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1034 lines
34 KiB
EmacsLisp
1034 lines
34 KiB
EmacsLisp
;;; calc-comb.el --- combinatoric functions for Calc
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;; Copyright (C) 1990, 1991, 1992, 1993, 2001, 2002, 2003, 2004,
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;; 2005, 2006, 2007 Free Software Foundation, Inc.
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;; Author: David Gillespie <daveg@synaptics.com>
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;; Maintainer: Jay Belanger <jay.p.belanger@gmail.com>
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;; This file is part of GNU Emacs.
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;; GNU Emacs is free software; you can redistribute it and/or modify
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;; it under the terms of the GNU General Public License as published by
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;; the Free Software Foundation; either version 3, or (at your option)
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;; any later version.
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;; GNU Emacs is distributed in the hope that it will be useful,
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;; but WITHOUT ANY WARRANTY; without even the implied warranty of
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;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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;; GNU General Public License for more details.
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;; You should have received a copy of the GNU General Public License
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;; along with GNU Emacs; see the file COPYING. If not, write to the
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;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
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;; Boston, MA 02110-1301, USA.
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;;; Commentary:
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;;; Code:
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;; This file is autoloaded from calc-ext.el.
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(require 'calc-ext)
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(require 'calc-macs)
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(defconst math-primes-table
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[2 3 5 7 11 13 17 19 23 29 31 37 41 43 47 53 59 61 67 71 73 79 83 89
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97 101 103 107 109 113 127 131 137 139 149 151 157 163 167 173 179 181
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191 193 197 199 211 223 227 229 233 239 241 251 257 263 269 271 277
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281 283 293 307 311 313 317 331 337 347 349 353 359 367 373 379 383
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389 397 401 409 419 421 431 433 439 443 449 457 461 463 467 479 487
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491 499 503 509 521 523 541 547 557 563 569 571 577 587 593 599 601
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607 613 617 619 631 641 643 647 653 659 661 673 677 683 691 701 709
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719 727 733 739 743 751 757 761 769 773 787 797 809 811 821 823 827
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829 839 853 857 859 863 877 881 883 887 907 911 919 929 937 941 947
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953 967 971 977 983 991 997 1009 1013 1019 1021 1031 1033 1039 1049
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1051 1061 1063 1069 1087 1091 1093 1097 1103 1109 1117 1123 1129 1151
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1153 1163 1171 1181 1187 1193 1201 1213 1217 1223 1229 1231 1237 1249
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1259 1277 1279 1283 1289 1291 1297 1301 1303 1307 1319 1321 1327 1361
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1367 1373 1381 1399 1409 1423 1427 1429 1433 1439 1447 1451 1453 1459
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1471 1481 1483 1487 1489 1493 1499 1511 1523 1531 1543 1549 1553 1559
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1567 1571 1579 1583 1597 1601 1607 1609 1613 1619 1621 1627 1637 1657
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1663 1667 1669 1693 1697 1699 1709 1721 1723 1733 1741 1747 1753 1759
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1777 1783 1787 1789 1801 1811 1823 1831 1847 1861 1867 1871 1873 1877
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1879 1889 1901 1907 1913 1931 1933 1949 1951 1973 1979 1987 1993 1997
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1999 2003 2011 2017 2027 2029 2039 2053 2063 2069 2081 2083 2087 2089
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2099 2111 2113 2129 2131 2137 2141 2143 2153 2161 2179 2203 2207 2213
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2221 2237 2239 2243 2251 2267 2269 2273 2281 2287 2293 2297 2309 2311
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2333 2339 2341 2347 2351 2357 2371 2377 2381 2383 2389 2393 2399 2411
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2417 2423 2437 2441 2447 2459 2467 2473 2477 2503 2521 2531 2539 2543
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2549 2551 2557 2579 2591 2593 2609 2617 2621 2633 2647 2657 2659 2663
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2671 2677 2683 2687 2689 2693 2699 2707 2711 2713 2719 2729 2731 2741
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2749 2753 2767 2777 2789 2791 2797 2801 2803 2819 2833 2837 2843 2851
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2857 2861 2879 2887 2897 2903 2909 2917 2927 2939 2953 2957 2963 2969
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2971 2999 3001 3011 3019 3023 3037 3041 3049 3061 3067 3079 3083 3089
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3109 3119 3121 3137 3163 3167 3169 3181 3187 3191 3203 3209 3217 3221
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3229 3251 3253 3257 3259 3271 3299 3301 3307 3313 3319 3323 3329 3331
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3343 3347 3359 3361 3371 3373 3389 3391 3407 3413 3433 3449 3457 3461
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3463 3467 3469 3491 3499 3511 3517 3527 3529 3533 3539 3541 3547 3557
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3559 3571 3581 3583 3593 3607 3613 3617 3623 3631 3637 3643 3659 3671
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3673 3677 3691 3697 3701 3709 3719 3727 3733 3739 3761 3767 3769 3779
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3793 3797 3803 3821 3823 3833 3847 3851 3853 3863 3877 3881 3889 3907
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3911 3917 3919 3923 3929 3931 3943 3947 3967 3989 4001 4003 4007 4013
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4019 4021 4027 4049 4051 4057 4073 4079 4091 4093 4099 4111 4127 4129
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4133 4139 4153 4157 4159 4177 4201 4211 4217 4219 4229 4231 4241 4243
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4253 4259 4261 4271 4273 4283 4289 4297 4327 4337 4339 4349 4357 4363
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4373 4391 4397 4409 4421 4423 4441 4447 4451 4457 4463 4481 4483 4493
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4507 4513 4517 4519 4523 4547 4549 4561 4567 4583 4591 4597 4603 4621
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4637 4639 4643 4649 4651 4657 4663 4673 4679 4691 4703 4721 4723 4729
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4733 4751 4759 4783 4787 4789 4793 4799 4801 4813 4817 4831 4861 4871
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4877 4889 4903 4909 4919 4931 4933 4937 4943 4951 4957 4967 4969 4973
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4987 4993 4999 5003])
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;; The variable math-prime-factors-finished is set by calcFunc-prfac to
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;; indicate whether factoring is complete, and used by calcFunc-factors,
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;; calcFunc-totient and calcFunc-moebius.
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(defvar math-prime-factors-finished)
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;;; Combinatorics
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(defun calc-gcd (arg)
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(interactive "P")
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(calc-slow-wrapper
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(calc-binary-op "gcd" 'calcFunc-gcd arg)))
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(defun calc-lcm (arg)
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(interactive "P")
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(calc-slow-wrapper
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(calc-binary-op "lcm" 'calcFunc-lcm arg)))
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(defun calc-extended-gcd ()
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(interactive)
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(calc-slow-wrapper
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(calc-enter-result 2 "egcd" (cons 'calcFunc-egcd (calc-top-list-n 2)))))
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(defun calc-factorial (arg)
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(interactive "P")
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(calc-slow-wrapper
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(calc-unary-op "fact" 'calcFunc-fact arg)))
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(defun calc-gamma (arg)
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(interactive "P")
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(calc-slow-wrapper
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(calc-unary-op "gmma" 'calcFunc-gamma arg)))
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(defun calc-double-factorial (arg)
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(interactive "P")
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(calc-slow-wrapper
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(calc-unary-op "dfac" 'calcFunc-dfact arg)))
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(defun calc-choose (arg)
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(interactive "P")
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(calc-slow-wrapper
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(if (calc-is-hyperbolic)
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(calc-binary-op "perm" 'calcFunc-perm arg)
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(calc-binary-op "chos" 'calcFunc-choose arg))))
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(defun calc-perm (arg)
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(interactive "P")
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(calc-hyperbolic-func)
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(calc-choose arg))
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(defvar calc-last-random-limit '(float 1 0))
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(defun calc-random (n)
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(interactive "P")
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(calc-slow-wrapper
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(if n
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(calc-enter-result 0 "rand" (list 'calcFunc-random
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(calc-get-random-limit
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(prefix-numeric-value n))))
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(calc-enter-result 1 "rand" (list 'calcFunc-random
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(calc-get-random-limit
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(calc-top-n 1)))))))
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(defun calc-get-random-limit (val)
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(if (eq val 0)
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calc-last-random-limit
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(setq calc-last-random-limit val)))
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(defun calc-rrandom ()
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(interactive)
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(calc-slow-wrapper
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(setq calc-last-random-limit '(float 1 0))
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(calc-enter-result 0 "rand" (list 'calcFunc-random '(float 1 0)))))
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(defun calc-random-again (arg)
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(interactive "p")
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(calc-slow-wrapper
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(while (>= (setq arg (1- arg)) 0)
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(calc-enter-result 0 "rand" (list 'calcFunc-random
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calc-last-random-limit)))))
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(defun calc-shuffle (n)
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(interactive "P")
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(calc-slow-wrapper
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(if n
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(calc-enter-result 1 "shuf" (list 'calcFunc-shuffle
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(prefix-numeric-value n)
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(calc-get-random-limit
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(calc-top-n 1))))
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(calc-enter-result 2 "shuf" (list 'calcFunc-shuffle
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(calc-top-n 1)
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(calc-get-random-limit
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(calc-top-n 2)))))))
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(defun calc-report-prime-test (res)
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(cond ((eq (car res) t)
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(calc-record-message "prim" "Prime (guaranteed)"))
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((eq (car res) nil)
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(if (cdr res)
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(if (eq (nth 1 res) 'unknown)
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(calc-record-message
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"prim" "Non-prime (factors unknown)")
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(calc-record-message
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"prim" "Non-prime (%s is a factor)"
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(math-format-number (nth 1 res))))
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(calc-record-message "prim" "Non-prime")))
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(t
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(calc-record-message
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"prim" "Probably prime (%d iters; %s%% chance of error)"
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(nth 1 res)
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(let ((calc-float-format '(fix 2)))
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(math-format-number (nth 2 res)))))))
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(defun calc-prime-test (iters)
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(interactive "p")
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(calc-slow-wrapper
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(let* ((n (calc-top-n 1))
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(res (math-prime-test n iters)))
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(calc-report-prime-test res))))
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(defvar calc-verbose-nextprime nil)
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(defun calc-next-prime (iters)
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(interactive "p")
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(calc-slow-wrapper
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(let ((calc-verbose-nextprime t))
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(if (calc-is-inverse)
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(calc-enter-result 1 "prvp" (list 'calcFunc-prevprime
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(calc-top-n 1) (math-abs iters)))
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(calc-enter-result 1 "nxtp" (list 'calcFunc-nextprime
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(calc-top-n 1) (math-abs iters)))))))
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(defun calc-prev-prime (iters)
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(interactive "p")
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(calc-invert-func)
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(calc-next-prime iters))
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(defun calc-prime-factors (iters)
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(interactive "p")
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(calc-slow-wrapper
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(let ((res (calcFunc-prfac (calc-top-n 1))))
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(if (not math-prime-factors-finished)
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(calc-record-message "pfac" "Warning: May not be fully factored"))
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(calc-enter-result 1 "pfac" res))))
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(defun calc-totient (arg)
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(interactive "P")
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(calc-slow-wrapper
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(calc-unary-op "phi" 'calcFunc-totient arg)))
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(defun calc-moebius (arg)
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(interactive "P")
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(calc-slow-wrapper
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(calc-unary-op "mu" 'calcFunc-moebius arg)))
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(defun calcFunc-gcd (a b)
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(if (Math-messy-integerp a)
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(setq a (math-trunc a)))
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(if (Math-messy-integerp b)
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(setq b (math-trunc b)))
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(cond ((and (Math-integerp a) (Math-integerp b))
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(math-gcd a b))
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((Math-looks-negp a)
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(calcFunc-gcd (math-neg a) b))
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((Math-looks-negp b)
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(calcFunc-gcd a (math-neg b)))
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((Math-zerop a) b)
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((Math-zerop b) a)
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((and (Math-ratp a)
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(Math-ratp b))
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(math-make-frac (math-gcd (if (eq (car-safe a) 'frac) (nth 1 a) a)
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(if (eq (car-safe b) 'frac) (nth 1 b) b))
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(calcFunc-lcm
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(if (eq (car-safe a) 'frac) (nth 2 a) 1)
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(if (eq (car-safe b) 'frac) (nth 2 b) 1))))
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((not (Math-integerp a))
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(calc-record-why 'integerp a)
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(list 'calcFunc-gcd a b))
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(t
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(calc-record-why 'integerp b)
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(list 'calcFunc-gcd a b))))
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(defun calcFunc-lcm (a b)
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(let ((g (calcFunc-gcd a b)))
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(if (Math-numberp g)
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(math-div (math-mul a b) g)
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(list 'calcFunc-lcm a b))))
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(defun calcFunc-egcd (a b) ; Knuth section 4.5.2
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(cond
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((not (Math-integerp a))
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(if (Math-messy-integerp a)
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(calcFunc-egcd (math-trunc a) b)
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(calc-record-why 'integerp a)
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(list 'calcFunc-egcd a b)))
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((not (Math-integerp b))
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(if (Math-messy-integerp b)
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(calcFunc-egcd a (math-trunc b))
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(calc-record-why 'integerp b)
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(list 'calcFunc-egcd a b)))
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(t
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(let ((u1 1) (u2 0) (u3 a)
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(v1 0) (v2 1) (v3 b)
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t1 t2 q)
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(while (not (eq v3 0))
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(setq q (math-idivmod u3 v3)
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t1 (math-sub u1 (math-mul v1 (car q)))
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t2 (math-sub u2 (math-mul v2 (car q)))
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u1 v1 u2 v2 u3 v3
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v1 t1 v2 t2 v3 (cdr q)))
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(list 'vec u3 u1 u2)))))
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;;; Factorial and related functions.
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(defconst math-small-factorial-table
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(vector 1 1 2 6 24 120 720 5040 40320 362880 3628800 39916800
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(math-read-number-simple "479001600")
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(math-read-number-simple "6227020800")
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(math-read-number-simple "87178291200")
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(math-read-number-simple "1307674368000")
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(math-read-number-simple "20922789888000")
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(math-read-number-simple "355687428096000")
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(math-read-number-simple "6402373705728000")
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(math-read-number-simple "121645100408832000")
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(math-read-number-simple "2432902008176640000")))
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(defun calcFunc-fact (n) ; [I I] [F F] [Public]
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(let (temp)
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(cond ((Math-integer-negp n)
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(if calc-infinite-mode
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'(var uinf var-uinf)
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(math-reject-arg n 'range)))
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((integerp n)
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(if (<= n 20)
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(aref math-small-factorial-table n)
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(math-factorial-iter (1- n) 2 1)))
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((and (math-messy-integerp n)
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(Math-lessp n 100))
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(math-inexact-result)
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(setq temp (math-trunc n))
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(if (>= temp 0)
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(if (<= temp 20)
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(math-float (calcFunc-fact temp))
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(math-with-extra-prec 1
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(math-factorial-iter (1- temp) 2 '(float 1 0))))
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(math-reject-arg n 'range)))
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((math-numberp n)
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(let* ((q (math-quarter-integer n))
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(tn (and q (Math-lessp n 1000) (Math-lessp -1000 n)
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(1+ (math-floor n)))))
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(cond ((and tn (= q 2)
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(or calc-symbolic-mode (< (math-abs tn) 20)))
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(let ((q (if (< tn 0)
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(math-div
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(math-pow -2 (- tn))
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(math-double-factorial-iter (* -2 tn) 3 1 2))
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(math-div
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(math-double-factorial-iter (* 2 tn) 3 1 2)
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(math-pow 2 tn)))))
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(math-mul q (if calc-symbolic-mode
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(list 'calcFunc-sqrt '(var pi var-pi))
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(math-sqrt-pi)))))
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((and tn (>= tn 0) (< tn 20)
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(memq q '(1 3)))
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(math-inexact-result)
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(math-div
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(math-mul (math-double-factorial-iter (* 4 tn) q 1 4)
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(if (= q 1) (math-gamma-1q) (math-gamma-3q)))
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(math-pow 4 tn)))
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(t
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(math-inexact-result)
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(math-with-extra-prec 3
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(math-gammap1-raw (math-float n)))))))
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((equal n '(var inf var-inf)) n)
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(t (calc-record-why 'numberp n)
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(list 'calcFunc-fact n)))))
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(math-defcache math-gamma-1q nil
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(math-with-extra-prec 3
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(math-gammap1-raw '(float -75 -2))))
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(math-defcache math-gamma-3q nil
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(math-with-extra-prec 3
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(math-gammap1-raw '(float -25 -2))))
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(defun math-factorial-iter (count n f)
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(if (= (% n 5) 1)
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(math-working (format "factorial(%d)" (1- n)) f))
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(if (> count 0)
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(math-factorial-iter (1- count) (1+ n) (math-mul n f))
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f))
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(defun calcFunc-dfact (n) ; [I I] [F F] [Public]
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(cond ((Math-integer-negp n)
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(if (math-oddp n)
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(if (eq n -1)
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1
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(math-div (if (eq (math-mod n 4) 3) 1 -1)
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(calcFunc-dfact (math-sub -2 n))))
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(list 'calcFunc-dfact n)))
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((Math-zerop n) 1)
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((integerp n) (math-double-factorial-iter n (+ 2 (% n 2)) 1 2))
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((math-messy-integerp n)
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(let ((temp (math-trunc n)))
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(math-inexact-result)
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(if (natnump temp)
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(if (Math-lessp temp 200)
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(math-with-extra-prec 1
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(math-double-factorial-iter temp (+ 2 (% temp 2))
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'(float 1 0) 2))
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(let* ((half (math-div2 temp))
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(even (math-mul (math-pow 2 half)
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(calcFunc-fact (math-float half)))))
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(if (math-evenp temp)
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even
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(math-div (calcFunc-fact n) even))))
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(list 'calcFunc-dfact n))))
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((equal n '(var inf var-inf)) n)
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(t (calc-record-why 'natnump n)
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(list 'calcFunc-dfact n))))
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(defun math-double-factorial-iter (max n f step)
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(if (< (% n 12) step)
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(math-working (format "dfact(%d)" (- n step)) f))
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(if (<= n max)
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(math-double-factorial-iter max (+ n step) (math-mul n f) step)
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f))
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(defun calcFunc-perm (n m) ; [I I I] [F F F] [Public]
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(cond ((and (integerp n) (integerp m) (<= m n) (>= m 0))
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(math-factorial-iter m (1+ (- n m)) 1))
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((or (not (math-num-integerp n))
|
|
(and (math-messy-integerp n) (Math-lessp 100 n))
|
|
(not (math-num-integerp m))
|
|
(and (math-messy-integerp m) (Math-lessp 100 m)))
|
|
(or (math-realp n) (equal n '(var inf var-inf))
|
|
(math-reject-arg n 'realp))
|
|
(or (math-realp m) (equal m '(var inf var-inf))
|
|
(math-reject-arg m 'realp))
|
|
(and (math-num-integerp n) (math-negp n) (math-reject-arg n 'range))
|
|
(and (math-num-integerp m) (math-negp m) (math-reject-arg m 'range))
|
|
(math-div (calcFunc-fact n) (calcFunc-fact (math-sub n m))))
|
|
(t
|
|
(let ((tn (math-trunc n))
|
|
(tm (math-trunc m)))
|
|
(math-inexact-result)
|
|
(or (integerp tn) (math-reject-arg tn 'fixnump))
|
|
(or (integerp tm) (math-reject-arg tm 'fixnump))
|
|
(or (and (<= tm tn) (>= tm 0)) (math-reject-arg tm 'range))
|
|
(math-with-extra-prec 1
|
|
(math-factorial-iter tm (1+ (- tn tm)) '(float 1 0)))))))
|
|
|
|
(defun calcFunc-choose (n m) ; [I I I] [F F F] [Public]
|
|
(cond ((and (integerp n) (integerp m) (<= m n) (>= m 0))
|
|
(if (> m (/ n 2))
|
|
(math-choose-iter (- n m) n 1 1)
|
|
(math-choose-iter m n 1 1)))
|
|
((not (math-realp n))
|
|
(math-reject-arg n 'realp))
|
|
((not (math-realp m))
|
|
(math-reject-arg m 'realp))
|
|
((not (math-num-integerp m))
|
|
(if (and (math-num-integerp n) (math-negp n))
|
|
(list 'calcFunc-choose n m)
|
|
(math-div (calcFunc-fact (math-float n))
|
|
(math-mul (calcFunc-fact m)
|
|
(calcFunc-fact (math-sub n m))))))
|
|
((math-negp m) 0)
|
|
((math-negp n)
|
|
(let ((val (calcFunc-choose (math-add (math-add n m) -1) m)))
|
|
(if (math-evenp (math-trunc m))
|
|
val
|
|
(math-neg val))))
|
|
((and (math-num-integerp n)
|
|
(Math-lessp n m))
|
|
0)
|
|
(t
|
|
(math-inexact-result)
|
|
(let ((tm (math-trunc m)))
|
|
(or (integerp tm) (math-reject-arg tm 'fixnump))
|
|
(if (> tm 100)
|
|
(math-div (calcFunc-fact (math-float n))
|
|
(math-mul (calcFunc-fact (math-float m))
|
|
(calcFunc-fact (math-float
|
|
(math-sub n m)))))
|
|
(math-with-extra-prec 1
|
|
(math-choose-float-iter tm n 1 1)))))))
|
|
|
|
(defun math-choose-iter (m n i c)
|
|
(if (and (= (% i 5) 1) (> i 5))
|
|
(math-working (format "choose(%d)" (1- i)) c))
|
|
(if (<= i m)
|
|
(math-choose-iter m (1- n) (1+ i)
|
|
(math-quotient (math-mul c n) i))
|
|
c))
|
|
|
|
(defun math-choose-float-iter (count n i c)
|
|
(if (= (% i 5) 1)
|
|
(math-working (format "choose(%d)" (1- i)) c))
|
|
(if (> count 0)
|
|
(math-choose-float-iter (1- count) (math-sub n 1) (1+ i)
|
|
(math-div (math-mul c n) i))
|
|
c))
|
|
|
|
|
|
;;; Stirling numbers.
|
|
|
|
(defun calcFunc-stir1 (n m)
|
|
(math-stirling-number n m 1))
|
|
|
|
(defun calcFunc-stir2 (n m)
|
|
(math-stirling-number n m 0))
|
|
|
|
(defvar math-stirling-cache (vector [[1]] [[1]]))
|
|
|
|
;; The variable math-stirling-local-cache is local to
|
|
;; math-stirling-number, but is used by math-stirling-1
|
|
;; and math-stirling-2, which are called by math-stirling-number.
|
|
(defvar math-stirling-local-cache)
|
|
|
|
(defun math-stirling-number (n m k)
|
|
(or (math-num-natnump n) (math-reject-arg n 'natnump))
|
|
(or (math-num-natnump m) (math-reject-arg m 'natnump))
|
|
(if (consp n) (setq n (math-trunc n)))
|
|
(or (integerp n) (math-reject-arg n 'fixnump))
|
|
(if (consp m) (setq m (math-trunc m)))
|
|
(or (integerp m) (math-reject-arg m 'fixnump))
|
|
(if (< n m)
|
|
0
|
|
(let ((math-stirling-local-cache (aref math-stirling-cache k)))
|
|
(while (<= (length math-stirling-local-cache) n)
|
|
(let ((i (1- (length math-stirling-local-cache)))
|
|
row)
|
|
(setq math-stirling-local-cache
|
|
(vconcat math-stirling-local-cache
|
|
(make-vector (length math-stirling-local-cache) nil)))
|
|
(aset math-stirling-cache k math-stirling-local-cache)
|
|
(while (< (setq i (1+ i)) (length math-stirling-local-cache))
|
|
(aset math-stirling-local-cache i (setq row (make-vector (1+ i) nil)))
|
|
(aset row 0 0)
|
|
(aset row i 1))))
|
|
(if (= k 1)
|
|
(math-stirling-1 n m)
|
|
(math-stirling-2 n m)))))
|
|
|
|
(defun math-stirling-1 (n m)
|
|
(or (aref (aref math-stirling-local-cache n) m)
|
|
(aset (aref math-stirling-local-cache n) m
|
|
(math-add (math-stirling-1 (1- n) (1- m))
|
|
(math-mul (- 1 n) (math-stirling-1 (1- n) m))))))
|
|
|
|
(defun math-stirling-2 (n m)
|
|
(or (aref (aref math-stirling-local-cache n) m)
|
|
(aset (aref math-stirling-local-cache n) m
|
|
(math-add (math-stirling-2 (1- n) (1- m))
|
|
(math-mul m (math-stirling-2 (1- n) m))))))
|
|
|
|
(defvar math-random-table nil)
|
|
(defvar math-last-RandSeed nil)
|
|
(defvar math-random-ptr1 nil)
|
|
(defvar math-random-ptr2 nil)
|
|
(defvar math-random-shift nil)
|
|
|
|
;;; Produce a random 10-bit integer, with (random) if no seed provided,
|
|
;;; or else with Numerical Recipes algorithm ran3 / Knuth 3.2.2-A.
|
|
|
|
(defvar var-RandSeed)
|
|
(defvar math-random-cache nil)
|
|
(defvar math-gaussian-cache nil)
|
|
|
|
(defun math-init-random-base ()
|
|
(if (and (boundp 'var-RandSeed) var-RandSeed)
|
|
(if (eq (car-safe var-RandSeed) 'vec)
|
|
nil
|
|
(if (Math-integerp var-RandSeed)
|
|
(let* ((seed (math-sub 161803 var-RandSeed))
|
|
(mj (1+ (math-mod seed 1000000)))
|
|
(mk (1+ (math-mod (math-quotient seed 1000000)
|
|
1000000)))
|
|
(i 0))
|
|
(setq math-random-table (cons 'vec (make-list 55 mj)))
|
|
(while (<= (setq i (1+ i)) 54)
|
|
(let* ((ii (% (* i 21) 55))
|
|
(p (nthcdr ii math-random-table)))
|
|
(setcar p mk)
|
|
(setq mk (- mj mk)
|
|
mj (car p)))))
|
|
(math-reject-arg var-RandSeed "*RandSeed must be an integer"))
|
|
(setq var-RandSeed (list 'vec var-RandSeed)
|
|
math-random-ptr1 math-random-table
|
|
math-random-cache nil
|
|
math-random-ptr2 (nthcdr 31 math-random-table))
|
|
(let ((i 200))
|
|
(while (> (setq i (1- i)) 0)
|
|
(math-random-base))))
|
|
(random t)
|
|
(setq var-RandSeed nil
|
|
math-random-cache nil
|
|
math-random-shift -4) ; assume RAND_MAX >= 16383
|
|
;; This exercises the random number generator and also helps
|
|
;; deduce a better value for RAND_MAX.
|
|
(let ((i 0))
|
|
(while (< (setq i (1+ i)) 30)
|
|
(if (> (lsh (math-abs (random)) math-random-shift) 4095)
|
|
(setq math-random-shift (1- math-random-shift))))))
|
|
(setq math-last-RandSeed var-RandSeed
|
|
math-gaussian-cache nil))
|
|
|
|
(defun math-random-base ()
|
|
(if var-RandSeed
|
|
(progn
|
|
(setq math-random-ptr1 (or (cdr math-random-ptr1)
|
|
(cdr math-random-table))
|
|
math-random-ptr2 (or (cdr math-random-ptr2)
|
|
(cdr math-random-table)))
|
|
(logand (lsh (setcar math-random-ptr1
|
|
(logand (- (car math-random-ptr1)
|
|
(car math-random-ptr2)) 524287))
|
|
-6) 1023))
|
|
(logand (lsh (random) math-random-shift) 1023)))
|
|
|
|
|
|
;;; Produce a random digit in the range 0..999.
|
|
;;; Avoid various pitfalls that may lurk in the built-in (random) function!
|
|
;;; Shuffling algorithm from Numerical Recipes, section 7.1.
|
|
(defvar math-random-last)
|
|
(defun math-random-three-digit-number ()
|
|
"Return a random three digit number."
|
|
(let (i)
|
|
(or (and (boundp 'var-RandSeed) (eq var-RandSeed math-last-RandSeed))
|
|
(math-init-random-base))
|
|
(or math-random-cache
|
|
(progn
|
|
(setq math-random-last (math-random-base)
|
|
math-random-cache (make-vector 13 nil)
|
|
i -1)
|
|
(while (< (setq i (1+ i)) 13)
|
|
(aset math-random-cache i (math-random-base)))))
|
|
(while (progn
|
|
(setq i (/ math-random-last 79) ; 0 <= i < 13
|
|
math-random-last (aref math-random-cache i))
|
|
(aset math-random-cache i (math-random-base))
|
|
(>= math-random-last 1000)))
|
|
math-random-last))
|
|
|
|
;;; Produce an N-digit random integer.
|
|
(defun math-random-digits (n)
|
|
"Produce a random N digit integer."
|
|
(let* ((slop (% (- 3 (% n 3)) 3))
|
|
(i (/ (+ n slop) 3))
|
|
(rnum 0))
|
|
(while (> i 0)
|
|
(setq rnum
|
|
(math-add
|
|
(math-random-three-digit-number)
|
|
(math-mul rnum 1000)))
|
|
(setq i (1- i)))
|
|
(math-normalize (math-scale-right rnum slop))))
|
|
|
|
;;; Produce a uniformly-distributed random float 0 <= N < 1.
|
|
(defun math-random-float ()
|
|
(math-make-float (math-random-digits calc-internal-prec)
|
|
(- calc-internal-prec)))
|
|
|
|
;;; Produce a Gaussian-distributed random float with mean=0, sigma=1.
|
|
(defun math-gaussian-float ()
|
|
(math-with-extra-prec 2
|
|
(if (and math-gaussian-cache
|
|
(= (car math-gaussian-cache) calc-internal-prec))
|
|
(prog1
|
|
(cdr math-gaussian-cache)
|
|
(setq math-gaussian-cache nil))
|
|
(let* ((v1 (math-add (math-mul (math-random-float) 2) -1))
|
|
(v2 (math-add (math-mul (math-random-float) 2) -1))
|
|
(r (math-add (math-sqr v1) (math-sqr v2))))
|
|
(while (or (not (Math-lessp r 1)) (math-zerop r))
|
|
(setq v1 (math-add (math-mul (math-random-float) 2) -1)
|
|
v2 (math-add (math-mul (math-random-float) 2) -1)
|
|
r (math-add (math-sqr v1) (math-sqr v2))))
|
|
(let ((fac (math-sqrt (math-mul (math-div (calcFunc-ln r) r) -2))))
|
|
(setq math-gaussian-cache (cons calc-internal-prec
|
|
(math-mul v1 fac)))
|
|
(math-mul v2 fac))))))
|
|
|
|
;;; Produce a random integer or real 0 <= N < MAX.
|
|
(defun calcFunc-random (max)
|
|
(cond ((Math-zerop max)
|
|
(math-gaussian-float))
|
|
((Math-integerp max)
|
|
(let* ((digs (math-numdigs max))
|
|
(r (math-random-digits (+ digs 3))))
|
|
(math-mod r max)))
|
|
((Math-realp max)
|
|
(math-mul (math-random-float) max))
|
|
((and (eq (car max) 'intv) (math-constp max)
|
|
(Math-lessp (nth 2 max) (nth 3 max)))
|
|
(if (math-floatp max)
|
|
(let ((val (math-add (math-mul (math-random-float)
|
|
(math-sub (nth 3 max) (nth 2 max)))
|
|
(nth 2 max))))
|
|
(if (or (and (memq (nth 1 max) '(0 1)) ; almost not worth
|
|
(Math-equal val (nth 2 max))) ; checking!
|
|
(and (memq (nth 1 max) '(0 2))
|
|
(Math-equal val (nth 3 max))))
|
|
(calcFunc-random max)
|
|
val))
|
|
(let ((lo (if (memq (nth 1 max) '(0 1))
|
|
(math-add (nth 2 max) 1) (nth 2 max)))
|
|
(hi (if (memq (nth 1 max) '(1 3))
|
|
(math-add (nth 3 max) 1) (nth 3 max))))
|
|
(if (Math-lessp lo hi)
|
|
(math-add (calcFunc-random (math-sub hi lo)) lo)
|
|
(math-reject-arg max "*Empty interval")))))
|
|
((eq (car max) 'vec)
|
|
(if (cdr max)
|
|
(nth (1+ (calcFunc-random (1- (length max)))) max)
|
|
(math-reject-arg max "*Empty list")))
|
|
((and (eq (car max) 'sdev) (math-constp max) (Math-realp (nth 1 max)))
|
|
(math-add (math-mul (math-gaussian-float) (nth 2 max)) (nth 1 max)))
|
|
(t (math-reject-arg max 'realp))))
|
|
|
|
;;; Choose N objects at random from the set MAX without duplicates.
|
|
(defun calcFunc-shuffle (n &optional max)
|
|
(or max (setq max n n -1))
|
|
(or (and (Math-num-integerp n)
|
|
(or (natnump (setq n (math-trunc n))) (eq n -1)))
|
|
(math-reject-arg n 'integerp))
|
|
(cond ((or (math-zerop max)
|
|
(math-floatp max)
|
|
(eq (car-safe max) 'sdev))
|
|
(if (< n 0)
|
|
(math-reject-arg n 'natnump)
|
|
(math-simple-shuffle n max)))
|
|
((and (<= n 1) (>= n 0))
|
|
(math-simple-shuffle n max))
|
|
((and (eq (car-safe max) 'intv) (math-constp max))
|
|
(let ((num (math-add (math-sub (nth 3 max) (nth 2 max))
|
|
(cdr (assq (nth 1 max)
|
|
'((0 . -1) (1 . 0)
|
|
(2 . 0) (3 . 1))))))
|
|
(min (math-add (nth 2 max) (if (memq (nth 1 max) '(0 1))
|
|
1 0))))
|
|
(if (< n 0) (setq n num))
|
|
(or (math-posp num) (math-reject-arg max 'range))
|
|
(and (Math-lessp num n) (math-reject-arg n 'range))
|
|
(if (Math-lessp n (math-quotient num 3))
|
|
(math-simple-shuffle n max)
|
|
(if (> (* n 4) (* num 3))
|
|
(math-add (math-sub min 1)
|
|
(math-shuffle-list n num (calcFunc-index num)))
|
|
(let ((tot 0)
|
|
(m 0)
|
|
(vec nil))
|
|
(while (< m n)
|
|
(if (< (calcFunc-random (- num tot)) (- n m))
|
|
(setq vec (cons (math-add min tot) vec)
|
|
m (1+ m)))
|
|
(setq tot (1+ tot)))
|
|
(math-shuffle-list n n (cons 'vec vec)))))))
|
|
((eq (car-safe max) 'vec)
|
|
(let ((size (1- (length max))))
|
|
(if (< n 0) (setq n size))
|
|
(if (and (> n (/ size 2)) (<= n size))
|
|
(math-shuffle-list n size (copy-sequence max))
|
|
(let* ((vals (calcFunc-shuffle
|
|
n (list 'intv 3 1 (1- (length max)))))
|
|
(p vals))
|
|
(while (setq p (cdr p))
|
|
(setcar p (nth (car p) max)))
|
|
vals))))
|
|
((math-integerp max)
|
|
(if (math-posp max)
|
|
(calcFunc-shuffle n (list 'intv 2 0 max))
|
|
(calcFunc-shuffle n (list 'intv 1 max 0))))
|
|
(t (math-reject-arg max 'realp))))
|
|
|
|
(defun math-simple-shuffle (n max)
|
|
(let ((vec nil)
|
|
val)
|
|
(while (>= (setq n (1- n)) 0)
|
|
(while (math-member (setq val (calcFunc-random max)) vec))
|
|
(setq vec (cons val vec)))
|
|
(cons 'vec vec)))
|
|
|
|
(defun math-shuffle-list (n size vec)
|
|
(let ((j size)
|
|
k temp
|
|
(p vec))
|
|
(while (cdr (setq p (cdr p)))
|
|
(setq k (calcFunc-random j)
|
|
j (1- j)
|
|
temp (nth k p))
|
|
(setcar (nthcdr k p) (car p))
|
|
(setcar p temp))
|
|
(cons 'vec (nthcdr (- size n -1) vec))))
|
|
|
|
(defun math-member (x list)
|
|
(while (and list (not (equal x (car list))))
|
|
(setq list (cdr list)))
|
|
list)
|
|
|
|
|
|
;;; Check if the integer N is prime. [X I]
|
|
;;; Return (nil) if non-prime,
|
|
;;; (nil N) if non-prime with known factor N,
|
|
;;; (nil unknown) if non-prime with no known factors,
|
|
;;; (t) if prime,
|
|
;;; (maybe N P) if probably prime (after N iters with probability P%)
|
|
(defvar math-prime-test-cache '(-1))
|
|
|
|
(defvar math-prime-test-cache-k)
|
|
(defvar math-prime-test-cache-q)
|
|
(defvar math-prime-test-cache-nm1)
|
|
|
|
(defun math-prime-test (n iters)
|
|
(if (and (Math-vectorp n) (cdr n))
|
|
(setq n (nth (1- (length n)) n)))
|
|
(if (Math-messy-integerp n)
|
|
(setq n (math-trunc n)))
|
|
(let ((res))
|
|
(while (> iters 0)
|
|
(setq res
|
|
(cond ((and (integerp n) (<= n 5003))
|
|
(list (= (math-next-small-prime n) n)))
|
|
((not (Math-integerp n))
|
|
(error "Argument must be an integer"))
|
|
((Math-integer-negp n)
|
|
'(nil))
|
|
((Math-natnum-lessp n 8000000)
|
|
(setq n (math-fixnum n))
|
|
(let ((i -1) v)
|
|
(while (and (> (% n (setq v (aref math-primes-table
|
|
(setq i (1+ i)))))
|
|
0)
|
|
(< (* v v) n)))
|
|
(if (= (% n v) 0)
|
|
(list nil v)
|
|
'(t))))
|
|
((not (equal n (car math-prime-test-cache)))
|
|
(cond ((= (% (nth 1 n) 2) 0) '(nil 2))
|
|
((= (% (nth 1 n) 5) 0) '(nil 5))
|
|
(t (let ((q n) (sum 0))
|
|
(while (not (eq q 0))
|
|
(setq sum (%
|
|
(+
|
|
sum
|
|
(calcFunc-mod
|
|
q 1000000))
|
|
111111))
|
|
(setq q
|
|
(math-quotient
|
|
q 1000000)))
|
|
(cond ((= (% sum 3) 0) '(nil 3))
|
|
((= (% sum 7) 0) '(nil 7))
|
|
((= (% sum 11) 0) '(nil 11))
|
|
((= (% sum 13) 0) '(nil 13))
|
|
((= (% sum 37) 0) '(nil 37))
|
|
(t
|
|
(setq math-prime-test-cache-k 1
|
|
math-prime-test-cache-q
|
|
(math-div2 n)
|
|
math-prime-test-cache-nm1
|
|
(math-add n -1))
|
|
(while (math-evenp
|
|
math-prime-test-cache-q)
|
|
(setq math-prime-test-cache-k
|
|
(1+ math-prime-test-cache-k)
|
|
math-prime-test-cache-q
|
|
(math-div2
|
|
math-prime-test-cache-q)))
|
|
(setq iters (1+ iters))
|
|
(list 'maybe
|
|
0
|
|
(math-sub
|
|
100
|
|
(math-div
|
|
'(float 232 0)
|
|
(math-numdigs n))))))))))
|
|
((not (eq (car (nth 1 math-prime-test-cache)) 'maybe))
|
|
(nth 1 math-prime-test-cache))
|
|
(t ; Fermat step
|
|
(let* ((x (math-add (calcFunc-random (math-add n -2)) 2))
|
|
(y (math-pow-mod x math-prime-test-cache-q n))
|
|
(j 0))
|
|
(while (and (not (eq y 1))
|
|
(not (equal y math-prime-test-cache-nm1))
|
|
(< (setq j (1+ j)) math-prime-test-cache-k))
|
|
(setq y (math-mod (math-mul y y) n)))
|
|
(if (or (equal y math-prime-test-cache-nm1)
|
|
(and (eq y 1) (eq j 0)))
|
|
(list 'maybe
|
|
(1+ (nth 1 (nth 1 math-prime-test-cache)))
|
|
(math-mul (nth 2 (nth 1 math-prime-test-cache))
|
|
'(float 25 -2)))
|
|
'(nil unknown))))))
|
|
(setq math-prime-test-cache (list n res)
|
|
iters (if (eq (car res) 'maybe)
|
|
(1- iters)
|
|
0)))
|
|
res))
|
|
|
|
(defun calcFunc-prime (n &optional iters)
|
|
(or (math-num-integerp n) (math-reject-arg n 'integerp))
|
|
(or (not iters) (math-num-integerp iters) (math-reject-arg iters 'integerp))
|
|
(if (car (math-prime-test (math-trunc n) (math-trunc (or iters 1))))
|
|
1
|
|
0))
|
|
|
|
;;; Theory: summing base-10^6 digits modulo 111111 is "casting out 999999s".
|
|
;;; Initial probability that N is prime is 1/ln(N) = log10(e)/log10(N).
|
|
;;; After culling [2,3,5,7,11,13,37], probability of primality is 5.36 x more.
|
|
;;; Initial reported probability of non-primality is thus 100% - this.
|
|
;;; Each Fermat step multiplies this probability by 25%.
|
|
;;; The Fermat step is algorithm P from Knuth section 4.5.4.
|
|
|
|
|
|
(defun calcFunc-prfac (n)
|
|
(setq math-prime-factors-finished t)
|
|
(if (Math-messy-integerp n)
|
|
(setq n (math-trunc n)))
|
|
(if (Math-natnump n)
|
|
(if (Math-natnum-lessp 2 n)
|
|
(let (factors res p (i 0))
|
|
(while (and (not (eq n 1))
|
|
(< i (length math-primes-table)))
|
|
(setq p (aref math-primes-table i))
|
|
(while (eq (cdr (setq res (cond ((eq n p) (cons 1 0))
|
|
((eq n 1) (cons 0 1))
|
|
((consp n) (math-idivmod n p))
|
|
(t (cons (/ n p) (% n p))))))
|
|
0)
|
|
(math-working "factor" p)
|
|
(setq factors (nconc factors (list p))
|
|
n (car res)))
|
|
(or (eq n 1)
|
|
(Math-natnum-lessp p (car res))
|
|
(setq factors (nconc factors (list n))
|
|
n 1))
|
|
(setq i (1+ i)))
|
|
(or (setq math-prime-factors-finished (eq n 1))
|
|
(setq factors (nconc factors (list n))))
|
|
(cons 'vec factors))
|
|
(list 'vec n))
|
|
(if (Math-integerp n)
|
|
(if (eq n -1)
|
|
(list 'vec n)
|
|
(cons 'vec (cons -1 (cdr (calcFunc-prfac (math-neg n))))))
|
|
(calc-record-why 'integerp n)
|
|
(list 'calcFunc-prfac n))))
|
|
|
|
(defun calcFunc-totient (n)
|
|
(if (Math-messy-integerp n)
|
|
(setq n (math-trunc n)))
|
|
(if (Math-natnump n)
|
|
(if (Math-natnum-lessp n 2)
|
|
(if (Math-negp n)
|
|
(calcFunc-totient (math-abs n))
|
|
n)
|
|
(let ((factors (cdr (calcFunc-prfac n)))
|
|
p)
|
|
(if math-prime-factors-finished
|
|
(progn
|
|
(while factors
|
|
(setq p (car factors)
|
|
n (math-mul (math-div n p) (math-add p -1)))
|
|
(while (equal p (car factors))
|
|
(setq factors (cdr factors))))
|
|
n)
|
|
(calc-record-why "*Number too big to factor" n)
|
|
(list 'calcFunc-totient n))))
|
|
(calc-record-why 'natnump n)
|
|
(list 'calcFunc-totient n)))
|
|
|
|
(defun calcFunc-moebius (n)
|
|
(if (Math-messy-integerp n)
|
|
(setq n (math-trunc n)))
|
|
(if (and (Math-natnump n) (not (eq n 0)))
|
|
(if (Math-natnum-lessp n 2)
|
|
(if (Math-negp n)
|
|
(calcFunc-moebius (math-abs n))
|
|
1)
|
|
(let ((factors (cdr (calcFunc-prfac n)))
|
|
(mu 1))
|
|
(if math-prime-factors-finished
|
|
(progn
|
|
(while factors
|
|
(setq mu (if (equal (car factors) (nth 1 factors))
|
|
0 (math-neg mu))
|
|
factors (cdr factors)))
|
|
mu)
|
|
(calc-record-why "Number too big to factor" n)
|
|
(list 'calcFunc-moebius n))))
|
|
(calc-record-why 'posintp n)
|
|
(list 'calcFunc-moebius n)))
|
|
|
|
|
|
(defun calcFunc-nextprime (n &optional iters)
|
|
(if (Math-integerp n)
|
|
(if (Math-integer-negp n)
|
|
2
|
|
(if (and (integerp n) (< n 5003))
|
|
(math-next-small-prime (1+ n))
|
|
(if (math-evenp n)
|
|
(setq n (math-add n -1)))
|
|
(let (res)
|
|
(while (not (car (setq res (math-prime-test
|
|
(setq n (math-add n 2))
|
|
(or iters 1))))))
|
|
(if (and calc-verbose-nextprime
|
|
(eq (car res) 'maybe))
|
|
(calc-report-prime-test res)))
|
|
n))
|
|
(if (Math-realp n)
|
|
(calcFunc-nextprime (math-trunc n) iters)
|
|
(math-reject-arg n 'integerp))))
|
|
|
|
(defun calcFunc-prevprime (n &optional iters)
|
|
(if (Math-integerp n)
|
|
(if (Math-lessp n 4)
|
|
2
|
|
(if (math-evenp n)
|
|
(setq n (math-add n 1)))
|
|
(let (res)
|
|
(while (not (car (setq res (math-prime-test
|
|
(setq n (math-add n -2))
|
|
(or iters 1))))))
|
|
(if (and calc-verbose-nextprime
|
|
(eq (car res) 'maybe))
|
|
(calc-report-prime-test res)))
|
|
n)
|
|
(if (Math-realp n)
|
|
(calcFunc-prevprime (math-ceiling n) iters)
|
|
(math-reject-arg n 'integerp))))
|
|
|
|
(defun math-next-small-prime (n)
|
|
(if (and (integerp n) (> n 2))
|
|
(let ((lo -1)
|
|
(hi (length math-primes-table))
|
|
mid)
|
|
(while (> (- hi lo) 1)
|
|
(if (> n (aref math-primes-table
|
|
(setq mid (ash (+ lo hi) -1))))
|
|
(setq lo mid)
|
|
(setq hi mid)))
|
|
(aref math-primes-table hi))
|
|
2))
|
|
|
|
(provide 'calc-comb)
|
|
|
|
;;; arch-tag: 1d75ee9b-0815-42bd-a321-bb3dc001cc02
|
|
;;; calc-comb.el ends here
|