(math-approx-pi,math-approx-sqrt-e,math-approx-gamma-const):
[bpt/emacs.git] / lisp / calc / calc-funcs.el
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1;;; calc-funcs.el --- well-known functions for Calc
2
58ba2f8f 3;; Copyright (C) 1990, 1991, 1992, 1993, 2001, 2002, 2003, 2004,
f0fa15c5 4;; 2005, 2006, 2007 Free Software Foundation, Inc.
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5
6;; Author: David Gillespie <daveg@synaptics.com>
e8fff8ed 7;; Maintainer: Jay Belanger <jay.p.belanger@gmail.com>
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8
9;; This file is part of GNU Emacs.
10
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11;; GNU Emacs is free software; you can redistribute it and/or modify
12;; it under the terms of the GNU General Public License as published by
075969b4 13;; the Free Software Foundation; either version 3, or (at your option)
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14;; any later version.
15
136211a9 16;; GNU Emacs is distributed in the hope that it will be useful,
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17;; but WITHOUT ANY WARRANTY; without even the implied warranty of
18;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19;; GNU General Public License for more details.
20
21;; You should have received a copy of the GNU General Public License
22;; along with GNU Emacs; see the file COPYING. If not, write to the
23;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
24;; Boston, MA 02110-1301, USA.
136211a9 25
12f1951a 26;;; Commentary:
136211a9 27
12f1951a 28;;; Code:
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29
30;; This file is autoloaded from calc-ext.el.
136211a9 31
300f28d3 32(require 'calc-ext)
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33(require 'calc-macs)
34
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35(defun calc-inc-gamma (arg)
36 (interactive "P")
37 (calc-slow-wrapper
38 (if (calc-is-inverse)
39 (if (calc-is-hyperbolic)
40 (calc-binary-op "gamG" 'calcFunc-gammaG arg)
41 (calc-binary-op "gamQ" 'calcFunc-gammaQ arg))
42 (if (calc-is-hyperbolic)
43 (calc-binary-op "gamg" 'calcFunc-gammag arg)
bf77c646 44 (calc-binary-op "gamP" 'calcFunc-gammaP arg)))))
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45
46(defun calc-erf (arg)
47 (interactive "P")
48 (calc-slow-wrapper
49 (if (calc-is-inverse)
50 (calc-unary-op "erfc" 'calcFunc-erfc arg)
bf77c646 51 (calc-unary-op "erf" 'calcFunc-erf arg))))
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52
53(defun calc-erfc (arg)
54 (interactive "P")
55 (calc-invert-func)
bf77c646 56 (calc-erf arg))
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57
58(defun calc-beta (arg)
59 (interactive "P")
60 (calc-slow-wrapper
bf77c646 61 (calc-binary-op "beta" 'calcFunc-beta arg)))
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62
63(defun calc-inc-beta ()
64 (interactive)
65 (calc-slow-wrapper
66 (if (calc-is-hyperbolic)
67 (calc-enter-result 3 "betB" (cons 'calcFunc-betaB (calc-top-list-n 3)))
bf77c646 68 (calc-enter-result 3 "betI" (cons 'calcFunc-betaI (calc-top-list-n 3))))))
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69
70(defun calc-bessel-J (arg)
71 (interactive "P")
72 (calc-slow-wrapper
bf77c646 73 (calc-binary-op "besJ" 'calcFunc-besJ arg)))
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74
75(defun calc-bessel-Y (arg)
76 (interactive "P")
77 (calc-slow-wrapper
bf77c646 78 (calc-binary-op "besY" 'calcFunc-besY arg)))
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79
80(defun calc-bernoulli-number (arg)
81 (interactive "P")
82 (calc-slow-wrapper
83 (if (calc-is-hyperbolic)
84 (calc-binary-op "bern" 'calcFunc-bern arg)
bf77c646 85 (calc-unary-op "bern" 'calcFunc-bern arg))))
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86
87(defun calc-euler-number (arg)
88 (interactive "P")
89 (calc-slow-wrapper
90 (if (calc-is-hyperbolic)
91 (calc-binary-op "eulr" 'calcFunc-euler arg)
bf77c646 92 (calc-unary-op "eulr" 'calcFunc-euler arg))))
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93
94(defun calc-stirling-number (arg)
95 (interactive "P")
96 (calc-slow-wrapper
97 (if (calc-is-hyperbolic)
98 (calc-binary-op "str2" 'calcFunc-stir2 arg)
bf77c646 99 (calc-binary-op "str1" 'calcFunc-stir1 arg))))
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100
101(defun calc-utpb ()
102 (interactive)
bf77c646 103 (calc-prob-dist "b" 3))
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104
105(defun calc-utpc ()
106 (interactive)
bf77c646 107 (calc-prob-dist "c" 2))
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108
109(defun calc-utpf ()
110 (interactive)
bf77c646 111 (calc-prob-dist "f" 3))
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112
113(defun calc-utpn ()
114 (interactive)
bf77c646 115 (calc-prob-dist "n" 3))
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116
117(defun calc-utpp ()
118 (interactive)
bf77c646 119 (calc-prob-dist "p" 2))
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120
121(defun calc-utpt ()
122 (interactive)
bf77c646 123 (calc-prob-dist "t" 2))
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124
125(defun calc-prob-dist (letter nargs)
126 (calc-slow-wrapper
127 (if (calc-is-inverse)
128 (calc-enter-result nargs (concat "ltp" letter)
129 (append (list (intern (concat "calcFunc-ltp" letter))
130 (calc-top-n 1))
131 (calc-top-list-n (1- nargs) 2)))
132 (calc-enter-result nargs (concat "utp" letter)
133 (append (list (intern (concat "calcFunc-utp" letter))
134 (calc-top-n 1))
bf77c646 135 (calc-top-list-n (1- nargs) 2))))))
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136
137
138
139
140;;; Sources: Numerical Recipes, Press et al;
141;;; Handbook of Mathematical Functions, Abramowitz & Stegun.
142
143
144;;; Gamma function.
145
146(defun calcFunc-gamma (x)
147 (or (math-numberp x) (math-reject-arg x 'numberp))
bf77c646 148 (calcFunc-fact (math-add x -1)))
136211a9 149
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150(defun math-gammap1-raw (x &optional fprec nfprec)
151 "Compute gamma(1+X) to the appropriate precision."
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152 (or fprec
153 (setq fprec (math-float calc-internal-prec)
154 nfprec (math-float (- calc-internal-prec))))
155 (cond ((math-lessp-float (calcFunc-re x) fprec)
156 (if (math-lessp-float (calcFunc-re x) nfprec)
157 (math-neg (math-div
158 (math-pi)
159 (math-mul (math-gammap1-raw
160 (math-add (math-neg x)
161 '(float -1 0))
162 fprec nfprec)
163 (math-sin-raw
164 (math-mul (math-pi) x)))))
165 (let ((xplus1 (math-add x '(float 1 0))))
166 (math-div (math-gammap1-raw xplus1 fprec nfprec) xplus1))))
167 ((and (math-realp x)
168 (math-lessp-float '(float 736276 0) x))
169 (math-overflow))
170 (t ; re(x) now >= 10.0
171 (let ((xinv (math-div 1 x))
172 (lnx (math-ln-raw x)))
173 (math-mul (math-sqrt-two-pi)
174 (math-exp-raw
175 (math-gamma-series
176 (math-sub (math-mul (math-add x '(float 5 -1))
177 lnx)
178 x)
179 xinv
180 (math-sqr xinv)
181 '(float 0 0)
bf77c646 182 2)))))))
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183
184(defun math-gamma-series (sum x xinvsqr oterm n)
185 (math-working "gamma" sum)
186 (let* ((bn (math-bernoulli-number n))
187 (term (math-mul (math-div-float (math-float (nth 1 bn))
188 (math-float (* (nth 2 bn)
189 (* n (1- n)))))
190 x))
191 (next (math-add sum term)))
192 (if (math-nearly-equal sum next)
193 next
194 (if (> n (* 2 calc-internal-prec))
195 (progn
196 ;; Need this because series eventually diverges for large enough n.
197 (calc-record-why
198 "*Gamma computation stopped early, not all digits may be valid")
199 next)
bf77c646 200 (math-gamma-series next (math-mul x xinvsqr) xinvsqr term (+ n 2))))))
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201
202
203;;; Incomplete gamma function.
204
12f1951a 205(defvar math-current-gamma-value nil)
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206(defun calcFunc-gammaP (a x)
207 (if (equal x '(var inf var-inf))
208 '(float 1 0)
209 (math-inexact-result)
210 (or (Math-numberp a) (math-reject-arg a 'numberp))
211 (or (math-numberp x) (math-reject-arg x 'numberp))
212 (if (and (math-num-integerp a)
213 (integerp (setq a (math-trunc a)))
214 (> a 0) (< a 20))
215 (math-sub 1 (calcFunc-gammaQ a x))
216 (let ((math-current-gamma-value (calcFunc-gamma a)))
bf77c646 217 (math-div (calcFunc-gammag a x) math-current-gamma-value)))))
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218
219(defun calcFunc-gammaQ (a x)
220 (if (equal x '(var inf var-inf))
221 '(float 0 0)
222 (math-inexact-result)
223 (or (Math-numberp a) (math-reject-arg a 'numberp))
224 (or (math-numberp x) (math-reject-arg x 'numberp))
225 (if (and (math-num-integerp a)
226 (integerp (setq a (math-trunc a)))
227 (> a 0) (< a 20))
228 (let ((n 0)
229 (sum '(float 1 0))
230 (term '(float 1 0)))
231 (math-with-extra-prec 1
232 (while (< (setq n (1+ n)) a)
233 (setq term (math-div (math-mul term x) n)
234 sum (math-add sum term))
235 (math-working "gamma" sum))
236 (math-mul sum (calcFunc-exp (math-neg x)))))
237 (let ((math-current-gamma-value (calcFunc-gamma a)))
bf77c646 238 (math-div (calcFunc-gammaG a x) math-current-gamma-value)))))
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239
240(defun calcFunc-gammag (a x)
241 (if (equal x '(var inf var-inf))
242 (calcFunc-gamma a)
243 (math-inexact-result)
244 (or (Math-numberp a) (math-reject-arg a 'numberp))
245 (or (Math-numberp x) (math-reject-arg x 'numberp))
246 (math-with-extra-prec 2
247 (setq a (math-float a))
248 (setq x (math-float x))
249 (if (or (math-negp (calcFunc-re a))
250 (math-lessp-float (calcFunc-re x)
251 (math-add-float (calcFunc-re a)
252 '(float 1 0))))
253 (math-inc-gamma-series a x)
254 (math-sub (or math-current-gamma-value (calcFunc-gamma a))
bf77c646 255 (math-inc-gamma-cfrac a x))))))
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256
257(defun calcFunc-gammaG (a x)
258 (if (equal x '(var inf var-inf))
259 '(float 0 0)
260 (math-inexact-result)
261 (or (Math-numberp a) (math-reject-arg a 'numberp))
262 (or (Math-numberp x) (math-reject-arg x 'numberp))
263 (math-with-extra-prec 2
264 (setq a (math-float a))
265 (setq x (math-float x))
266 (if (or (math-negp (calcFunc-re a))
267 (math-lessp-float (calcFunc-re x)
268 (math-add-float (math-abs-approx a)
269 '(float 1 0))))
270 (math-sub (or math-current-gamma-value (calcFunc-gamma a))
271 (math-inc-gamma-series a x))
bf77c646 272 (math-inc-gamma-cfrac a x)))))
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273
274(defun math-inc-gamma-series (a x)
275 (if (Math-zerop x)
276 '(float 0 0)
277 (math-mul (math-exp-raw (math-sub (math-mul a (math-ln-raw x)) x))
278 (math-with-extra-prec 2
279 (let ((start (math-div '(float 1 0) a)))
bf77c646 280 (math-inc-gamma-series-step start start a x))))))
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281
282(defun math-inc-gamma-series-step (sum term a x)
283 (math-working "gamma" sum)
284 (setq a (math-add a '(float 1 0))
285 term (math-div (math-mul term x) a))
286 (let ((next (math-add sum term)))
287 (if (math-nearly-equal sum next)
288 next
bf77c646 289 (math-inc-gamma-series-step next term a x))))
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290
291(defun math-inc-gamma-cfrac (a x)
292 (if (Math-zerop x)
293 (or math-current-gamma-value (calcFunc-gamma a))
294 (math-mul (math-exp-raw (math-sub (math-mul a (math-ln-raw x)) x))
295 (math-inc-gamma-cfrac-step '(float 1 0) x
296 '(float 0 0) '(float 1 0)
297 '(float 1 0) '(float 1 0) '(float 0 0)
bf77c646 298 a x))))
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299
300(defun math-inc-gamma-cfrac-step (a0 a1 b0 b1 n fac g a x)
301 (let ((ana (math-sub n a))
302 (anf (math-mul n fac)))
303 (setq n (math-add n '(float 1 0))
304 a0 (math-mul (math-add a1 (math-mul a0 ana)) fac)
305 b0 (math-mul (math-add b1 (math-mul b0 ana)) fac)
306 a1 (math-add (math-mul x a0) (math-mul anf a1))
307 b1 (math-add (math-mul x b0) (math-mul anf b1)))
308 (if (math-zerop a1)
309 (math-inc-gamma-cfrac-step a0 a1 b0 b1 n fac g a x)
310 (setq fac (math-div '(float 1 0) a1))
311 (let ((next (math-mul b1 fac)))
312 (math-working "gamma" next)
313 (if (math-nearly-equal next g)
314 next
bf77c646 315 (math-inc-gamma-cfrac-step a0 a1 b0 b1 n fac next a x))))))
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316
317
318;;; Error function.
319
320(defun calcFunc-erf (x)
321 (if (equal x '(var inf var-inf))
322 '(float 1 0)
323 (if (equal x '(neg (var inf var-inf)))
324 '(float -1 0)
325 (if (Math-zerop x)
326 x
327 (let ((math-current-gamma-value (math-sqrt-pi)))
328 (math-to-same-complex-quad
329 (math-div (calcFunc-gammag '(float 5 -1)
330 (math-sqr (math-to-complex-quad-one x)))
331 math-current-gamma-value)
bf77c646 332 x))))))
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333
334(defun calcFunc-erfc (x)
335 (if (equal x '(var inf var-inf))
336 '(float 0 0)
337 (if (math-posp x)
338 (let ((math-current-gamma-value (math-sqrt-pi)))
339 (math-div (calcFunc-gammaG '(float 5 -1) (math-sqr x))
340 math-current-gamma-value))
bf77c646 341 (math-sub 1 (calcFunc-erf x)))))
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342
343(defun math-to-complex-quad-one (x)
344 (if (eq (car-safe x) 'polar) (setq x (math-complex x)))
345 (if (eq (car-safe x) 'cplx)
346 (list 'cplx (math-abs (nth 1 x)) (math-abs (nth 2 x)))
bf77c646 347 x))
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348
349(defun math-to-same-complex-quad (x y)
350 (if (eq (car-safe y) 'cplx)
351 (if (eq (car-safe x) 'cplx)
352 (list 'cplx
353 (if (math-negp (nth 1 y)) (math-neg (nth 1 x)) (nth 1 x))
354 (if (math-negp (nth 2 y)) (math-neg (nth 2 x)) (nth 2 x)))
355 (if (math-negp (nth 1 y)) (math-neg x) x))
356 (if (math-negp y)
357 (if (eq (car-safe x) 'cplx)
358 (list 'cplx (math-neg (nth 1 x)) (nth 2 x))
359 (math-neg x))
bf77c646 360 x)))
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361
362
363;;; Beta function.
364
365(defun calcFunc-beta (a b)
366 (if (math-num-integerp a)
367 (let ((am (math-add a -1)))
368 (or (math-numberp b) (math-reject-arg b 'numberp))
369 (math-div 1 (math-mul b (calcFunc-choose (math-add b am) am))))
370 (if (math-num-integerp b)
371 (calcFunc-beta b a)
372 (math-div (math-mul (calcFunc-gamma a) (calcFunc-gamma b))
bf77c646 373 (calcFunc-gamma (math-add a b))))))
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374
375
376;;; Incomplete beta function.
377
12f1951a 378(defvar math-current-beta-value nil)
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379(defun calcFunc-betaI (x a b)
380 (cond ((math-zerop x)
381 '(float 0 0))
382 ((math-equal-int x 1)
383 '(float 1 0))
384 ((or (math-zerop a)
385 (and (math-num-integerp a)
386 (math-negp a)))
387 (if (or (math-zerop b)
388 (and (math-num-integerp b)
389 (math-negp b)))
390 (math-reject-arg b 'range)
391 '(float 1 0)))
392 ((or (math-zerop b)
393 (and (math-num-integerp b)
394 (math-negp b)))
395 '(float 0 0))
396 ((not (math-numberp a)) (math-reject-arg a 'numberp))
397 ((not (math-numberp b)) (math-reject-arg b 'numberp))
398 ((math-inexact-result))
399 (t (let ((math-current-beta-value (calcFunc-beta a b)))
bf77c646 400 (math-div (calcFunc-betaB x a b) math-current-beta-value)))))
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401
402(defun calcFunc-betaB (x a b)
403 (cond
404 ((math-zerop x)
405 '(float 0 0))
406 ((math-equal-int x 1)
407 (calcFunc-beta a b))
408 ((not (math-numberp x)) (math-reject-arg x 'numberp))
409 ((not (math-numberp a)) (math-reject-arg a 'numberp))
410 ((not (math-numberp b)) (math-reject-arg b 'numberp))
411 ((math-zerop a) (math-reject-arg a 'nonzerop))
412 ((math-zerop b) (math-reject-arg b 'nonzerop))
413 ((and (math-num-integerp b)
414 (if (math-negp b)
415 (math-reject-arg b 'range)
416 (Math-natnum-lessp (setq b (math-trunc b)) 20)))
417 (and calc-symbolic-mode (or (math-floatp a) (math-floatp b))
418 (math-inexact-result))
419 (math-mul
420 (math-with-extra-prec 2
421 (let* ((i 0)
422 (term 1)
423 (sum (math-div term a)))
424 (while (< (setq i (1+ i)) b)
425 (setq term (math-mul (math-div (math-mul term (- i b)) i) x)
426 sum (math-add sum (math-div term (math-add a i))))
427 (math-working "beta" sum))
428 sum))
429 (math-pow x a)))
430 ((and (math-num-integerp a)
431 (if (math-negp a)
432 (math-reject-arg a 'range)
433 (Math-natnum-lessp (setq a (math-trunc a)) 20)))
434 (math-sub (or math-current-beta-value (calcFunc-beta a b))
435 (calcFunc-betaB (math-sub 1 x) b a)))
436 (t
437 (math-inexact-result)
438 (math-with-extra-prec 2
439 (setq x (math-float x))
440 (setq a (math-float a))
441 (setq b (math-float b))
442 (let ((bt (math-exp-raw (math-add (math-mul a (math-ln-raw x))
443 (math-mul b (math-ln-raw
444 (math-sub '(float 1 0)
445 x)))))))
446 (if (Math-lessp x (math-div (math-add a '(float 1 0))
447 (math-add (math-add a b) '(float 2 0))))
448 (math-div (math-mul bt (math-beta-cfrac a b x)) a)
449 (math-sub (or math-current-beta-value (calcFunc-beta a b))
450 (math-div (math-mul bt
451 (math-beta-cfrac b a (math-sub 1 x)))
bf77c646 452 b))))))))
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453
454(defun math-beta-cfrac (a b x)
455 (let ((qab (math-add a b))
456 (qap (math-add a '(float 1 0)))
457 (qam (math-add a '(float -1 0))))
458 (math-beta-cfrac-step '(float 1 0)
459 (math-sub '(float 1 0)
460 (math-div (math-mul qab x) qap))
461 '(float 1 0) '(float 1 0)
462 '(float 1 0)
bf77c646 463 qab qap qam a b x)))
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464
465(defun math-beta-cfrac-step (az bz am bm m qab qap qam a b x)
466 (let* ((two-m (math-mul m '(float 2 0)))
467 (d (math-div (math-mul (math-mul (math-sub b m) m) x)
468 (math-mul (math-add qam two-m) (math-add a two-m))))
469 (ap (math-add az (math-mul d am)))
470 (bp (math-add bz (math-mul d bm)))
471 (d2 (math-neg
472 (math-div (math-mul (math-mul (math-add a m) (math-add qab m)) x)
473 (math-mul (math-add qap two-m) (math-add a two-m)))))
474 (app (math-add ap (math-mul d2 az)))
475 (bpp (math-add bp (math-mul d2 bz)))
476 (next (math-div app bpp)))
477 (math-working "beta" next)
478 (if (math-nearly-equal next az)
479 next
480 (math-beta-cfrac-step next '(float 1 0)
481 (math-div ap bpp) (math-div bp bpp)
482 (math-add m '(float 1 0))
bf77c646 483 qab qap qam a b x))))
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484
485
486;;; Bessel functions.
487
488;;; Should generalize this to handle arbitrary precision!
489
490(defun calcFunc-besJ (v x)
491 (or (math-numberp v) (math-reject-arg v 'numberp))
492 (or (math-numberp x) (math-reject-arg x 'numberp))
493 (let ((calc-internal-prec (min 8 calc-internal-prec)))
494 (math-with-extra-prec 3
495 (setq x (math-float (math-normalize x)))
496 (setq v (math-float (math-normalize v)))
497 (cond ((math-zerop x)
498 (if (math-zerop v)
499 '(float 1 0)
500 '(float 0 0)))
501 ((math-inexact-result))
502 ((not (math-num-integerp v))
503 (let ((start (math-div 1 (calcFunc-fact v))))
504 (math-mul (math-besJ-series start start
505 0
506 (math-mul '(float -25 -2)
507 (math-sqr x))
508 v)
509 (math-pow (math-div x 2) v))))
510 ((math-negp (setq v (math-trunc v)))
511 (if (math-oddp v)
512 (math-neg (calcFunc-besJ (math-neg v) x))
513 (calcFunc-besJ (math-neg v) x)))
514 ((eq v 0)
515 (math-besJ0 x))
516 ((eq v 1)
517 (math-besJ1 x))
518 ((Math-lessp v (math-abs-approx x))
519 (let ((j 0)
520 (bjm (math-besJ0 x))
521 (bj (math-besJ1 x))
522 (two-over-x (math-div 2 x))
523 bjp)
524 (while (< (setq j (1+ j)) v)
525 (setq bjp (math-sub (math-mul (math-mul j two-over-x) bj)
526 bjm)
527 bjm bj
528 bj bjp))
529 bj))
530 (t
531 (if (Math-lessp 100 v) (math-reject-arg v 'range))
532 (let* ((j (logior (+ v (math-isqrt-small (* 40 v))) 1))
533 (two-over-x (math-div 2 x))
534 (jsum nil)
535 (bjp '(float 0 0))
536 (sum '(float 0 0))
537 (bj '(float 1 0))
538 bjm ans)
539 (while (> (setq j (1- j)) 0)
540 (setq bjm (math-sub (math-mul (math-mul j two-over-x) bj)
541 bjp)
542 bjp bj
543 bj bjm)
544 (if (> (nth 2 (math-abs-approx bj)) 10)
545 (setq bj (math-mul bj '(float 1 -10))
546 bjp (math-mul bjp '(float 1 -10))
547 ans (and ans (math-mul ans '(float 1 -10)))
548 sum (math-mul sum '(float 1 -10))))
549 (or (setq jsum (not jsum))
550 (setq sum (math-add sum bj)))
551 (if (= j v)
552 (setq ans bjp)))
bf77c646 553 (math-div ans (math-sub (math-mul 2 sum) bj))))))))
136211a9
EZ
554
555(defun math-besJ-series (sum term k zz vk)
556 (math-working "besJ" sum)
557 (setq k (1+ k)
558 vk (math-add 1 vk)
559 term (math-div (math-mul term zz) (math-mul k vk)))
560 (let ((next (math-add sum term)))
561 (if (math-nearly-equal next sum)
562 next
bf77c646 563 (math-besJ-series next term k zz vk))))
136211a9
EZ
564
565(defun math-besJ0 (x &optional yflag)
566 (cond ((and (not yflag) (math-negp (calcFunc-re x)))
567 (math-besJ0 (math-neg x)))
568 ((Math-lessp '(float 8 0) (math-abs-approx x))
569 (let* ((z (math-div '(float 8 0) x))
570 (y (math-sqr z))
a8775b6d
JB
571 (xx (math-add x
572 (eval-when-compile
f83b9601 573 (math-read-number-simple "-0.785398164"))))
136211a9 574 (a1 (math-poly-eval y
a8775b6d
JB
575 (eval-when-compile
576 (list
f83b9601
JB
577 (math-read-number-simple "0.0000002093887211")
578 (math-read-number-simple "-0.000002073370639")
579 (math-read-number-simple "0.00002734510407")
580 (math-read-number-simple "-0.001098628627")
a8775b6d 581 '(float 1 0)))))
136211a9 582 (a2 (math-poly-eval y
a8775b6d
JB
583 (eval-when-compile
584 (list
f83b9601
JB
585 (math-read-number-simple "-0.0000000934935152")
586 (math-read-number-simple "0.0000007621095161")
587 (math-read-number-simple "-0.000006911147651")
588 (math-read-number-simple "0.0001430488765")
589 (math-read-number-simple "-0.01562499995")))))
136211a9
EZ
590 (sc (math-sin-cos-raw xx)))
591 (if yflag
592 (setq sc (cons (math-neg (cdr sc)) (car sc))))
593 (math-mul (math-sqrt
a8775b6d 594 (math-div (eval-when-compile
f83b9601 595 (math-read-number-simple "0.636619722"))
a8775b6d 596 x))
136211a9
EZ
597 (math-sub (math-mul (cdr sc) a1)
598 (math-mul (car sc) (math-mul z a2))))))
599 (t
600 (let ((y (math-sqr x)))
601 (math-div (math-poly-eval y
a8775b6d
JB
602 (eval-when-compile
603 (list
f83b9601
JB
604 (math-read-number-simple "-184.9052456")
605 (math-read-number-simple "77392.33017")
606 (math-read-number-simple "-11214424.18")
607 (math-read-number-simple "651619640.7")
608 (math-read-number-simple "-13362590354.0")
609 (math-read-number-simple "57568490574.0"))))
136211a9 610 (math-poly-eval y
a8775b6d
JB
611 (eval-when-compile
612 (list
613 '(float 1 0)
f83b9601
JB
614 (math-read-number-simple "267.8532712")
615 (math-read-number-simple "59272.64853")
616 (math-read-number-simple "9494680.718")
617 (math-read-number-simple "1029532985.0")
618 (math-read-number-simple "57568490411.0")))))))))
136211a9
EZ
619
620(defun math-besJ1 (x &optional yflag)
621 (cond ((and (math-negp (calcFunc-re x)) (not yflag))
622 (math-neg (math-besJ1 (math-neg x))))
623 ((Math-lessp '(float 8 0) (math-abs-approx x))
624 (let* ((z (math-div '(float 8 0) x))
625 (y (math-sqr z))
a8775b6d 626 (xx (math-add x (eval-when-compile
f83b9601 627 (math-read-number-simple "-2.356194491"))))
136211a9 628 (a1 (math-poly-eval y
a8775b6d
JB
629 (eval-when-compile
630 (list
f83b9601
JB
631 (math-read-number-simple "-0.000000240337019")
632 (math-read-number-simple "0.000002457520174")
633 (math-read-number-simple "-0.00003516396496")
a8775b6d
JB
634 '(float 183105 -8)
635 '(float 1 0)))))
136211a9 636 (a2 (math-poly-eval y
a8775b6d
JB
637 (eval-when-compile
638 (list
f83b9601
JB
639 (math-read-number-simple "0.000000105787412")
640 (math-read-number-simple "-0.00000088228987")
641 (math-read-number-simple "0.000008449199096")
642 (math-read-number-simple "-0.0002002690873")
643 (math-read-number-simple "0.04687499995")))))
136211a9
EZ
644 (sc (math-sin-cos-raw xx)))
645 (if yflag
646 (setq sc (cons (math-neg (cdr sc)) (car sc)))
647 (if (math-negp x)
648 (setq sc (cons (math-neg (car sc)) (math-neg (cdr sc))))))
a8775b6d
JB
649 (math-mul (math-sqrt (math-div
650 (eval-when-compile
f83b9601 651 (math-read-number-simple "0.636619722"))
a8775b6d 652 x))
136211a9
EZ
653 (math-sub (math-mul (cdr sc) a1)
654 (math-mul (car sc) (math-mul z a2))))))
655 (t
656 (let ((y (math-sqr x)))
657 (math-mul
658 x
659 (math-div (math-poly-eval y
a8775b6d
JB
660 (eval-when-compile
661 (list
f83b9601
JB
662 (math-read-number-simple "-30.16036606")
663 (math-read-number-simple "15704.4826")
664 (math-read-number-simple "-2972611.439")
665 (math-read-number-simple "242396853.1")
666 (math-read-number-simple "-7895059235.0")
667 (math-read-number-simple "72362614232.0"))))
136211a9 668 (math-poly-eval y
a8775b6d
JB
669 (eval-when-compile
670 (list
671 '(float 1 0)
f83b9601
JB
672 (math-read-number-simple "376.9991397")
673 (math-read-number-simple "99447.43394")
674 (math-read-number-simple "18583304.74")
675 (math-read-number-simple "2300535178.0")
676 (math-read-number-simple "144725228442.0"))))))))))
136211a9
EZ
677
678(defun calcFunc-besY (v x)
679 (math-inexact-result)
680 (or (math-numberp v) (math-reject-arg v 'numberp))
681 (or (math-numberp x) (math-reject-arg x 'numberp))
682 (let ((calc-internal-prec (min 8 calc-internal-prec)))
683 (math-with-extra-prec 3
684 (setq x (math-float (math-normalize x)))
685 (setq v (math-float (math-normalize v)))
686 (cond ((not (math-num-integerp v))
687 (let ((sc (math-sin-cos-raw (math-mul v (math-pi)))))
688 (math-div (math-sub (math-mul (calcFunc-besJ v x) (cdr sc))
689 (calcFunc-besJ (math-neg v) x))
690 (car sc))))
691 ((math-negp (setq v (math-trunc v)))
692 (if (math-oddp v)
693 (math-neg (calcFunc-besY (math-neg v) x))
694 (calcFunc-besY (math-neg v) x)))
695 ((eq v 0)
696 (math-besY0 x))
697 ((eq v 1)
698 (math-besY1 x))
699 (t
700 (let ((j 0)
701 (bym (math-besY0 x))
702 (by (math-besY1 x))
703 (two-over-x (math-div 2 x))
704 byp)
705 (while (< (setq j (1+ j)) v)
706 (setq byp (math-sub (math-mul (math-mul j two-over-x) by)
707 bym)
708 bym by
709 by byp))
bf77c646 710 by))))))
136211a9
EZ
711
712(defun math-besY0 (x)
713 (cond ((Math-lessp (math-abs-approx x) '(float 8 0))
714 (let ((y (math-sqr x)))
715 (math-add
716 (math-div (math-poly-eval y
a8775b6d
JB
717 (eval-when-compile
718 (list
f83b9601
JB
719 (math-read-number-simple "228.4622733")
720 (math-read-number-simple "-86327.92757")
721 (math-read-number-simple "10879881.29")
722 (math-read-number-simple "-512359803.6")
723 (math-read-number-simple "7062834065.0")
724 (math-read-number-simple "-2957821389.0"))))
136211a9 725 (math-poly-eval y
a8775b6d
JB
726 (eval-when-compile
727 (list
728 '(float 1 0)
f83b9601
JB
729 (math-read-number-simple "226.1030244")
730 (math-read-number-simple "47447.2647")
731 (math-read-number-simple "7189466.438")
732 (math-read-number-simple "745249964.8")
733 (math-read-number-simple "40076544269.0")))))
a8775b6d 734 (math-mul (eval-when-compile
f83b9601 735 (math-read-number-simple "0.636619772"))
136211a9
EZ
736 (math-mul (math-besJ0 x) (math-ln-raw x))))))
737 ((math-negp (calcFunc-re x))
738 (math-add (math-besJ0 (math-neg x) t)
739 (math-mul '(cplx 0 2)
740 (math-besJ0 (math-neg x)))))
741 (t
bf77c646 742 (math-besJ0 x t))))
136211a9
EZ
743
744(defun math-besY1 (x)
745 (cond ((Math-lessp (math-abs-approx x) '(float 8 0))
746 (let ((y (math-sqr x)))
747 (math-add
748 (math-mul
749 x
750 (math-div (math-poly-eval y
a8775b6d
JB
751 (eval-when-compile
752 (list
f83b9601
JB
753 (math-read-number-simple "8511.937935")
754 (math-read-number-simple "-4237922.726")
755 (math-read-number-simple "734926455.1")
756 (math-read-number-simple "-51534381390.0")
757 (math-read-number-simple "1275274390000.0")
758 (math-read-number-simple "-4900604943000.0"))))
136211a9 759 (math-poly-eval y
a8775b6d
JB
760 (eval-when-compile
761 (list
762 '(float 1 0)
f83b9601
JB
763 (math-read-number-simple "354.9632885")
764 (math-read-number-simple "102042.605")
765 (math-read-number-simple "22459040.02")
766 (math-read-number-simple "3733650367.0")
767 (math-read-number-simple "424441966400.0")
768 (math-read-number-simple "24995805700000.0"))))))
769 (math-mul (eval-when-compile (math-read-number-simple "0.636619772"))
a8775b6d 770 (math-sub (math-mul (math-besJ1 x) (math-ln-raw x))
136211a9
EZ
771 (math-div 1 x))))))
772 ((math-negp (calcFunc-re x))
773 (math-neg
774 (math-add (math-besJ1 (math-neg x) t)
775 (math-mul '(cplx 0 2)
776 (math-besJ1 (math-neg x))))))
777 (t
bf77c646 778 (math-besJ1 x t))))
136211a9
EZ
779
780(defun math-poly-eval (x coefs)
781 (let ((accum (car coefs)))
782 (while (setq coefs (cdr coefs))
783 (setq accum (math-add (car coefs) (math-mul accum x))))
bf77c646 784 accum))
136211a9
EZ
785
786
787;;;; Bernoulli and Euler polynomials and numbers.
788
789(defun calcFunc-bern (n &optional x)
790 (if (and x (not (math-zerop x)))
791 (if (and calc-symbolic-mode (math-floatp x))
792 (math-inexact-result)
793 (math-build-polynomial-expr (math-bernoulli-coefs n) x))
794 (or (math-num-natnump n) (math-reject-arg n 'natnump))
795 (if (consp n)
796 (progn
797 (math-inexact-result)
798 (math-float (math-bernoulli-number (math-trunc n))))
bf77c646 799 (math-bernoulli-number n))))
136211a9
EZ
800
801(defun calcFunc-euler (n &optional x)
802 (or (math-num-natnump n) (math-reject-arg n 'natnump))
803 (if x
804 (let* ((n1 (math-add n 1))
805 (coefs (math-bernoulli-coefs n1))
806 (fac (math-div (math-pow 2 n1) n1))
807 (k -1)
808 (x1 (math-div (math-add x 1) 2))
809 (x2 (math-div x 2)))
810 (if (math-numberp x)
811 (if (and calc-symbolic-mode (math-floatp x))
812 (math-inexact-result)
813 (math-mul fac
814 (math-sub (math-build-polynomial-expr coefs x1)
815 (math-build-polynomial-expr coefs x2))))
816 (calcFunc-collect
817 (math-reduce-vec
818 'math-add
819 (cons 'vec
820 (mapcar (function
821 (lambda (c)
822 (setq k (1+ k))
823 (math-mul (math-mul fac c)
824 (math-sub (math-pow x1 k)
825 (math-pow x2 k)))))
826 coefs)))
827 x)))
828 (math-mul (math-pow 2 n)
829 (if (consp n)
830 (progn
831 (math-inexact-result)
832 (calcFunc-euler n '(float 5 -1)))
bf77c646 833 (calcFunc-euler n '(frac 1 2))))))
136211a9 834
a8775b6d
JB
835(defvar math-bernoulli-b-cache
836 (eval-when-compile
837 (list
838 (list 'frac
839 -174611
f83b9601 840 (math-read-number-simple "802857662698291200000"))
a8775b6d
JB
841 (list 'frac
842 43867
f83b9601 843 (math-read-number-simple "5109094217170944000"))
a8775b6d
JB
844 (list 'frac
845 -3617
f83b9601 846 (math-read-number-simple "10670622842880000"))
a8775b6d
JB
847 (list 'frac
848 1
f83b9601 849 (math-read-number-simple "74724249600"))
a8775b6d
JB
850 (list 'frac
851 -691
f83b9601 852 (math-read-number-simple "1307674368000"))
a8775b6d
JB
853 (list 'frac
854 1
f83b9601 855 (math-read-number-simple "47900160"))
a8775b6d
JB
856 (list 'frac
857 -1
f83b9601 858 (math-read-number-simple "1209600"))
a8775b6d
JB
859 (list 'frac
860 1
861 30240)
862 (list 'frac
863 -1
864 720)
865 (list 'frac
866 1
867 12)
868 1 )))
12f1951a
CW
869
870(defvar math-bernoulli-B-cache '((frac -174611 330) (frac 43867 798)
871 (frac -3617 510) (frac 7 6) (frac -691 2730)
872 (frac 5 66) (frac -1 30) (frac 1 42)
873 (frac -1 30) (frac 1 6) 1 ))
874
875(defvar math-bernoulli-cache-size 11)
136211a9
EZ
876(defun math-bernoulli-coefs (n)
877 (let* ((coefs (list (calcFunc-bern n)))
878 (nn (math-trunc n))
879 (k nn)
880 (term nn)
881 coef
882 (calc-prefer-frac (or (integerp n) calc-prefer-frac)))
883 (while (>= (setq k (1- k)) 0)
884 (setq term (math-div term (- nn k))
885 coef (math-mul term (math-bernoulli-number k))
886 coefs (cons (if (consp n) (math-float coef) coef) coefs)
887 term (math-mul term k)))
bf77c646 888 (nreverse coefs)))
136211a9
EZ
889
890(defun math-bernoulli-number (n)
891 (if (= (% n 2) 1)
892 (if (= n 1)
893 '(frac -1 2)
894 0)
895 (setq n (/ n 2))
896 (while (>= n math-bernoulli-cache-size)
897 (let* ((sum 0)
898 (nk 1) ; nk = n-k+1
899 (fact 1) ; fact = (n-k+1)!
900 ofact
901 (p math-bernoulli-b-cache)
902 (calc-prefer-frac t))
903 (math-working "bernoulli B" (* 2 math-bernoulli-cache-size))
904 (while p
905 (setq nk (+ nk 2)
906 ofact fact
907 fact (math-mul fact (* nk (1- nk)))
908 sum (math-add sum (math-div (car p) fact))
909 p (cdr p)))
910 (setq ofact (math-mul ofact (1- nk))
911 sum (math-sub (math-div '(frac 1 2) ofact) sum)
912 math-bernoulli-b-cache (cons sum math-bernoulli-b-cache)
913 math-bernoulli-B-cache (cons (math-mul sum ofact)
914 math-bernoulli-B-cache)
915 math-bernoulli-cache-size (1+ math-bernoulli-cache-size))))
bf77c646 916 (nth (- math-bernoulli-cache-size n 1) math-bernoulli-B-cache)))
136211a9
EZ
917
918;;; Bn = n! bn
919;;; bn = - sum_k=0^n-1 bk / (n-k+1)!
920
921;;; A faster method would be to use "tangent numbers", c.f., Concrete
922;;; Mathematics pg. 273.
923
136211a9
EZ
924
925;;; Probability distributions.
926
927;;; Binomial.
928(defun calcFunc-utpb (x n p)
929 (if math-expand-formulas
930 (math-normalize (list 'calcFunc-betaI p x (list '+ (list '- n x) 1)))
bf77c646 931 (calcFunc-betaI p x (math-add (math-sub n x) 1))))
136211a9
EZ
932(put 'calcFunc-utpb 'math-expandable t)
933
934(defun calcFunc-ltpb (x n p)
bf77c646 935 (math-sub 1 (calcFunc-utpb x n p)))
136211a9
EZ
936(put 'calcFunc-ltpb 'math-expandable t)
937
938;;; Chi-square.
939(defun calcFunc-utpc (chisq v)
940 (if math-expand-formulas
941 (math-normalize (list 'calcFunc-gammaQ (list '/ v 2) (list '/ chisq 2)))
bf77c646 942 (calcFunc-gammaQ (math-div v 2) (math-div chisq 2))))
136211a9
EZ
943(put 'calcFunc-utpc 'math-expandable t)
944
945(defun calcFunc-ltpc (chisq v)
946 (if math-expand-formulas
947 (math-normalize (list 'calcFunc-gammaP (list '/ v 2) (list '/ chisq 2)))
bf77c646 948 (calcFunc-gammaP (math-div v 2) (math-div chisq 2))))
136211a9
EZ
949(put 'calcFunc-ltpc 'math-expandable t)
950
951;;; F-distribution.
952(defun calcFunc-utpf (f v1 v2)
953 (if math-expand-formulas
954 (math-normalize (list 'calcFunc-betaI
955 (list '/ v2 (list '+ v2 (list '* v1 f)))
956 (list '/ v2 2)
957 (list '/ v1 2)))
958 (calcFunc-betaI (math-div v2 (math-add v2 (math-mul v1 f)))
959 (math-div v2 2)
bf77c646 960 (math-div v1 2))))
136211a9
EZ
961(put 'calcFunc-utpf 'math-expandable t)
962
963(defun calcFunc-ltpf (f v1 v2)
bf77c646 964 (math-sub 1 (calcFunc-utpf f v1 v2)))
136211a9
EZ
965(put 'calcFunc-ltpf 'math-expandable t)
966
967;;; Normal.
968(defun calcFunc-utpn (x mean sdev)
969 (if math-expand-formulas
970 (math-normalize
971 (list '/
972 (list '+ 1
973 (list 'calcFunc-erf
974 (list '/ (list '- mean x)
975 (list '* sdev (list 'calcFunc-sqrt 2)))))
976 2))
977 (math-mul (math-add '(float 1 0)
978 (calcFunc-erf
979 (math-div (math-sub mean x)
980 (math-mul sdev (math-sqrt-2)))))
bf77c646 981 '(float 5 -1))))
136211a9
EZ
982(put 'calcFunc-utpn 'math-expandable t)
983
984(defun calcFunc-ltpn (x mean sdev)
985 (if math-expand-formulas
986 (math-normalize
987 (list '/
988 (list '+ 1
989 (list 'calcFunc-erf
990 (list '/ (list '- x mean)
991 (list '* sdev (list 'calcFunc-sqrt 2)))))
992 2))
993 (math-mul (math-add '(float 1 0)
994 (calcFunc-erf
995 (math-div (math-sub x mean)
996 (math-mul sdev (math-sqrt-2)))))
bf77c646 997 '(float 5 -1))))
136211a9
EZ
998(put 'calcFunc-ltpn 'math-expandable t)
999
1000;;; Poisson.
1001(defun calcFunc-utpp (n x)
1002 (if math-expand-formulas
1003 (math-normalize (list 'calcFunc-gammaP x n))
bf77c646 1004 (calcFunc-gammaP x n)))
136211a9
EZ
1005(put 'calcFunc-utpp 'math-expandable t)
1006
1007(defun calcFunc-ltpp (n x)
1008 (if math-expand-formulas
1009 (math-normalize (list 'calcFunc-gammaQ x n))
bf77c646 1010 (calcFunc-gammaQ x n)))
136211a9
EZ
1011(put 'calcFunc-ltpp 'math-expandable t)
1012
1013;;; Student's t. (As defined in Abramowitz & Stegun and Numerical Recipes.)
1014(defun calcFunc-utpt (tt v)
1015 (if math-expand-formulas
1016 (math-normalize (list 'calcFunc-betaI
1017 (list '/ v (list '+ v (list '^ tt 2)))
1018 (list '/ v 2)
1019 '(float 5 -1)))
1020 (calcFunc-betaI (math-div v (math-add v (math-sqr tt)))
1021 (math-div v 2)
bf77c646 1022 '(float 5 -1))))
136211a9
EZ
1023(put 'calcFunc-utpt 'math-expandable t)
1024
1025(defun calcFunc-ltpt (tt v)
bf77c646 1026 (math-sub 1 (calcFunc-utpt tt v)))
136211a9
EZ
1027(put 'calcFunc-ltpt 'math-expandable t)
1028
300f28d3 1029(provide 'calc-funcs)
136211a9 1030
ab5796a9 1031;;; arch-tag: 421ddb7a-550f-4dda-a31c-06638ebfc43a
bf77c646 1032;;; calc-funcs.el ends here