| … | |
… | |
| 55 | #endif |
55 | #endif |
| 56 | |
56 | |
| 57 | // use C0X decltype for auto declarations until ISO C++ sanctifies them (if ever) |
57 | // use C0X decltype for auto declarations until ISO C++ sanctifies them (if ever) |
| 58 | #define auto(var,expr) decltype(expr) var = (expr) |
58 | #define auto(var,expr) decltype(expr) var = (expr) |
| 59 | |
59 | |
| 60 | // could use the sizeof (arr) /( sizeof (arr [0]) here, but C++ is |
60 | #if cplusplus_does_not_suck |
| 61 | // much more obfuscated... :) |
61 | // does not work for local types (http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2657.htm) |
| 62 | |
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| 63 | template<typename T, int N> |
62 | template<typename T, int N> |
| 64 | inline int array_length (const T (&arr)[N]) |
63 | static inline int array_length (const T (&arr)[N]) |
| 65 | { |
64 | { |
| 66 | return N; |
65 | return N; |
| 67 | } |
66 | } |
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|
67 | #else |
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68 | #define array_length(name) (sizeof (name) / sizeof (name [0])) |
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69 | #endif |
| 68 | |
70 | |
| 69 | // very ugly macro that basically declares and initialises a variable |
71 | // very ugly macro that basically declares and initialises a variable |
| 70 | // that is in scope for the next statement only |
72 | // that is in scope for the next statement only |
| 71 | // works only for stuff that can be assigned 0 and converts to false |
73 | // works only for stuff that can be assigned 0 and converts to false |
| 72 | // (note: works great for pointers) |
74 | // (note: works great for pointers) |
| … | |
… | |
| 121 | // div, with correct rounding (< 0.5 downwards, >=0.5 upwards) |
123 | // div, with correct rounding (< 0.5 downwards, >=0.5 upwards) |
| 122 | template<typename T> static inline T div (T val, T div) |
124 | template<typename T> static inline T div (T val, T div) |
| 123 | { |
125 | { |
| 124 | return expect_false (val < 0) ? - ((-val + (div - 1) / 2) / div) : (val + div / 2) / div; |
126 | return expect_false (val < 0) ? - ((-val + (div - 1) / 2) / div) : (val + div / 2) / div; |
| 125 | } |
127 | } |
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128 | |
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129 | template<> inline float div (float val, float div) { return val / div; } |
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130 | template<> inline double div (double val, double div) { return val / div; } |
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131 | |
| 126 | // div, round-up |
132 | // div, round-up |
| 127 | template<typename T> static inline T div_ru (T val, T div) |
133 | template<typename T> static inline T div_ru (T val, T div) |
| 128 | { |
134 | { |
| 129 | return expect_false (val < 0) ? - ((-val ) / div) : (val + div - 1) / div; |
135 | return expect_false (val < 0) ? - ((-val ) / div) : (val + div - 1) / div; |
| 130 | } |
136 | } |
| … | |
… | |
| 422 | void destroy (pointer p) |
428 | void destroy (pointer p) |
| 423 | { |
429 | { |
| 424 | p->~Tp (); |
430 | p->~Tp (); |
| 425 | } |
431 | } |
| 426 | }; |
432 | }; |
| 427 | |
|
|
| 428 | // P. L'Ecuyer, “Maximally Equidistributed Combined Tausworthe Generators”, Mathematics of Computation, 65, 213 (1996), 203–213. |
|
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| 429 | // http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme.ps |
|
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| 430 | // http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme2.ps |
|
|
| 431 | struct tausworthe_random_generator |
|
|
| 432 | { |
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| 433 | uint32_t state [4]; |
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| 434 | |
|
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| 435 | void operator =(const tausworthe_random_generator &src) |
|
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| 436 | { |
|
|
| 437 | state [0] = src.state [0]; |
|
|
| 438 | state [1] = src.state [1]; |
|
|
| 439 | state [2] = src.state [2]; |
|
|
| 440 | state [3] = src.state [3]; |
|
|
| 441 | } |
|
|
| 442 | |
|
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| 443 | void seed (uint32_t seed); |
|
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| 444 | uint32_t next (); |
|
|
| 445 | }; |
|
|
| 446 | |
|
|
| 447 | // Xorshift RNGs, George Marsaglia |
|
|
| 448 | // http://www.jstatsoft.org/v08/i14/paper |
|
|
| 449 | // this one is about 40% faster than the tausworthe one above (i.e. not much), |
|
|
| 450 | // despite the inlining, and has the issue of only creating 2**32-1 numbers. |
|
|
| 451 | // see also http://www.iro.umontreal.ca/~lecuyer/myftp/papers/xorshift.pdf |
|
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| 452 | struct xorshift_random_generator |
|
|
| 453 | { |
|
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| 454 | uint32_t x, y; |
|
|
| 455 | |
|
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| 456 | void operator =(const xorshift_random_generator &src) |
|
|
| 457 | { |
|
|
| 458 | x = src.x; |
|
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| 459 | y = src.y; |
|
|
| 460 | } |
|
|
| 461 | |
|
|
| 462 | void seed (uint32_t seed) |
|
|
| 463 | { |
|
|
| 464 | x = seed; |
|
|
| 465 | y = seed * 69069U; |
|
|
| 466 | } |
|
|
| 467 | |
|
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| 468 | uint32_t next () |
|
|
| 469 | { |
|
|
| 470 | uint32_t t = x ^ (x << 10); |
|
|
| 471 | x = y; |
|
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| 472 | y = y ^ (y >> 13) ^ t ^ (t >> 10); |
|
|
| 473 | return y; |
|
|
| 474 | } |
|
|
| 475 | }; |
|
|
| 476 | |
|
|
| 477 | template<class generator> |
|
|
| 478 | struct random_number_generator : generator |
|
|
| 479 | { |
|
|
| 480 | // uniform distribution, 0 .. max (0, num - 1) |
|
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| 481 | uint32_t operator ()(uint32_t num) |
|
|
| 482 | { |
|
|
| 483 | return !is_constant (num) ? get_range (num) // non-constant |
|
|
| 484 | : num & (num - 1) ? (this->next () * (uint64_t)num) >> 32U // constant, non-power-of-two |
|
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| 485 | : this->next () & (num - 1); // constant, power-of-two |
|
|
| 486 | } |
|
|
| 487 | |
|
|
| 488 | // return a number within the closed interval [min .. max] |
|
|
| 489 | int operator () (int r_min, int r_max) |
|
|
| 490 | { |
|
|
| 491 | return is_constant (r_min <= r_max) && r_min <= r_max |
|
|
| 492 | ? r_min + operator ()(r_max - r_min + 1) |
|
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| 493 | : get_range (r_min, r_max); |
|
|
| 494 | } |
|
|
| 495 | |
|
|
| 496 | // return a number within the closed interval [0..1] |
|
|
| 497 | double operator ()() |
|
|
| 498 | { |
|
|
| 499 | return this->next () / (double)0xFFFFFFFFU; |
|
|
| 500 | } |
|
|
| 501 | |
|
|
| 502 | protected: |
|
|
| 503 | uint32_t get_range (uint32_t r_max); |
|
|
| 504 | int get_range (int r_min, int r_max); |
|
|
| 505 | }; |
|
|
| 506 | |
|
|
| 507 | typedef random_number_generator<tausworthe_random_generator> rand_gen; |
|
|
| 508 | |
|
|
| 509 | extern rand_gen rndm, rmg_rndm; |
|
|
| 510 | |
433 | |
| 511 | INTERFACE_CLASS (attachable) |
434 | INTERFACE_CLASS (attachable) |
| 512 | struct refcnt_base |
435 | struct refcnt_base |
| 513 | { |
436 | { |
| 514 | typedef int refcnt_t; |
437 | typedef int refcnt_t; |
