State * L)206 static 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
math_max(lua_State * L)220 static 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
math_type(lua_State * L)234 static 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 /* number of binary digits in the mantissa of a float */
253 #define FIGS l_floatatt(MANT_DIG)
254
255 #if FIGS > 64
256 /* there are only 64 random bits; use them all */
257 #undef FIGS
258 #define FIGS 64
259 #endif
260
261
262 /*
263 ** LUA_RAND32 forces the use of 32-bit integers in the implementation
264 ** of the PRN generator (mainly for testing).
265 */
266 #if !defined(LUA_RAND32) && !defined(Rand64)
267
268 /* try to find an integer type with at least 64 bits */
269
270 #if ((ULONG_MAX >> 31) >> 31) >= 3
271
272 /* 'long' has at least 64 bits */
273 #define Rand64 unsigned long
274
275 #elif !defined(LUA_USE_C89) && defined(LLONG_MAX)
276
277 /* there is a 'long long' type (which must have at least 64 bits) */
278 #define Rand64 unsigned long long
279
280 #elif ((LUA_MAXUNSIGNED >> 31) >> 31) >= 3
281
282 /* 'lua_Unsigned' has at least 64 bits */
283 #define Rand64 lua_Unsigned
284
285 #endif
286
287 #endif
288
289
290 #if defined(Rand64) /* { */
291
292 /*
293 ** Standard implementation, using 64-bit integers.
294 ** If 'Rand64' has more than 64 bits, the extra bits do not interfere
295 ** with the 64 initial bits, except in a right shift. Moreover, the
296 ** final result has to discard the extra bits.
297 */
298
299 /* avoid using extra bits when needed */
300 #define trim64(x) ((x) & 0xffffffffffffffffu)
301
302
303 /* rotate left 'x' by 'n' bits */
rotl(Rand64 x,int n)304 static Rand64 rotl (Rand64 x, int n) {
305 return (x << n) | (trim64(x) >> (64 - n));
306 }
307
nextrand(Rand64 * state)308 static Rand64 nextrand (Rand64 *state) {
309 Rand64 state0 = state[0];
310 Rand64 state1 = state[1];
311 Rand64 state2 = state[2] ^ state0;
312 Rand64 state3 = state[3] ^ state1;
313 Rand64 res = rotl(state1 * 5, 7) * 9;
314 state[0] = state0 ^ state3;
315 state[1] = state1 ^ state2;
316 state[2] = state2 ^ (state1 << 17);
317 state[3] = rotl(state3, 45);
318 return res;
319 }
320
321
322 /* must take care to not shift stuff by more than 63 slots */
323
324
325 /*
326 ** Convert bits from a random integer into a float in the
327 ** interval [0,1), getting the higher FIG bits from the
328 ** random unsigned integer and converting that to a float.
329 */
330
331 /* must throw out the extra (64 - FIGS) bits */
332 #define shift64_FIG (64 - FIGS)
333
334 /* to scale to [0, 1), multiply by scaleFIG = 2^(-FIGS) */
335 #define scaleFIG (l_mathop(0.5) / ((Rand64)1 << (FIGS - 1)))
336
I2d(Rand64 x)337 static lua_Number I2d (Rand64 x) {
338 return (lua_Number)(trim64(x) >> shift64_FIG) * scaleFIG;
339 }
340
341 /* convert a 'Rand64' to a 'lua_Unsigned' */
342 #define I2UInt(x) ((lua_Unsigned)trim64(x))
343
344 /* convert a 'lua_Unsigned' to a 'Rand64' */
345 #define Int2I(x) ((Rand64)(x))
346
347
348 #else /* no 'Rand64' }{ */
349
350 /* get an integer with at least 32 bits */
351 #if LUAI_IS32INT
352 typedef unsigned int lu_int32;
353 #else
354 typedef unsigned long lu_int32;
355 #endif
356
357
358 /*
359 ** Use two 32-bit integers to represent a 64-bit quantity.
360 */
361 typedef struct Rand64 {
362 lu_int32 h; /* higher half */
363 lu_int32 l; /* lower half */
364 } Rand64;
365
366
367 /*
368 ** If 'lu_int32' has more than 32 bits, the extra bits do not interfere
369 ** with the 32 initial bits, except in a right shift and comparisons.
370 ** Moreover, the final result has to discard the extra bits.
371 */
372
373 /* avoid using extra bits when needed */
374 #define trim32(x) ((x) & 0xffffffffu)
375
376
377 /*
378 ** basic operations on 'Rand64' values
379 */
380
381 /* build a new Rand64 value */
packI(lu_int32 h,lu_int32 l)382 static Rand64 packI (lu_int32 h, lu_int32 l) {
383 Rand64 result;
384 result.h = h;
385 result.l = l;
386 return result;
387 }
388
389 /* return i << n */
Ishl(Rand64 i,int n)390 static Rand64 Ishl (Rand64 i, int n) {
391 lua_assert(n > 0 && n < 32);
392 return packI((i.h << n) | (trim32(i.l) >> (32 - n)), i.l << n);
393 }
394
395 /* i1 ^= i2 */
Ixor(Rand64 * i1,Rand64 i2)396 static void Ixor (Rand64 *i1, Rand64 i2) {
397 i1->h ^= i2.h;
398 i1->l ^= i2.l;
399 }
400
401 /* return i1 + i2 */
Iadd(Rand64 i1,Rand64 i2)402 static Rand64 Iadd (Rand64 i1, Rand64 i2) {
403 Rand64 result = packI(i1.h + i2.h, i1.l + i2.l);
404 if (trim32(result.l) < trim32(i1.l)) /* carry? */
405 result.h++;
406 return result;
407 }
408
409 /* return i * 5 */
times5(Rand64 i)410 static Rand64 times5 (Rand64 i) {
411 return Iadd(Ishl(i, 2), i); /* i * 5 == (i << 2) + i */
412 }
413
414 /* return i * 9 */
times9(Rand64 i)415 static Rand64 times9 (Rand64 i) {
416 return Iadd(Ishl(i, 3), i); /* i * 9 == (i << 3) + i */
417 }
418
419 /* return 'i' rotated left 'n' bits */
rotl(Rand64 i,int n)420 static Rand64 rotl (Rand64 i, int n) {
421 lua_assert(n > 0 && n < 32);
422 return packI((i.h << n) | (trim32(i.l) >> (32 - n)),
423 (trim32(i.h) >> (32 - n)) | (i.l << n));
424 }
425
426 /* for offsets larger than 32, rotate right by 64 - offset */
rotl1(Rand64 i,int n)427 static Rand64 rotl1 (Rand64 i, int n) {
428 lua_assert(n > 32 && n < 64);
429 n = 64 - n;
430 return packI((trim32(i.h) >> n) | (i.l << (32 - n)),
431 (i.h << (32 - n)) | (trim32(i.l) >> n));
432 }
433
434 /*
435 ** implementation of 'xoshiro256**' algorithm on 'Rand64' values
436 */
nextrand(Rand64 * state)437 static Rand64 nextrand (Rand64 *state) {
438 Rand64 res = times9(rotl(times5(state[1]), 7));
439 Rand64 t = Ishl(state[1], 17);
440 Ixor(&state[2], state[0]);
441 Ixor(&state[3], state[1]);
442 Ixor(&state[1], state[2]);
443 Ixor(&state[0], state[3]);
444 Ixor(&state[2], t);
445 state[3] = rotl1(state[3], 45);
446 return res;
447 }
448
449
450 /*
451 ** Converts a 'Rand64' into a float.
452 */
453
454 /* an unsigned 1 with proper type */
455 #define UONE ((lu_int32)1)
456
457
458 #if FIGS <= 32
459
460 /* 2^(-FIGS) */
461 #define scaleFIG (l_mathop(0.5) / (UONE << (FIGS - 1)))
462
463 /*
464 ** get up to 32 bits from higher half, shifting right to
465 ** throw out the extra bits.
466 */
I2d(Rand64 x)467 static lua_Number I2d (Rand64 x) {
468 lua_Number h = (lua_Number)(trim32(x.h) >> (32 - FIGS));
469 return h * scaleFIG;
470 }
471
472 #else /* 32 < FIGS <= 64 */
473
474 /* must take care to not shift stuff by more than 31 slots */
475
476 /* 2^(-FIGS) = 1.0 / 2^30 / 2^3 / 2^(FIGS-33) */
477 #define scaleFIG \
478 (l_mathop(1.0) / (UONE << 30) / l_mathop(8.0) / (UONE << (FIGS - 33)))
479
480 /*
481 ** use FIGS - 32 bits from lower half, throwing out the other
482 ** (32 - (FIGS - 32)) = (64 - FIGS) bits
483 */
484 #define shiftLOW (64 - FIGS)
485
486 /*
487 ** higher 32 bits go after those (FIGS - 32) bits: shiftHI = 2^(FIGS - 32)
488 */
489 #define shiftHI ((lua_Number)(UONE << (FIGS - 33)) * l_mathop(2.0))
490
491
I2d(Rand64 x)492 static lua_Number I2d (Rand64 x) {
493 lua_Number h = (lua_Number)trim32(x.h) * shiftHI;
494 lua_Number l = (lua_Number)(trim32(x.l) >> shiftLOW);
495 return (h + l) * scaleFIG;
496 }
497
498 #endif
499
500
501 /* convert a 'Rand64' to a 'lua_Unsigned' */
I2UInt(Rand64 x)502 static lua_Unsigned I2UInt (Rand64 x) {
503 return (((lua_Unsigned)trim32(x.h) << 31) << 1) | (lua_Unsigned)trim32(x.l);
504 }
505
506 /* convert a 'lua_Unsigned' to a 'Rand64' */
Int2I(lua_Unsigned n)507 static Rand64 Int2I (lua_Unsigned n) {
508 return packI((lu_int32)((n >> 31) >> 1), (lu_int32)n);
509 }
510
511 #endif /* } */
512
513
514 /*
515 ** A state uses four 'Rand64' values.
516 */
517 typedef struct {
518 Rand64 s[4];
519 } RanState;
520
521
522 /*
523 ** Project the random integer 'ran' into the interval [0, n].
524 ** Because 'ran' has 2^B possible values, the projection can only be
525 ** uniform when the size of the interval is a power of 2 (exact
526 ** division). Otherwise, to get a uniform projection into [0, n], we
527 ** first compute 'lim', the smallest Mersenne number not smaller than
528 ** 'n'. We then project 'ran' into the interval [0, lim]. If the result
529 ** is inside [0, n], we are done. Otherwise, we try with another 'ran',
530 ** until we have a result inside the interval.
531 */
project(lua_Unsigned ran,lua_Unsigned n,RanState * state)532 static lua_Unsigned project (lua_Unsigned ran, lua_Unsigned n,
533 RanState *state) {
534 if ((n & (n + 1)) == 0) /* is 'n + 1' a power of 2? */
535 return ran & n; /* no bias */
536 else {
537 lua_Unsigned lim = n;
538 /* compute the smallest (2^b - 1) not smaller than 'n' */
539 lim |= (lim >> 1);
540 lim |= (lim >> 2);
541 lim |= (lim >> 4);
542 lim |= (lim >> 8);
543 lim |= (lim >> 16);
544 #if (LUA_MAXUNSIGNED >> 31) >= 3
545 lim |= (lim >> 32); /* integer type has more than 32 bits */
546 #endif
547 lua_assert((lim & (lim + 1)) == 0 /* 'lim + 1' is a power of 2, */
548 && lim >= n /* not smaller than 'n', */
549 && (lim >> 1) < n); /* and it is the smallest one */
550 while ((ran &= lim) > n) /* project 'ran' into [0..lim] */
551 ran = I2UInt(nextrand(state->s)); /* not inside [0..n]? try again */
552 return ran;
553 }
554 }
555
556
math_random(lua_State * L)557 static int math_random (lua_State *L) {
558 lua_Integer low, up;
559 lua_Unsigned p;
560 RanState *state = (RanState *)lua_touserdata(L, lua_upvalueindex(1));
561 Rand64 rv = nextrand(state->s); /* next pseudo-random value */
562 switch (lua_gettop(L)) { /* check number of arguments */
563 case 0: { /* no arguments */
564 lua_pushnumber(L, I2d(rv)); /* float between 0 and 1 */
565 return 1;
566 }
567 case 1: { /* only upper limit */
568 low = 1;
569 up = luaL_checkinteger(L, 1);
570 if (up == 0) { /* single 0 as argument? */
571 lua_pushinteger(L, I2UInt(rv)); /* full random integer */
572 return 1;
573 }
574 break;
575 }
576 case 2: { /* lower and upper limits */
577 low = luaL_checkinteger(L, 1);
578 up = luaL_checkinteger(L, 2);
579 break;
580 }
581 default: return luaL_error(L, "wrong number of arguments");
582 }
583 /* random integer in the interval [low, up] */
584 luaL_argcheck(L, low <= up, 1, "interval is empty");
585 /* project random integer into the interval [0, up - low] */
586 p = project(I2UInt(rv), (lua_Unsigned)up - (lua_Unsigned)low, state);
587 lua_pushinteger(L, p + (lua_Unsigned)low);
588 return 1;
589 }
590
591
setseed(lua_State * L,Rand64 * state,lua_Unsigned n1,lua_Unsigned n2)592 static void setseed (lua_State *L, Rand64 *state,
593 lua_Unsigned n1, lua_Unsigned n2) {
594 int i;
595 state[0] = Int2I(n1);
596 state[1] = Int2I(0xff); /* avoid a zero state */
597 state[2] = Int2I(n2);
598 state[3] = Int2I(0);
599 for (i = 0; i < 16; i++)
600 nextrand(state); /* discard initial values to "spread" seed */
601 lua_pushinteger(L, n1);
602 lua_pushinteger(L, n2);
603 }
604
605
606 /*
607 ** Set a "random" seed. To get some randomness, use the current time
608 ** and the address of 'L' (in case the machine does address space layout
609 ** randomization).
610 */
randseed(lua_State * L,RanState * state)611 static void randseed (lua_State *L, RanState *state) {
612 lua_Unsigned seed1 = (lua_Unsigned)time(NULL);
613 lua_Unsigned seed2 = (lua_Unsigned)(size_t)L;
614 setseed(L, state->s, seed1, seed2);
615 }
616
617
math_randomseed(lua_State * L)618 static int math_randomseed (lua_State *L) {
619 RanState *state = (RanState *)lua_touserdata(L, lua_upvalueindex(1));
620 if (lua_isnone(L, 1)) {
621 randseed(L, state);
622 }
623 else {
624 lua_Integer n1 = luaL_checkinteger(L, 1);
625 lua_Integer n2 = luaL_optinteger(L, 2, 0);
626 setseed(L, state->s, n1, n2);
627 }
628 return 2; /* return seeds */
629 }
630
631
632 static const luaL_Reg randfuncs[] = {
633 {"random", math_random},
634 {"randomseed", math_randomseed},
635 {NULL, NULL}
636 };
637
638
639 /*
640 ** Register the random functions and initialize their state.
641 */
setrandfunc(lua_State * L)642 static void setrandfunc (lua_State *L) {
643 RanState *state = (RanState *)lua_newuserdatauv(L, sizeof(RanState), 0);
644 randseed(L, state); /* initialize with a "random" seed */
645 lua_pop(L, 2); /* remove pushed seeds */
646 luaL_setfuncs(L, randfuncs, 1);
647 }
648
649 /* }================================================================== */
650
651
652 /*
653 ** {==================================================================
654 ** Deprecated functions (for compatibility only)
655 ** ===================================================================
656 */
657 #if defined(LUA_COMPAT_MATHLIB)
658
math_cosh(lua_State * L)659 static int math_cosh (lua_State *L) {
660 lua_pushnumber(L, l_mathop(cosh)(luaL_checknumber(L, 1)));
661 return 1;
662 }
663
math_sinh(lua_State * L)664 static int math_sinh (lua_State *L) {
665 lua_pushnumber(L, l_mathop(sinh)(luaL_checknumber(L, 1)));
666 return 1;
667 }
668
math_tanh(lua_State * L)669 static int math_tanh (lua_State *L) {
670 lua_pushnumber(L, l_mathop(tanh)(luaL_checknumber(L, 1)));
671 return 1;
672 }
673
math_pow(lua_State * L)674 static int math_pow (lua_State *L) {
675 lua_Number x = luaL_checknumber(L, 1);
676 lua_Number y = luaL_checknumber(L, 2);
677 lua_pushnumber(L, l_mathop(pow)(x, y));
678 return 1;
679 }
680
math_frexp(lua_State * L)681 static int math_frexp (lua_State *L) {
682 int e;
683 lua_pushnumber(L, l_mathop(frexp)(luaL_checknumber(L, 1), &e));
684 lua_pushinteger(L, e);
685 return 2;
686 }
687
math_ldexp(lua_State * L)688 static int math_ldexp (lua_State *L) {
689 lua_Number x = luaL_checknumber(L, 1);
690 int ep = (int)luaL_checkinteger(L, 2);
691 lua_pushnumber(L, l_mathop(ldexp)(x, ep));
692 return 1;
693 }
694
math_log10(lua_State * L)695 static int math_log10 (lua_State *L) {
696 lua_pushnumber(L, l_mathop(log10)(luaL_checknumber(L, 1)));
697 return 1;
698 }
699
700 #endif
701 /* }================================================================== */
702
703
704
705 static const luaL_Reg mathlib[] = {
706 {"abs", math_abs},
707 {"acos", math_acos},
708 {"asin", math_asin},
709 {"atan", math_atan},
710 {"ceil", math_ceil},
711 {"cos", math_cos},
712 {"deg", math_deg},
713 {"exp", math_exp},
714 {"tointeger", math_toint},
715 {"floor", math_floor},
716 {"fmod", math_fmod},
717 {"ult", math_ult},
718 {"log", math_log},
719 {"max", math_max},
720 {"min", math_min},
721 {"modf", math_modf},
722 {"rad", math_rad},
723 {"sin", math_sin},
724 {"sqrt", math_sqrt},
725 {"tan", math_tan},
726 {"type", math_type},
727 #if defined(LUA_COMPAT_MATHLIB)
728 {"atan2", math_atan},
729 {"cosh", math_cosh},
730 {"sinh", math_sinh},
731 {"tanh", math_tanh},
732 {"pow", math_pow},
733 {"frexp", math_frexp},
734 {"ldexp", math_ldexp},
735 {"log10", math_log10},
736 #endif
737 /* placeholders */
738 {"random", NULL},
739 {"randomseed", NULL},
740 {"pi", NULL},
741 {"huge", NULL},
742 {"maxinteger", NULL},
743 {"mininteger", NULL},
744 {NULL, NULL}
745 };
746
747
748 /*
749 ** Open math library
750 */
luaopen_math(lua_State * L)751 LUAMOD_API int luaopen_math (lua_State *L) {
752 luaL_newlib(L, mathlib);
753 lua_pushnumber(L, PI);
754 lua_setfield(L, -2, "pi");
755 lua_pushnumber(L, (lua_Number)HUGE_VAL);
756 lua_setfield(L, -2, "huge");
757 lua_pushinteger(L, LUA_MAXINTEGER);
758 lua_setfield(L, -2, "maxinteger");
759 lua_pushinteger(L, LUA_MININTEGER);
760 lua_setfield(L, -2, "mininteger");
761 setrandfunc(L);
762 return 1;
763 }
764
765