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3132f345 CW |
1 | ;;; calc-poly.el --- polynomial functions for Calc |
2 | ||
bf77c646 | 3 | ;; Copyright (C) 1990, 1991, 1992, 1993, 2001 Free Software Foundation, Inc. |
3132f345 CW |
4 | |
5 | ;; Author: David Gillespie <daveg@synaptics.com> | |
e1030072 | 6 | ;; Maintainer: Jay Belanger <belanger@truman.edu> |
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7 | |
8 | ;; This file is part of GNU Emacs. | |
9 | ||
10 | ;; GNU Emacs is distributed in the hope that it will be useful, | |
11 | ;; but WITHOUT ANY WARRANTY. No author or distributor | |
12 | ;; accepts responsibility to anyone for the consequences of using it | |
13 | ;; or for whether it serves any particular purpose or works at all, | |
14 | ;; unless he says so in writing. Refer to the GNU Emacs General Public | |
15 | ;; License for full details. | |
16 | ||
17 | ;; Everyone is granted permission to copy, modify and redistribute | |
18 | ;; GNU Emacs, but only under the conditions described in the | |
19 | ;; GNU Emacs General Public License. A copy of this license is | |
20 | ;; supposed to have been given to you along with GNU Emacs so you | |
21 | ;; can know your rights and responsibilities. It should be in a | |
22 | ;; file named COPYING. Among other things, the copyright notice | |
23 | ;; and this notice must be preserved on all copies. | |
24 | ||
3132f345 | 25 | ;;; Commentary: |
136211a9 | 26 | |
3132f345 | 27 | ;;; Code: |
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28 | |
29 | ;; This file is autoloaded from calc-ext.el. | |
30 | (require 'calc-ext) | |
31 | ||
32 | (require 'calc-macs) | |
33 | ||
34 | (defun calc-Need-calc-poly () nil) | |
35 | ||
36 | ||
37 | (defun calcFunc-pcont (expr &optional var) | |
38 | (cond ((Math-primp expr) | |
39 | (cond ((Math-zerop expr) 1) | |
40 | ((Math-messy-integerp expr) (math-trunc expr)) | |
41 | ((Math-objectp expr) expr) | |
42 | ((or (equal expr var) (not var)) 1) | |
43 | (t expr))) | |
44 | ((eq (car expr) '*) | |
45 | (math-mul (calcFunc-pcont (nth 1 expr) var) | |
46 | (calcFunc-pcont (nth 2 expr) var))) | |
47 | ((eq (car expr) '/) | |
48 | (math-div (calcFunc-pcont (nth 1 expr) var) | |
49 | (calcFunc-pcont (nth 2 expr) var))) | |
50 | ((and (eq (car expr) '^) (Math-natnump (nth 2 expr))) | |
51 | (math-pow (calcFunc-pcont (nth 1 expr) var) (nth 2 expr))) | |
52 | ((memq (car expr) '(neg polar)) | |
53 | (calcFunc-pcont (nth 1 expr) var)) | |
54 | ((consp var) | |
55 | (let ((p (math-is-polynomial expr var))) | |
56 | (if p | |
57 | (let ((lead (nth (1- (length p)) p)) | |
58 | (cont (math-poly-gcd-list p))) | |
59 | (if (math-guess-if-neg lead) | |
60 | (math-neg cont) | |
61 | cont)) | |
62 | 1))) | |
63 | ((memq (car expr) '(+ - cplx sdev)) | |
64 | (let ((cont (calcFunc-pcont (nth 1 expr) var))) | |
65 | (if (eq cont 1) | |
66 | 1 | |
67 | (let ((c2 (calcFunc-pcont (nth 2 expr) var))) | |
68 | (if (and (math-negp cont) | |
69 | (if (eq (car expr) '-) (math-posp c2) (math-negp c2))) | |
70 | (math-neg (math-poly-gcd cont c2)) | |
71 | (math-poly-gcd cont c2)))))) | |
72 | (var expr) | |
bf77c646 | 73 | (t 1))) |
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74 | |
75 | (defun calcFunc-pprim (expr &optional var) | |
76 | (let ((cont (calcFunc-pcont expr var))) | |
77 | (if (math-equal-int cont 1) | |
78 | expr | |
bf77c646 | 79 | (math-poly-div-exact expr cont var)))) |
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80 | |
81 | (defun math-div-poly-const (expr c) | |
82 | (cond ((memq (car-safe expr) '(+ -)) | |
83 | (list (car expr) | |
84 | (math-div-poly-const (nth 1 expr) c) | |
85 | (math-div-poly-const (nth 2 expr) c))) | |
bf77c646 | 86 | (t (math-div expr c)))) |
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87 | |
88 | (defun calcFunc-pdeg (expr &optional var) | |
89 | (if (Math-zerop expr) | |
90 | '(neg (var inf var-inf)) | |
91 | (if var | |
92 | (or (math-polynomial-p expr var) | |
93 | (math-reject-arg expr "Expected a polynomial")) | |
bf77c646 | 94 | (math-poly-degree expr)))) |
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95 | |
96 | (defun math-poly-degree (expr) | |
97 | (cond ((Math-primp expr) | |
98 | (if (eq (car-safe expr) 'var) 1 0)) | |
99 | ((eq (car expr) 'neg) | |
100 | (math-poly-degree (nth 1 expr))) | |
101 | ((eq (car expr) '*) | |
102 | (+ (math-poly-degree (nth 1 expr)) | |
103 | (math-poly-degree (nth 2 expr)))) | |
104 | ((eq (car expr) '/) | |
105 | (- (math-poly-degree (nth 1 expr)) | |
106 | (math-poly-degree (nth 2 expr)))) | |
107 | ((and (eq (car expr) '^) (natnump (nth 2 expr))) | |
108 | (* (math-poly-degree (nth 1 expr)) (nth 2 expr))) | |
109 | ((memq (car expr) '(+ -)) | |
110 | (max (math-poly-degree (nth 1 expr)) | |
111 | (math-poly-degree (nth 2 expr)))) | |
bf77c646 | 112 | (t 1))) |
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113 | |
114 | (defun calcFunc-plead (expr var) | |
115 | (cond ((eq (car-safe expr) '*) | |
116 | (math-mul (calcFunc-plead (nth 1 expr) var) | |
117 | (calcFunc-plead (nth 2 expr) var))) | |
118 | ((eq (car-safe expr) '/) | |
119 | (math-div (calcFunc-plead (nth 1 expr) var) | |
120 | (calcFunc-plead (nth 2 expr) var))) | |
121 | ((and (eq (car-safe expr) '^) (math-natnump (nth 2 expr))) | |
122 | (math-pow (calcFunc-plead (nth 1 expr) var) (nth 2 expr))) | |
123 | ((Math-primp expr) | |
124 | (if (equal expr var) | |
125 | 1 | |
126 | expr)) | |
127 | (t | |
128 | (let ((p (math-is-polynomial expr var))) | |
129 | (if (cdr p) | |
130 | (nth (1- (length p)) p) | |
bf77c646 | 131 | 1))))) |
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132 | |
133 | ||
134 | ||
135 | ||
136 | ||
137 | ;;; Polynomial quotient, remainder, and GCD. | |
138 | ;;; Originally by Ove Ewerlid (ewerlid@mizar.DoCS.UU.SE). | |
139 | ;;; Modifications and simplifications by daveg. | |
140 | ||
3132f345 | 141 | (defvar math-poly-modulus 1) |
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142 | |
143 | ;;; Return gcd of two polynomials | |
144 | (defun calcFunc-pgcd (pn pd) | |
145 | (if (math-any-floats pn) | |
146 | (math-reject-arg pn "Coefficients must be rational")) | |
147 | (if (math-any-floats pd) | |
148 | (math-reject-arg pd "Coefficients must be rational")) | |
149 | (let ((calc-prefer-frac t) | |
150 | (math-poly-modulus (math-poly-modulus pn pd))) | |
bf77c646 | 151 | (math-poly-gcd pn pd))) |
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152 | |
153 | ;;; Return only quotient to top of stack (nil if zero) | |
e1030072 JB |
154 | |
155 | ;; calc-poly-div-remainder is a local variable for | |
156 | ;; calc-poly-div (in calc-alg.el), but is used by | |
157 | ;; calcFunc-pdiv, which is called by calc-poly-div. | |
158 | (defvar calc-poly-div-remainder) | |
159 | ||
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160 | (defun calcFunc-pdiv (pn pd &optional base) |
161 | (let* ((calc-prefer-frac t) | |
162 | (math-poly-modulus (math-poly-modulus pn pd)) | |
163 | (res (math-poly-div pn pd base))) | |
164 | (setq calc-poly-div-remainder (cdr res)) | |
bf77c646 | 165 | (car res))) |
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166 | |
167 | ;;; Return only remainder to top of stack | |
168 | (defun calcFunc-prem (pn pd &optional base) | |
169 | (let ((calc-prefer-frac t) | |
170 | (math-poly-modulus (math-poly-modulus pn pd))) | |
bf77c646 | 171 | (cdr (math-poly-div pn pd base)))) |
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172 | |
173 | (defun calcFunc-pdivrem (pn pd &optional base) | |
174 | (let* ((calc-prefer-frac t) | |
175 | (math-poly-modulus (math-poly-modulus pn pd)) | |
176 | (res (math-poly-div pn pd base))) | |
bf77c646 | 177 | (list 'vec (car res) (cdr res)))) |
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178 | |
179 | (defun calcFunc-pdivide (pn pd &optional base) | |
180 | (let* ((calc-prefer-frac t) | |
181 | (math-poly-modulus (math-poly-modulus pn pd)) | |
182 | (res (math-poly-div pn pd base))) | |
bf77c646 | 183 | (math-add (car res) (math-div (cdr res) pd)))) |
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184 | |
185 | ||
186 | ;;; Multiply two terms, expanding out products of sums. | |
187 | (defun math-mul-thru (lhs rhs) | |
188 | (if (memq (car-safe lhs) '(+ -)) | |
189 | (list (car lhs) | |
190 | (math-mul-thru (nth 1 lhs) rhs) | |
191 | (math-mul-thru (nth 2 lhs) rhs)) | |
192 | (if (memq (car-safe rhs) '(+ -)) | |
193 | (list (car rhs) | |
194 | (math-mul-thru lhs (nth 1 rhs)) | |
195 | (math-mul-thru lhs (nth 2 rhs))) | |
bf77c646 | 196 | (math-mul lhs rhs)))) |
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197 | |
198 | (defun math-div-thru (num den) | |
199 | (if (memq (car-safe num) '(+ -)) | |
200 | (list (car num) | |
201 | (math-div-thru (nth 1 num) den) | |
202 | (math-div-thru (nth 2 num) den)) | |
bf77c646 | 203 | (math-div num den))) |
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204 | |
205 | ||
206 | ;;; Sort the terms of a sum into canonical order. | |
207 | (defun math-sort-terms (expr) | |
208 | (if (memq (car-safe expr) '(+ -)) | |
209 | (math-list-to-sum | |
210 | (sort (math-sum-to-list expr) | |
211 | (function (lambda (a b) (math-beforep (car a) (car b)))))) | |
bf77c646 | 212 | expr)) |
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213 | |
214 | (defun math-list-to-sum (lst) | |
215 | (if (cdr lst) | |
216 | (list (if (cdr (car lst)) '- '+) | |
217 | (math-list-to-sum (cdr lst)) | |
218 | (car (car lst))) | |
219 | (if (cdr (car lst)) | |
220 | (math-neg (car (car lst))) | |
bf77c646 | 221 | (car (car lst))))) |
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222 | |
223 | (defun math-sum-to-list (tree &optional neg) | |
224 | (cond ((eq (car-safe tree) '+) | |
225 | (nconc (math-sum-to-list (nth 1 tree) neg) | |
226 | (math-sum-to-list (nth 2 tree) neg))) | |
227 | ((eq (car-safe tree) '-) | |
228 | (nconc (math-sum-to-list (nth 1 tree) neg) | |
229 | (math-sum-to-list (nth 2 tree) (not neg)))) | |
bf77c646 | 230 | (t (list (cons tree neg))))) |
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231 | |
232 | ;;; Check if the polynomial coefficients are modulo forms. | |
233 | (defun math-poly-modulus (expr &optional expr2) | |
234 | (or (math-poly-modulus-rec expr) | |
235 | (and expr2 (math-poly-modulus-rec expr2)) | |
bf77c646 | 236 | 1)) |
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237 | |
238 | (defun math-poly-modulus-rec (expr) | |
239 | (if (and (eq (car-safe expr) 'mod) (Math-natnump (nth 2 expr))) | |
240 | (list 'mod 1 (nth 2 expr)) | |
241 | (and (memq (car-safe expr) '(+ - * /)) | |
242 | (or (math-poly-modulus-rec (nth 1 expr)) | |
bf77c646 | 243 | (math-poly-modulus-rec (nth 2 expr)))))) |
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244 | |
245 | ||
246 | ;;; Divide two polynomials. Return (quotient . remainder). | |
3132f345 | 247 | (defvar math-poly-div-base nil) |
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248 | (defun math-poly-div (u v &optional math-poly-div-base) |
249 | (if math-poly-div-base | |
250 | (math-do-poly-div u v) | |
bf77c646 | 251 | (math-do-poly-div (calcFunc-expand u) (calcFunc-expand v)))) |
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252 | |
253 | (defun math-poly-div-exact (u v &optional base) | |
254 | (let ((res (math-poly-div u v base))) | |
255 | (if (eq (cdr res) 0) | |
256 | (car res) | |
bf77c646 | 257 | (math-reject-arg (list 'vec u v) "Argument is not a polynomial")))) |
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258 | |
259 | (defun math-do-poly-div (u v) | |
260 | (cond ((math-constp u) | |
261 | (if (math-constp v) | |
262 | (cons (math-div u v) 0) | |
263 | (cons 0 u))) | |
264 | ((math-constp v) | |
265 | (cons (if (eq v 1) | |
266 | u | |
267 | (if (memq (car-safe u) '(+ -)) | |
268 | (math-add-or-sub (math-poly-div-exact (nth 1 u) v) | |
269 | (math-poly-div-exact (nth 2 u) v) | |
270 | nil (eq (car u) '-)) | |
271 | (math-div u v))) | |
272 | 0)) | |
273 | ((Math-equal u v) | |
274 | (cons math-poly-modulus 0)) | |
275 | ((and (math-atomic-factorp u) (math-atomic-factorp v)) | |
276 | (cons (math-simplify (math-div u v)) 0)) | |
277 | (t | |
278 | (let ((base (or math-poly-div-base | |
279 | (math-poly-div-base u v))) | |
280 | vp up res) | |
281 | (if (or (null base) | |
282 | (null (setq vp (math-is-polynomial v base nil 'gen)))) | |
283 | (cons 0 u) | |
284 | (setq up (math-is-polynomial u base nil 'gen) | |
285 | res (math-poly-div-coefs up vp)) | |
286 | (cons (math-build-polynomial-expr (car res) base) | |
bf77c646 | 287 | (math-build-polynomial-expr (cdr res) base))))))) |
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288 | |
289 | (defun math-poly-div-rec (u v) | |
290 | (cond ((math-constp u) | |
291 | (math-div u v)) | |
292 | ((math-constp v) | |
293 | (if (eq v 1) | |
294 | u | |
295 | (if (memq (car-safe u) '(+ -)) | |
296 | (math-add-or-sub (math-poly-div-rec (nth 1 u) v) | |
297 | (math-poly-div-rec (nth 2 u) v) | |
298 | nil (eq (car u) '-)) | |
299 | (math-div u v)))) | |
300 | ((Math-equal u v) math-poly-modulus) | |
301 | ((and (math-atomic-factorp u) (math-atomic-factorp v)) | |
302 | (math-simplify (math-div u v))) | |
303 | (math-poly-div-base | |
304 | (math-div u v)) | |
305 | (t | |
306 | (let ((base (math-poly-div-base u v)) | |
307 | vp up res) | |
308 | (if (or (null base) | |
309 | (null (setq vp (math-is-polynomial v base nil 'gen)))) | |
310 | (math-div u v) | |
311 | (setq up (math-is-polynomial u base nil 'gen) | |
312 | res (math-poly-div-coefs up vp)) | |
313 | (math-add (math-build-polynomial-expr (car res) base) | |
314 | (math-div (math-build-polynomial-expr (cdr res) base) | |
bf77c646 | 315 | v))))))) |
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316 | |
317 | ;;; Divide two polynomials in coefficient-list form. Return (quot . rem). | |
318 | (defun math-poly-div-coefs (u v) | |
319 | (cond ((null v) (math-reject-arg nil "Division by zero")) | |
320 | ((< (length u) (length v)) (cons nil u)) | |
321 | ((cdr u) | |
322 | (let ((q nil) | |
323 | (urev (reverse u)) | |
324 | (vrev (reverse v))) | |
325 | (while | |
326 | (let ((qk (math-poly-div-rec (math-simplify (car urev)) | |
327 | (car vrev))) | |
328 | (up urev) | |
329 | (vp vrev)) | |
330 | (if (or q (not (math-zerop qk))) | |
331 | (setq q (cons qk q))) | |
332 | (while (setq up (cdr up) vp (cdr vp)) | |
333 | (setcar up (math-sub (car up) (math-mul-thru qk (car vp))))) | |
334 | (setq urev (cdr urev)) | |
335 | up)) | |
336 | (while (and urev (Math-zerop (car urev))) | |
337 | (setq urev (cdr urev))) | |
338 | (cons q (nreverse (mapcar 'math-simplify urev))))) | |
339 | (t | |
340 | (cons (list (math-poly-div-rec (car u) (car v))) | |
bf77c646 | 341 | nil)))) |
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342 | |
343 | ;;; Perform a pseudo-division of polynomials. (See Knuth section 4.6.1.) | |
344 | ;;; This returns only the remainder from the pseudo-division. | |
345 | (defun math-poly-pseudo-div (u v) | |
346 | (cond ((null v) nil) | |
347 | ((< (length u) (length v)) u) | |
348 | ((or (cdr u) (cdr v)) | |
349 | (let ((urev (reverse u)) | |
350 | (vrev (reverse v)) | |
351 | up) | |
352 | (while | |
353 | (let ((vp vrev)) | |
354 | (setq up urev) | |
355 | (while (setq up (cdr up) vp (cdr vp)) | |
356 | (setcar up (math-sub (math-mul-thru (car vrev) (car up)) | |
357 | (math-mul-thru (car urev) (car vp))))) | |
358 | (setq urev (cdr urev)) | |
359 | up) | |
360 | (while up | |
361 | (setcar up (math-mul-thru (car vrev) (car up))) | |
362 | (setq up (cdr up)))) | |
363 | (while (and urev (Math-zerop (car urev))) | |
364 | (setq urev (cdr urev))) | |
365 | (nreverse (mapcar 'math-simplify urev)))) | |
bf77c646 | 366 | (t nil))) |
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367 | |
368 | ;;; Compute the GCD of two multivariate polynomials. | |
369 | (defun math-poly-gcd (u v) | |
370 | (cond ((Math-equal u v) u) | |
371 | ((math-constp u) | |
372 | (if (Math-zerop u) | |
373 | v | |
374 | (calcFunc-gcd u (calcFunc-pcont v)))) | |
375 | ((math-constp v) | |
376 | (if (Math-zerop v) | |
377 | v | |
378 | (calcFunc-gcd v (calcFunc-pcont u)))) | |
379 | (t | |
380 | (let ((base (math-poly-gcd-base u v))) | |
381 | (if base | |
382 | (math-simplify | |
383 | (calcFunc-expand | |
384 | (math-build-polynomial-expr | |
385 | (math-poly-gcd-coefs (math-is-polynomial u base nil 'gen) | |
386 | (math-is-polynomial v base nil 'gen)) | |
387 | base))) | |
bf77c646 | 388 | (calcFunc-gcd (calcFunc-pcont u) (calcFunc-pcont u))))))) |
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389 | |
390 | (defun math-poly-div-list (lst a) | |
391 | (if (eq a 1) | |
392 | lst | |
393 | (if (eq a -1) | |
394 | (math-mul-list lst a) | |
bf77c646 | 395 | (mapcar (function (lambda (x) (math-poly-div-exact x a))) lst)))) |
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396 | |
397 | (defun math-mul-list (lst a) | |
398 | (if (eq a 1) | |
399 | lst | |
400 | (if (eq a -1) | |
401 | (mapcar 'math-neg lst) | |
402 | (and (not (eq a 0)) | |
bf77c646 | 403 | (mapcar (function (lambda (x) (math-mul x a))) lst))))) |
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404 | |
405 | ;;; Run GCD on all elements in a list. | |
406 | (defun math-poly-gcd-list (lst) | |
407 | (if (or (memq 1 lst) (memq -1 lst)) | |
408 | (math-poly-gcd-frac-list lst) | |
409 | (let ((gcd (car lst))) | |
410 | (while (and (setq lst (cdr lst)) (not (eq gcd 1))) | |
411 | (or (eq (car lst) 0) | |
412 | (setq gcd (math-poly-gcd gcd (car lst))))) | |
413 | (if lst (setq lst (math-poly-gcd-frac-list lst))) | |
bf77c646 | 414 | gcd))) |
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415 | |
416 | (defun math-poly-gcd-frac-list (lst) | |
417 | (while (and lst (not (eq (car-safe (car lst)) 'frac))) | |
418 | (setq lst (cdr lst))) | |
419 | (if lst | |
420 | (let ((denom (nth 2 (car lst)))) | |
421 | (while (setq lst (cdr lst)) | |
422 | (if (eq (car-safe (car lst)) 'frac) | |
423 | (setq denom (calcFunc-lcm denom (nth 2 (car lst)))))) | |
424 | (list 'frac 1 denom)) | |
bf77c646 | 425 | 1)) |
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426 | |
427 | ;;; Compute the GCD of two monovariate polynomial lists. | |
428 | ;;; Knuth section 4.6.1, algorithm C. | |
429 | (defun math-poly-gcd-coefs (u v) | |
430 | (let ((d (math-poly-gcd (math-poly-gcd-list u) | |
431 | (math-poly-gcd-list v))) | |
432 | (g 1) (h 1) (z 0) hh r delta ghd) | |
433 | (while (and u v (Math-zerop (car u)) (Math-zerop (car v))) | |
434 | (setq u (cdr u) v (cdr v) z (1+ z))) | |
435 | (or (eq d 1) | |
436 | (setq u (math-poly-div-list u d) | |
437 | v (math-poly-div-list v d))) | |
438 | (while (progn | |
439 | (setq delta (- (length u) (length v))) | |
440 | (if (< delta 0) | |
441 | (setq r u u v v r delta (- delta))) | |
442 | (setq r (math-poly-pseudo-div u v)) | |
443 | (cdr r)) | |
444 | (setq u v | |
445 | v (math-poly-div-list r (math-mul g (math-pow h delta))) | |
446 | g (nth (1- (length u)) u) | |
447 | h (if (<= delta 1) | |
448 | (math-mul (math-pow g delta) (math-pow h (- 1 delta))) | |
449 | (math-poly-div-exact (math-pow g delta) | |
450 | (math-pow h (1- delta)))))) | |
451 | (setq v (if r | |
452 | (list d) | |
453 | (math-mul-list (math-poly-div-list v (math-poly-gcd-list v)) d))) | |
454 | (if (math-guess-if-neg (nth (1- (length v)) v)) | |
455 | (setq v (math-mul-list v -1))) | |
456 | (while (>= (setq z (1- z)) 0) | |
457 | (setq v (cons 0 v))) | |
bf77c646 | 458 | v)) |
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459 | |
460 | ||
461 | ;;; Return true if is a factor containing no sums or quotients. | |
462 | (defun math-atomic-factorp (expr) | |
463 | (cond ((eq (car-safe expr) '*) | |
464 | (and (math-atomic-factorp (nth 1 expr)) | |
465 | (math-atomic-factorp (nth 2 expr)))) | |
466 | ((memq (car-safe expr) '(+ - /)) | |
467 | nil) | |
468 | ((memq (car-safe expr) '(^ neg)) | |
469 | (math-atomic-factorp (nth 1 expr))) | |
bf77c646 | 470 | (t t))) |
136211a9 EZ |
471 | |
472 | ;;; Find a suitable base for dividing a by b. | |
473 | ;;; The base must exist in both expressions. | |
474 | ;;; The degree in the numerator must be higher or equal than the | |
475 | ;;; degree in the denominator. | |
476 | ;;; If the above conditions are not met the quotient is just a remainder. | |
477 | ;;; Return nil if this is the case. | |
478 | ||
479 | (defun math-poly-div-base (a b) | |
480 | (let (a-base b-base) | |
481 | (and (setq a-base (math-total-polynomial-base a)) | |
482 | (setq b-base (math-total-polynomial-base b)) | |
483 | (catch 'return | |
484 | (while a-base | |
485 | (let ((maybe (assoc (car (car a-base)) b-base))) | |
486 | (if maybe | |
487 | (if (>= (nth 1 (car a-base)) (nth 1 maybe)) | |
488 | (throw 'return (car (car a-base)))))) | |
bf77c646 | 489 | (setq a-base (cdr a-base))))))) |
136211a9 EZ |
490 | |
491 | ;;; Same as above but for gcd algorithm. | |
492 | ;;; Here there is no requirement that degree(a) > degree(b). | |
493 | ;;; Take the base that has the highest degree considering both a and b. | |
494 | ;;; ("a^20+b^21+x^3+a+b", "a+b^2+x^5+a^22+b^10") --> (a 22) | |
495 | ||
496 | (defun math-poly-gcd-base (a b) | |
497 | (let (a-base b-base) | |
498 | (and (setq a-base (math-total-polynomial-base a)) | |
499 | (setq b-base (math-total-polynomial-base b)) | |
500 | (catch 'return | |
501 | (while (and a-base b-base) | |
502 | (if (> (nth 1 (car a-base)) (nth 1 (car b-base))) | |
503 | (if (assoc (car (car a-base)) b-base) | |
504 | (throw 'return (car (car a-base))) | |
505 | (setq a-base (cdr a-base))) | |
506 | (if (assoc (car (car b-base)) a-base) | |
507 | (throw 'return (car (car b-base))) | |
bf77c646 | 508 | (setq b-base (cdr b-base))))))))) |
136211a9 EZ |
509 | |
510 | ;;; Sort a list of polynomial bases. | |
511 | (defun math-sort-poly-base-list (lst) | |
512 | (sort lst (function (lambda (a b) | |
513 | (or (> (nth 1 a) (nth 1 b)) | |
514 | (and (= (nth 1 a) (nth 1 b)) | |
bf77c646 | 515 | (math-beforep (car a) (car b)))))))) |
136211a9 EZ |
516 | |
517 | ;;; Given an expression find all variables that are polynomial bases. | |
518 | ;;; Return list in the form '( (var1 degree1) (var2 degree2) ... ). | |
519 | ;;; Note dynamic scope of mpb-total-base. | |
520 | (defun math-total-polynomial-base (expr) | |
521 | (let ((mpb-total-base nil)) | |
522 | (math-polynomial-base expr 'math-polynomial-p1) | |
bf77c646 | 523 | (math-sort-poly-base-list mpb-total-base))) |
136211a9 EZ |
524 | |
525 | (defun math-polynomial-p1 (subexpr) | |
526 | (or (assoc subexpr mpb-total-base) | |
527 | (memq (car subexpr) '(+ - * / neg)) | |
528 | (and (eq (car subexpr) '^) (natnump (nth 2 subexpr))) | |
529 | (let* ((math-poly-base-variable subexpr) | |
530 | (exponent (math-polynomial-p mpb-top-expr subexpr))) | |
531 | (if exponent | |
532 | (setq mpb-total-base (cons (list subexpr exponent) | |
533 | mpb-total-base))))) | |
bf77c646 | 534 | nil) |
136211a9 EZ |
535 | |
536 | ||
537 | ||
538 | ||
539 | (defun calcFunc-factors (expr &optional var) | |
540 | (let ((math-factored-vars (if var t nil)) | |
541 | (math-to-list t) | |
542 | (calc-prefer-frac t)) | |
543 | (or var | |
544 | (setq var (math-polynomial-base expr))) | |
545 | (let ((res (math-factor-finish | |
546 | (or (catch 'factor (math-factor-expr-try var)) | |
547 | expr)))) | |
548 | (math-simplify (if (math-vectorp res) | |
549 | res | |
bf77c646 | 550 | (list 'vec (list 'vec res 1))))))) |
136211a9 EZ |
551 | |
552 | (defun calcFunc-factor (expr &optional var) | |
553 | (let ((math-factored-vars nil) | |
554 | (math-to-list nil) | |
555 | (calc-prefer-frac t)) | |
556 | (math-simplify (math-factor-finish | |
557 | (if var | |
558 | (let ((math-factored-vars t)) | |
559 | (or (catch 'factor (math-factor-expr-try var)) expr)) | |
bf77c646 | 560 | (math-factor-expr expr)))))) |
136211a9 EZ |
561 | |
562 | (defun math-factor-finish (x) | |
563 | (if (Math-primp x) | |
564 | x | |
565 | (if (eq (car x) 'calcFunc-Fac-Prot) | |
566 | (math-factor-finish (nth 1 x)) | |
bf77c646 | 567 | (cons (car x) (mapcar 'math-factor-finish (cdr x)))))) |
136211a9 EZ |
568 | |
569 | (defun math-factor-protect (x) | |
570 | (if (memq (car-safe x) '(+ -)) | |
571 | (list 'calcFunc-Fac-Prot x) | |
bf77c646 | 572 | x)) |
136211a9 EZ |
573 | |
574 | (defun math-factor-expr (expr) | |
575 | (cond ((eq math-factored-vars t) expr) | |
576 | ((or (memq (car-safe expr) '(* / ^ neg)) | |
577 | (assq (car-safe expr) calc-tweak-eqn-table)) | |
578 | (cons (car expr) (mapcar 'math-factor-expr (cdr expr)))) | |
579 | ((memq (car-safe expr) '(+ -)) | |
580 | (let* ((math-factored-vars math-factored-vars) | |
581 | (y (catch 'factor (math-factor-expr-part expr)))) | |
582 | (if y | |
583 | (math-factor-expr y) | |
584 | expr))) | |
bf77c646 | 585 | (t expr))) |
136211a9 EZ |
586 | |
587 | (defun math-factor-expr-part (x) ; uses "expr" | |
588 | (if (memq (car-safe x) '(+ - * / ^ neg)) | |
589 | (while (setq x (cdr x)) | |
590 | (math-factor-expr-part (car x))) | |
591 | (and (not (Math-objvecp x)) | |
592 | (not (assoc x math-factored-vars)) | |
593 | (> (math-factor-contains expr x) 1) | |
594 | (setq math-factored-vars (cons (list x) math-factored-vars)) | |
bf77c646 | 595 | (math-factor-expr-try x)))) |
136211a9 EZ |
596 | |
597 | (defun math-factor-expr-try (x) | |
598 | (if (eq (car-safe expr) '*) | |
599 | (let ((res1 (catch 'factor (let ((expr (nth 1 expr))) | |
600 | (math-factor-expr-try x)))) | |
601 | (res2 (catch 'factor (let ((expr (nth 2 expr))) | |
602 | (math-factor-expr-try x))))) | |
603 | (and (or res1 res2) | |
604 | (throw 'factor (math-accum-factors (or res1 (nth 1 expr)) 1 | |
605 | (or res2 (nth 2 expr)))))) | |
606 | (let* ((p (math-is-polynomial expr x 30 'gen)) | |
607 | (math-poly-modulus (math-poly-modulus expr)) | |
608 | res) | |
609 | (and (cdr p) | |
610 | (setq res (math-factor-poly-coefs p)) | |
bf77c646 | 611 | (throw 'factor res))))) |
136211a9 EZ |
612 | |
613 | (defun math-accum-factors (fac pow facs) | |
614 | (if math-to-list | |
615 | (if (math-vectorp fac) | |
616 | (progn | |
617 | (while (setq fac (cdr fac)) | |
618 | (setq facs (math-accum-factors (nth 1 (car fac)) | |
619 | (* pow (nth 2 (car fac))) | |
620 | facs))) | |
621 | facs) | |
622 | (if (and (eq (car-safe fac) '^) (natnump (nth 2 fac))) | |
623 | (setq pow (* pow (nth 2 fac)) | |
624 | fac (nth 1 fac))) | |
625 | (if (eq fac 1) | |
626 | facs | |
627 | (or (math-vectorp facs) | |
628 | (setq facs (if (eq facs 1) '(vec) | |
629 | (list 'vec (list 'vec facs 1))))) | |
630 | (let ((found facs)) | |
631 | (while (and (setq found (cdr found)) | |
632 | (not (equal fac (nth 1 (car found)))))) | |
633 | (if found | |
634 | (progn | |
635 | (setcar (cdr (cdr (car found))) (+ pow (nth 2 (car found)))) | |
636 | facs) | |
637 | ;; Put constant term first. | |
638 | (if (and (cdr facs) (Math-ratp (nth 1 (nth 1 facs)))) | |
639 | (cons 'vec (cons (nth 1 facs) (cons (list 'vec fac pow) | |
640 | (cdr (cdr facs))))) | |
641 | (cons 'vec (cons (list 'vec fac pow) (cdr facs)))))))) | |
bf77c646 | 642 | (math-mul (math-pow fac pow) facs))) |
136211a9 EZ |
643 | |
644 | (defun math-factor-poly-coefs (p &optional square-free) ; uses "x" | |
645 | (let (t1 t2) | |
646 | (cond ((not (cdr p)) | |
647 | (or (car p) 0)) | |
648 | ||
649 | ;; Strip off multiples of x. | |
650 | ((Math-zerop (car p)) | |
651 | (let ((z 0)) | |
652 | (while (and p (Math-zerop (car p))) | |
653 | (setq z (1+ z) p (cdr p))) | |
654 | (if (cdr p) | |
655 | (setq p (math-factor-poly-coefs p square-free)) | |
656 | (setq p (math-sort-terms (math-factor-expr (car p))))) | |
657 | (math-accum-factors x z (math-factor-protect p)))) | |
658 | ||
659 | ;; Factor out content. | |
660 | ((and (not square-free) | |
661 | (not (eq 1 (setq t1 (math-mul (math-poly-gcd-list p) | |
662 | (if (math-guess-if-neg | |
663 | (nth (1- (length p)) p)) | |
664 | -1 1)))))) | |
665 | (math-accum-factors t1 1 (math-factor-poly-coefs | |
666 | (math-poly-div-list p t1) 'cont))) | |
667 | ||
668 | ;; Check if linear in x. | |
669 | ((not (cdr (cdr p))) | |
670 | (math-add (math-factor-protect | |
671 | (math-sort-terms | |
672 | (math-factor-expr (car p)))) | |
673 | (math-mul x (math-factor-protect | |
674 | (math-sort-terms | |
675 | (math-factor-expr (nth 1 p))))))) | |
676 | ||
677 | ;; If symbolic coefficients, use FactorRules. | |
678 | ((let ((pp p)) | |
679 | (while (and pp (or (Math-ratp (car pp)) | |
680 | (and (eq (car (car pp)) 'mod) | |
681 | (Math-integerp (nth 1 (car pp))) | |
682 | (Math-integerp (nth 2 (car pp)))))) | |
683 | (setq pp (cdr pp))) | |
684 | pp) | |
685 | (let ((res (math-rewrite | |
686 | (list 'calcFunc-thecoefs x (cons 'vec p)) | |
687 | '(var FactorRules var-FactorRules)))) | |
688 | (or (and (eq (car-safe res) 'calcFunc-thefactors) | |
689 | (= (length res) 3) | |
690 | (math-vectorp (nth 2 res)) | |
691 | (let ((facs 1) | |
692 | (vec (nth 2 res))) | |
693 | (while (setq vec (cdr vec)) | |
694 | (setq facs (math-accum-factors (car vec) 1 facs))) | |
695 | facs)) | |
696 | (math-build-polynomial-expr p x)))) | |
697 | ||
698 | ;; Check if rational coefficients (i.e., not modulo a prime). | |
699 | ((eq math-poly-modulus 1) | |
700 | ||
701 | ;; Check if there are any squared terms, or a content not = 1. | |
702 | (if (or (eq square-free t) | |
703 | (equal (setq t1 (math-poly-gcd-coefs | |
704 | p (setq t2 (math-poly-deriv-coefs p)))) | |
705 | '(1))) | |
706 | ||
707 | ;; We now have a square-free polynomial with integer coefs. | |
708 | ;; For now, we use a kludgey method that finds linear and | |
709 | ;; quadratic terms using floating-point root-finding. | |
710 | (if (setq t1 (let ((calc-symbolic-mode nil)) | |
711 | (math-poly-all-roots nil p t))) | |
712 | (let ((roots (car t1)) | |
713 | (csign (if (math-negp (nth (1- (length p)) p)) -1 1)) | |
714 | (expr 1) | |
715 | (unfac (nth 1 t1)) | |
716 | (scale (nth 2 t1))) | |
717 | (while roots | |
718 | (let ((coef0 (car (car roots))) | |
719 | (coef1 (cdr (car roots)))) | |
720 | (setq expr (math-accum-factors | |
721 | (if coef1 | |
722 | (let ((den (math-lcm-denoms | |
723 | coef0 coef1))) | |
724 | (setq scale (math-div scale den)) | |
725 | (math-add | |
726 | (math-add | |
727 | (math-mul den (math-pow x 2)) | |
728 | (math-mul (math-mul coef1 den) x)) | |
729 | (math-mul coef0 den))) | |
730 | (let ((den (math-lcm-denoms coef0))) | |
731 | (setq scale (math-div scale den)) | |
732 | (math-add (math-mul den x) | |
733 | (math-mul coef0 den)))) | |
734 | 1 expr) | |
735 | roots (cdr roots)))) | |
736 | (setq expr (math-accum-factors | |
737 | expr 1 | |
738 | (math-mul csign | |
739 | (math-build-polynomial-expr | |
740 | (math-mul-list (nth 1 t1) scale) | |
741 | x))))) | |
742 | (math-build-polynomial-expr p x)) ; can't factor it. | |
743 | ||
744 | ;; Separate out the squared terms (Knuth exercise 4.6.2-34). | |
745 | ;; This step also divides out the content of the polynomial. | |
746 | (let* ((cabs (math-poly-gcd-list p)) | |
747 | (csign (if (math-negp (nth (1- (length p)) p)) -1 1)) | |
748 | (t1s (math-mul-list t1 csign)) | |
749 | (uu nil) | |
750 | (v (car (math-poly-div-coefs p t1s))) | |
751 | (w (car (math-poly-div-coefs t2 t1s)))) | |
752 | (while | |
753 | (not (math-poly-zerop | |
754 | (setq t2 (math-poly-simplify | |
755 | (math-poly-mix | |
756 | w 1 (math-poly-deriv-coefs v) -1))))) | |
757 | (setq t1 (math-poly-gcd-coefs v t2) | |
758 | uu (cons t1 uu) | |
759 | v (car (math-poly-div-coefs v t1)) | |
760 | w (car (math-poly-div-coefs t2 t1)))) | |
761 | (setq t1 (length uu) | |
762 | t2 (math-accum-factors (math-factor-poly-coefs v t) | |
763 | (1+ t1) 1)) | |
764 | (while uu | |
765 | (setq t2 (math-accum-factors (math-factor-poly-coefs | |
766 | (car uu) t) | |
767 | t1 t2) | |
768 | t1 (1- t1) | |
769 | uu (cdr uu))) | |
770 | (math-accum-factors (math-mul cabs csign) 1 t2)))) | |
771 | ||
772 | ;; Factoring modulo a prime. | |
773 | ((and (= (length (setq temp (math-poly-gcd-coefs | |
774 | p (math-poly-deriv-coefs p)))) | |
775 | (length p))) | |
776 | (setq p (car temp)) | |
777 | (while (cdr temp) | |
778 | (setq temp (nthcdr (nth 2 math-poly-modulus) temp) | |
779 | p (cons (car temp) p))) | |
780 | (and (setq temp (math-factor-poly-coefs p)) | |
781 | (math-pow temp (nth 2 math-poly-modulus)))) | |
782 | (t | |
bf77c646 | 783 | (math-reject-arg nil "*Modulo factorization not yet implemented"))))) |
136211a9 EZ |
784 | |
785 | (defun math-poly-deriv-coefs (p) | |
786 | (let ((n 1) | |
787 | (dp nil)) | |
788 | (while (setq p (cdr p)) | |
789 | (setq dp (cons (math-mul (car p) n) dp) | |
790 | n (1+ n))) | |
bf77c646 | 791 | (nreverse dp))) |
136211a9 EZ |
792 | |
793 | (defun math-factor-contains (x a) | |
794 | (if (equal x a) | |
795 | 1 | |
796 | (if (memq (car-safe x) '(+ - * / neg)) | |
797 | (let ((sum 0)) | |
798 | (while (setq x (cdr x)) | |
799 | (setq sum (+ sum (math-factor-contains (car x) a)))) | |
800 | sum) | |
801 | (if (and (eq (car-safe x) '^) | |
802 | (natnump (nth 2 x))) | |
803 | (* (math-factor-contains (nth 1 x) a) (nth 2 x)) | |
bf77c646 | 804 | 0)))) |
136211a9 EZ |
805 | |
806 | ||
807 | ||
808 | ||
809 | ||
810 | ;;; Merge all quotients and expand/simplify the numerator | |
811 | (defun calcFunc-nrat (expr) | |
812 | (if (math-any-floats expr) | |
813 | (setq expr (calcFunc-pfrac expr))) | |
814 | (if (or (math-vectorp expr) | |
815 | (assq (car-safe expr) calc-tweak-eqn-table)) | |
816 | (cons (car expr) (mapcar 'calcFunc-nrat (cdr expr))) | |
817 | (let* ((calc-prefer-frac t) | |
818 | (res (math-to-ratpoly expr)) | |
819 | (num (math-simplify (math-sort-terms (calcFunc-expand (car res))))) | |
820 | (den (math-simplify (math-sort-terms (calcFunc-expand (cdr res))))) | |
821 | (g (math-poly-gcd num den))) | |
822 | (or (eq g 1) | |
823 | (let ((num2 (math-poly-div num g)) | |
824 | (den2 (math-poly-div den g))) | |
825 | (and (eq (cdr num2) 0) (eq (cdr den2) 0) | |
826 | (setq num (car num2) den (car den2))))) | |
bf77c646 | 827 | (math-simplify (math-div num den))))) |
136211a9 EZ |
828 | |
829 | ;;; Returns expressions (num . denom). | |
830 | (defun math-to-ratpoly (expr) | |
831 | (let ((res (math-to-ratpoly-rec expr))) | |
bf77c646 | 832 | (cons (math-simplify (car res)) (math-simplify (cdr res))))) |
136211a9 EZ |
833 | |
834 | (defun math-to-ratpoly-rec (expr) | |
835 | (cond ((Math-primp expr) | |
836 | (cons expr 1)) | |
837 | ((memq (car expr) '(+ -)) | |
838 | (let ((r1 (math-to-ratpoly-rec (nth 1 expr))) | |
839 | (r2 (math-to-ratpoly-rec (nth 2 expr)))) | |
840 | (if (equal (cdr r1) (cdr r2)) | |
841 | (cons (list (car expr) (car r1) (car r2)) (cdr r1)) | |
842 | (if (eq (cdr r1) 1) | |
843 | (cons (list (car expr) | |
844 | (math-mul (car r1) (cdr r2)) | |
845 | (car r2)) | |
846 | (cdr r2)) | |
847 | (if (eq (cdr r2) 1) | |
848 | (cons (list (car expr) | |
849 | (car r1) | |
850 | (math-mul (car r2) (cdr r1))) | |
851 | (cdr r1)) | |
852 | (let ((g (math-poly-gcd (cdr r1) (cdr r2)))) | |
853 | (let ((d1 (and (not (eq g 1)) (math-poly-div (cdr r1) g))) | |
854 | (d2 (and (not (eq g 1)) (math-poly-div | |
855 | (math-mul (car r1) (cdr r2)) | |
856 | g)))) | |
857 | (if (and (eq (cdr d1) 0) (eq (cdr d2) 0)) | |
858 | (cons (list (car expr) (car d2) | |
859 | (math-mul (car r2) (car d1))) | |
860 | (math-mul (car d1) (cdr r2))) | |
861 | (cons (list (car expr) | |
862 | (math-mul (car r1) (cdr r2)) | |
863 | (math-mul (car r2) (cdr r1))) | |
864 | (math-mul (cdr r1) (cdr r2))))))))))) | |
865 | ((eq (car expr) '*) | |
866 | (let* ((r1 (math-to-ratpoly-rec (nth 1 expr))) | |
867 | (r2 (math-to-ratpoly-rec (nth 2 expr))) | |
868 | (g (math-mul (math-poly-gcd (car r1) (cdr r2)) | |
869 | (math-poly-gcd (cdr r1) (car r2))))) | |
870 | (if (eq g 1) | |
871 | (cons (math-mul (car r1) (car r2)) | |
872 | (math-mul (cdr r1) (cdr r2))) | |
873 | (cons (math-poly-div-exact (math-mul (car r1) (car r2)) g) | |
874 | (math-poly-div-exact (math-mul (cdr r1) (cdr r2)) g))))) | |
875 | ((eq (car expr) '/) | |
876 | (let* ((r1 (math-to-ratpoly-rec (nth 1 expr))) | |
877 | (r2 (math-to-ratpoly-rec (nth 2 expr)))) | |
878 | (if (and (eq (cdr r1) 1) (eq (cdr r2) 1)) | |
879 | (cons (car r1) (car r2)) | |
880 | (let ((g (math-mul (math-poly-gcd (car r1) (car r2)) | |
881 | (math-poly-gcd (cdr r1) (cdr r2))))) | |
882 | (if (eq g 1) | |
883 | (cons (math-mul (car r1) (cdr r2)) | |
884 | (math-mul (cdr r1) (car r2))) | |
885 | (cons (math-poly-div-exact (math-mul (car r1) (cdr r2)) g) | |
886 | (math-poly-div-exact (math-mul (cdr r1) (car r2)) | |
887 | g))))))) | |
888 | ((and (eq (car expr) '^) (integerp (nth 2 expr))) | |
889 | (let ((r1 (math-to-ratpoly-rec (nth 1 expr)))) | |
890 | (if (> (nth 2 expr) 0) | |
891 | (cons (math-pow (car r1) (nth 2 expr)) | |
892 | (math-pow (cdr r1) (nth 2 expr))) | |
893 | (cons (math-pow (cdr r1) (- (nth 2 expr))) | |
894 | (math-pow (car r1) (- (nth 2 expr))))))) | |
895 | ((eq (car expr) 'neg) | |
896 | (let ((r1 (math-to-ratpoly-rec (nth 1 expr)))) | |
897 | (cons (math-neg (car r1)) (cdr r1)))) | |
bf77c646 | 898 | (t (cons expr 1)))) |
136211a9 EZ |
899 | |
900 | ||
901 | (defun math-ratpoly-p (expr &optional var) | |
902 | (cond ((equal expr var) 1) | |
903 | ((Math-primp expr) 0) | |
904 | ((memq (car expr) '(+ -)) | |
905 | (let ((p1 (math-ratpoly-p (nth 1 expr) var)) | |
906 | p2) | |
907 | (and p1 (setq p2 (math-ratpoly-p (nth 2 expr) var)) | |
908 | (max p1 p2)))) | |
909 | ((eq (car expr) '*) | |
910 | (let ((p1 (math-ratpoly-p (nth 1 expr) var)) | |
911 | p2) | |
912 | (and p1 (setq p2 (math-ratpoly-p (nth 2 expr) var)) | |
913 | (+ p1 p2)))) | |
914 | ((eq (car expr) 'neg) | |
915 | (math-ratpoly-p (nth 1 expr) var)) | |
916 | ((eq (car expr) '/) | |
917 | (let ((p1 (math-ratpoly-p (nth 1 expr) var)) | |
918 | p2) | |
919 | (and p1 (setq p2 (math-ratpoly-p (nth 2 expr) var)) | |
920 | (- p1 p2)))) | |
921 | ((and (eq (car expr) '^) | |
922 | (integerp (nth 2 expr))) | |
923 | (let ((p1 (math-ratpoly-p (nth 1 expr) var))) | |
924 | (and p1 (* p1 (nth 2 expr))))) | |
925 | ((not var) 1) | |
926 | ((math-poly-depends expr var) nil) | |
bf77c646 | 927 | (t 0))) |
136211a9 EZ |
928 | |
929 | ||
930 | (defun calcFunc-apart (expr &optional var) | |
931 | (cond ((Math-primp expr) expr) | |
932 | ((eq (car expr) '+) | |
933 | (math-add (calcFunc-apart (nth 1 expr) var) | |
934 | (calcFunc-apart (nth 2 expr) var))) | |
935 | ((eq (car expr) '-) | |
936 | (math-sub (calcFunc-apart (nth 1 expr) var) | |
937 | (calcFunc-apart (nth 2 expr) var))) | |
938 | ((not (math-ratpoly-p expr var)) | |
939 | (math-reject-arg expr "Expected a rational function")) | |
940 | (t | |
941 | (let* ((calc-prefer-frac t) | |
942 | (rat (math-to-ratpoly expr)) | |
943 | (num (car rat)) | |
944 | (den (cdr rat)) | |
945 | (qr (math-poly-div num den)) | |
946 | (q (car qr)) | |
947 | (r (cdr qr))) | |
948 | (or var | |
949 | (setq var (math-polynomial-base den))) | |
950 | (math-add q (or (and var | |
951 | (math-expr-contains den var) | |
952 | (math-partial-fractions r den var)) | |
bf77c646 | 953 | (math-div r den))))))) |
136211a9 EZ |
954 | |
955 | ||
956 | (defun math-padded-polynomial (expr var deg) | |
957 | (let ((p (math-is-polynomial expr var deg))) | |
bf77c646 | 958 | (append p (make-list (- deg (length p)) 0)))) |
136211a9 EZ |
959 | |
960 | (defun math-partial-fractions (r den var) | |
961 | (let* ((fden (calcFunc-factors den var)) | |
962 | (tdeg (math-polynomial-p den var)) | |
963 | (fp fden) | |
964 | (dlist nil) | |
965 | (eqns 0) | |
966 | (lz nil) | |
967 | (tz (make-list (1- tdeg) 0)) | |
968 | (calc-matrix-mode 'scalar)) | |
969 | (and (not (and (= (length fden) 2) (eq (nth 2 (nth 1 fden)) 1))) | |
970 | (progn | |
971 | (while (setq fp (cdr fp)) | |
972 | (let ((rpt (nth 2 (car fp))) | |
973 | (deg (math-polynomial-p (nth 1 (car fp)) var)) | |
974 | dnum dvar deg2) | |
975 | (while (> rpt 0) | |
976 | (setq deg2 deg | |
977 | dnum 0) | |
978 | (while (> deg2 0) | |
979 | (setq dvar (append '(vec) lz '(1) tz) | |
980 | lz (cons 0 lz) | |
981 | tz (cdr tz) | |
982 | deg2 (1- deg2) | |
983 | dnum (math-add dnum (math-mul dvar | |
984 | (math-pow var deg2))) | |
985 | dlist (cons (and (= deg2 (1- deg)) | |
986 | (math-pow (nth 1 (car fp)) rpt)) | |
987 | dlist))) | |
988 | (let ((fpp fden) | |
989 | (mult 1)) | |
990 | (while (setq fpp (cdr fpp)) | |
991 | (or (eq fpp fp) | |
992 | (setq mult (math-mul mult | |
993 | (math-pow (nth 1 (car fpp)) | |
994 | (nth 2 (car fpp))))))) | |
995 | (setq dnum (math-mul dnum mult))) | |
996 | (setq eqns (math-add eqns (math-mul dnum | |
997 | (math-pow | |
998 | (nth 1 (car fp)) | |
999 | (- (nth 2 (car fp)) | |
1000 | rpt)))) | |
1001 | rpt (1- rpt))))) | |
1002 | (setq eqns (math-div (cons 'vec (math-padded-polynomial r var tdeg)) | |
1003 | (math-transpose | |
1004 | (cons 'vec | |
1005 | (mapcar | |
1006 | (function | |
1007 | (lambda (x) | |
1008 | (cons 'vec (math-padded-polynomial | |
1009 | x var tdeg)))) | |
1010 | (cdr eqns)))))) | |
1011 | (and (math-vectorp eqns) | |
1012 | (let ((res 0) | |
1013 | (num nil)) | |
1014 | (setq eqns (nreverse eqns)) | |
1015 | (while eqns | |
1016 | (setq num (cons (car eqns) num) | |
1017 | eqns (cdr eqns)) | |
1018 | (if (car dlist) | |
1019 | (setq num (math-build-polynomial-expr | |
1020 | (nreverse num) var) | |
1021 | res (math-add res (math-div num (car dlist))) | |
1022 | num nil)) | |
1023 | (setq dlist (cdr dlist))) | |
bf77c646 | 1024 | (math-normalize res))))))) |
136211a9 EZ |
1025 | |
1026 | ||
1027 | ||
1028 | (defun math-expand-term (expr) | |
1029 | (cond ((and (eq (car-safe expr) '*) | |
1030 | (memq (car-safe (nth 1 expr)) '(+ -))) | |
1031 | (math-add-or-sub (list '* (nth 1 (nth 1 expr)) (nth 2 expr)) | |
1032 | (list '* (nth 2 (nth 1 expr)) (nth 2 expr)) | |
1033 | nil (eq (car (nth 1 expr)) '-))) | |
1034 | ((and (eq (car-safe expr) '*) | |
1035 | (memq (car-safe (nth 2 expr)) '(+ -))) | |
1036 | (math-add-or-sub (list '* (nth 1 expr) (nth 1 (nth 2 expr))) | |
1037 | (list '* (nth 1 expr) (nth 2 (nth 2 expr))) | |
1038 | nil (eq (car (nth 2 expr)) '-))) | |
1039 | ((and (eq (car-safe expr) '/) | |
1040 | (memq (car-safe (nth 1 expr)) '(+ -))) | |
1041 | (math-add-or-sub (list '/ (nth 1 (nth 1 expr)) (nth 2 expr)) | |
1042 | (list '/ (nth 2 (nth 1 expr)) (nth 2 expr)) | |
1043 | nil (eq (car (nth 1 expr)) '-))) | |
1044 | ((and (eq (car-safe expr) '^) | |
1045 | (memq (car-safe (nth 1 expr)) '(+ -)) | |
1046 | (integerp (nth 2 expr)) | |
1047 | (if (> (nth 2 expr) 0) | |
f7917133 | 1048 | (or (and (or (> math-mt-many 500000) (< math-mt-many -500000)) |
136211a9 EZ |
1049 | (math-expand-power (nth 1 expr) (nth 2 expr) |
1050 | nil t)) | |
1051 | (list '* | |
1052 | (nth 1 expr) | |
1053 | (list '^ (nth 1 expr) (1- (nth 2 expr))))) | |
1054 | (if (< (nth 2 expr) 0) | |
1055 | (list '/ 1 (list '^ (nth 1 expr) (- (nth 2 expr)))))))) | |
bf77c646 | 1056 | (t expr))) |
136211a9 EZ |
1057 | |
1058 | (defun calcFunc-expand (expr &optional many) | |
bf77c646 | 1059 | (math-normalize (math-map-tree 'math-expand-term expr many))) |
136211a9 EZ |
1060 | |
1061 | (defun math-expand-power (x n &optional var else-nil) | |
1062 | (or (and (natnump n) | |
1063 | (memq (car-safe x) '(+ -)) | |
1064 | (let ((terms nil) | |
1065 | (cterms nil)) | |
1066 | (while (memq (car-safe x) '(+ -)) | |
1067 | (setq terms (cons (if (eq (car x) '-) | |
1068 | (math-neg (nth 2 x)) | |
1069 | (nth 2 x)) | |
1070 | terms) | |
1071 | x (nth 1 x))) | |
1072 | (setq terms (cons x terms)) | |
1073 | (if var | |
1074 | (let ((p terms)) | |
1075 | (while p | |
1076 | (or (math-expr-contains (car p) var) | |
1077 | (setq terms (delq (car p) terms) | |
1078 | cterms (cons (car p) cterms))) | |
1079 | (setq p (cdr p))) | |
1080 | (if cterms | |
1081 | (setq terms (cons (apply 'calcFunc-add cterms) | |
1082 | terms))))) | |
1083 | (if (= (length terms) 2) | |
1084 | (let ((i 0) | |
1085 | (accum 0)) | |
1086 | (while (<= i n) | |
1087 | (setq accum (list '+ accum | |
1088 | (list '* (calcFunc-choose n i) | |
1089 | (list '* | |
1090 | (list '^ (nth 1 terms) i) | |
1091 | (list '^ (car terms) | |
1092 | (- n i))))) | |
1093 | i (1+ i))) | |
1094 | accum) | |
1095 | (if (= n 2) | |
1096 | (let ((accum 0) | |
1097 | (p1 terms) | |
1098 | p2) | |
1099 | (while p1 | |
1100 | (setq accum (list '+ accum | |
1101 | (list '^ (car p1) 2)) | |
1102 | p2 p1) | |
1103 | (while (setq p2 (cdr p2)) | |
1104 | (setq accum (list '+ accum | |
1105 | (list '* 2 (list '* | |
1106 | (car p1) | |
1107 | (car p2)))))) | |
1108 | (setq p1 (cdr p1))) | |
1109 | accum) | |
1110 | (if (= n 3) | |
1111 | (let ((accum 0) | |
1112 | (p1 terms) | |
1113 | p2 p3) | |
1114 | (while p1 | |
1115 | (setq accum (list '+ accum (list '^ (car p1) 3)) | |
1116 | p2 p1) | |
1117 | (while (setq p2 (cdr p2)) | |
1118 | (setq accum (list '+ | |
1119 | (list '+ | |
1120 | accum | |
1121 | (list '* 3 | |
1122 | (list | |
1123 | '* | |
1124 | (list '^ (car p1) 2) | |
1125 | (car p2)))) | |
1126 | (list '* 3 | |
1127 | (list | |
1128 | '* (car p1) | |
1129 | (list '^ (car p2) 2)))) | |
1130 | p3 p2) | |
1131 | (while (setq p3 (cdr p3)) | |
1132 | (setq accum (list '+ accum | |
1133 | (list '* 6 | |
1134 | (list '* | |
1135 | (car p1) | |
1136 | (list | |
1137 | '* (car p2) | |
1138 | (car p3)))))))) | |
1139 | (setq p1 (cdr p1))) | |
1140 | accum)))))) | |
1141 | (and (not else-nil) | |
bf77c646 | 1142 | (list '^ x n)))) |
136211a9 EZ |
1143 | |
1144 | (defun calcFunc-expandpow (x n) | |
bf77c646 | 1145 | (math-normalize (math-expand-power x n))) |
136211a9 | 1146 | |
ab5796a9 | 1147 | ;;; arch-tag: d2566c51-2ccc-45f1-8c50-f3462c2953ff |
bf77c646 | 1148 | ;;; calc-poly.el ends here |