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[bpt/emacs.git] / lisp / calc / calc-alg.el
1 ;;; calc-alg.el --- algebraic functions for Calc
2
3 ;; Copyright (C) 1990, 1991, 1992, 1993, 2001, 2005 Free Software Foundation, Inc.
4
5 ;; Author: David Gillespie <daveg@synaptics.com>
6 ;; Maintainer: Jay Belanger <belanger@truman.edu>
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
25 ;;; Commentary:
26
27 ;;; Code:
28
29 ;; This file is autoloaded from calc-ext.el.
30
31 (require 'calc-ext)
32 (require 'calc-macs)
33
34 ;;; Algebra commands.
35
36 (defun calc-alg-evaluate (arg)
37 (interactive "p")
38 (calc-slow-wrapper
39 (calc-with-default-simplification
40 (let ((math-simplify-only nil))
41 (calc-modify-simplify-mode arg)
42 (calc-enter-result 1 "dsmp" (calc-top 1))))))
43
44 (defun calc-modify-simplify-mode (arg)
45 (if (= (math-abs arg) 2)
46 (setq calc-simplify-mode 'alg)
47 (if (>= (math-abs arg) 3)
48 (setq calc-simplify-mode 'ext)))
49 (if (< arg 0)
50 (setq calc-simplify-mode (list calc-simplify-mode))))
51
52 (defun calc-simplify ()
53 (interactive)
54 (calc-slow-wrapper
55 (calc-with-default-simplification
56 (calc-enter-result 1 "simp" (math-simplify (calc-top-n 1))))))
57
58 (defun calc-simplify-extended ()
59 (interactive)
60 (calc-slow-wrapper
61 (calc-with-default-simplification
62 (calc-enter-result 1 "esmp" (math-simplify-extended (calc-top-n 1))))))
63
64 (defun calc-expand-formula (arg)
65 (interactive "p")
66 (calc-slow-wrapper
67 (calc-with-default-simplification
68 (let ((math-simplify-only nil))
69 (calc-modify-simplify-mode arg)
70 (calc-enter-result 1 "expf"
71 (if (> arg 0)
72 (let ((math-expand-formulas t))
73 (calc-top-n 1))
74 (let ((top (calc-top-n 1)))
75 (or (math-expand-formula top)
76 top))))))))
77
78 (defun calc-factor (arg)
79 (interactive "P")
80 (calc-slow-wrapper
81 (calc-unary-op "fctr" (if (calc-is-hyperbolic)
82 'calcFunc-factors 'calcFunc-factor)
83 arg)))
84
85 (defun calc-expand (n)
86 (interactive "P")
87 (calc-slow-wrapper
88 (calc-enter-result 1 "expa"
89 (append (list 'calcFunc-expand
90 (calc-top-n 1))
91 (and n (list (prefix-numeric-value n)))))))
92
93 (defun calc-collect (&optional var)
94 (interactive "sCollect terms involving: ")
95 (calc-slow-wrapper
96 (if (or (equal var "") (equal var "$") (null var))
97 (calc-enter-result 2 "clct" (cons 'calcFunc-collect
98 (calc-top-list-n 2)))
99 (let ((var (math-read-expr var)))
100 (if (eq (car-safe var) 'error)
101 (error "Bad format in expression: %s" (nth 1 var)))
102 (calc-enter-result 1 "clct" (list 'calcFunc-collect
103 (calc-top-n 1)
104 var))))))
105
106 (defun calc-apart (arg)
107 (interactive "P")
108 (calc-slow-wrapper
109 (calc-unary-op "aprt" 'calcFunc-apart arg)))
110
111 (defun calc-normalize-rat (arg)
112 (interactive "P")
113 (calc-slow-wrapper
114 (calc-unary-op "nrat" 'calcFunc-nrat arg)))
115
116 (defun calc-poly-gcd (arg)
117 (interactive "P")
118 (calc-slow-wrapper
119 (calc-binary-op "pgcd" 'calcFunc-pgcd arg)))
120
121
122 (defun calc-poly-div (arg)
123 (interactive "P")
124 (calc-slow-wrapper
125 (let ((calc-poly-div-remainder nil))
126 (calc-binary-op "pdiv" 'calcFunc-pdiv arg)
127 (if (and calc-poly-div-remainder (null arg))
128 (progn
129 (calc-clear-command-flag 'clear-message)
130 (calc-record calc-poly-div-remainder "prem")
131 (if (not (Math-zerop calc-poly-div-remainder))
132 (message "(Remainder was %s)"
133 (math-format-flat-expr calc-poly-div-remainder 0))
134 (message "(No remainder)")))))))
135
136 (defun calc-poly-rem (arg)
137 (interactive "P")
138 (calc-slow-wrapper
139 (calc-binary-op "prem" 'calcFunc-prem arg)))
140
141 (defun calc-poly-div-rem (arg)
142 (interactive "P")
143 (calc-slow-wrapper
144 (if (calc-is-hyperbolic)
145 (calc-binary-op "pdvr" 'calcFunc-pdivide arg)
146 (calc-binary-op "pdvr" 'calcFunc-pdivrem arg))))
147
148 (defun calc-substitute (&optional oldname newname)
149 (interactive "sSubstitute old: ")
150 (calc-slow-wrapper
151 (let (old new (num 1) expr)
152 (if (or (equal oldname "") (equal oldname "$") (null oldname))
153 (setq new (calc-top-n 1)
154 old (calc-top-n 2)
155 expr (calc-top-n 3)
156 num 3)
157 (or newname
158 (progn (calc-unread-command ?\C-a)
159 (setq newname (read-string (concat "Substitute old: "
160 oldname
161 ", new: ")
162 oldname))))
163 (if (or (equal newname "") (equal newname "$") (null newname))
164 (setq new (calc-top-n 1)
165 expr (calc-top-n 2)
166 num 2)
167 (setq new (if (stringp newname) (math-read-expr newname) newname))
168 (if (eq (car-safe new) 'error)
169 (error "Bad format in expression: %s" (nth 1 new)))
170 (setq expr (calc-top-n 1)))
171 (setq old (if (stringp oldname) (math-read-expr oldname) oldname))
172 (if (eq (car-safe old) 'error)
173 (error "Bad format in expression: %s" (nth 1 old)))
174 (or (math-expr-contains expr old)
175 (error "No occurrences found")))
176 (calc-enter-result num "sbst" (math-expr-subst expr old new)))))
177
178
179 (defun calc-has-rules (name)
180 (setq name (calc-var-value name))
181 (and (consp name)
182 (memq (car name) '(vec calcFunc-assign calcFunc-condition))
183 name))
184
185 ;; math-eval-rules-cache and math-eval-rules-cache-other are
186 ;; declared in calc.el, but are used here by math-recompile-eval-rules.
187 (defvar math-eval-rules-cache)
188 (defvar math-eval-rules-cache-other)
189
190 (defun math-recompile-eval-rules ()
191 (setq math-eval-rules-cache (and (calc-has-rules 'var-EvalRules)
192 (math-compile-rewrites
193 '(var EvalRules var-EvalRules)))
194 math-eval-rules-cache-other (assq nil math-eval-rules-cache)
195 math-eval-rules-cache-tag (calc-var-value 'var-EvalRules)))
196
197
198 ;;; Try to expand a formula according to its definition.
199 (defun math-expand-formula (expr)
200 (and (consp expr)
201 (symbolp (car expr))
202 (or (get (car expr) 'calc-user-defn)
203 (get (car expr) 'math-expandable))
204 (let ((res (let ((math-expand-formulas t))
205 (apply (car expr) (cdr expr)))))
206 (and (not (eq (car-safe res) (car expr)))
207 res))))
208
209
210
211
212 ;;; True if A comes before B in a canonical ordering of expressions. [P X X]
213 (defun math-beforep (a b) ; [Public]
214 (cond ((and (Math-realp a) (Math-realp b))
215 (let ((comp (math-compare a b)))
216 (or (eq comp -1)
217 (and (eq comp 0)
218 (not (equal a b))
219 (> (length (memq (car-safe a)
220 '(bigneg nil bigpos frac float)))
221 (length (memq (car-safe b)
222 '(bigneg nil bigpos frac float))))))))
223 ((equal b '(neg (var inf var-inf))) nil)
224 ((equal a '(neg (var inf var-inf))) t)
225 ((equal a '(var inf var-inf)) nil)
226 ((equal b '(var inf var-inf)) t)
227 ((Math-realp a)
228 (if (and (eq (car-safe b) 'intv) (math-intv-constp b))
229 (if (or (math-beforep a (nth 2 b)) (Math-equal a (nth 2 b)))
230 t
231 nil)
232 t))
233 ((Math-realp b)
234 (if (and (eq (car-safe a) 'intv) (math-intv-constp a))
235 (if (math-beforep (nth 2 a) b)
236 t
237 nil)
238 nil))
239 ((and (eq (car a) 'intv) (eq (car b) 'intv)
240 (math-intv-constp a) (math-intv-constp b))
241 (let ((comp (math-compare (nth 2 a) (nth 2 b))))
242 (cond ((eq comp -1) t)
243 ((eq comp 1) nil)
244 ((and (memq (nth 1 a) '(2 3)) (memq (nth 1 b) '(0 1))) t)
245 ((and (memq (nth 1 a) '(0 1)) (memq (nth 1 b) '(2 3))) nil)
246 ((eq (setq comp (math-compare (nth 3 a) (nth 3 b))) -1) t)
247 ((eq comp 1) nil)
248 ((and (memq (nth 1 a) '(0 2)) (memq (nth 1 b) '(1 3))) t)
249 (t nil))))
250 ((not (eq (not (Math-objectp a)) (not (Math-objectp b))))
251 (Math-objectp a))
252 ((eq (car a) 'var)
253 (if (eq (car b) 'var)
254 (string-lessp (symbol-name (nth 1 a)) (symbol-name (nth 1 b)))
255 (not (Math-numberp b))))
256 ((eq (car b) 'var) (Math-numberp a))
257 ((eq (car a) (car b))
258 (while (and (setq a (cdr a) b (cdr b)) a
259 (equal (car a) (car b))))
260 (and b
261 (or (null a)
262 (math-beforep (car a) (car b)))))
263 (t (string-lessp (symbol-name (car a)) (symbol-name (car b))))))
264
265
266 (defsubst math-simplify-extended (a)
267 (let ((math-living-dangerously t))
268 (math-simplify a)))
269
270 (defalias 'calcFunc-esimplify 'math-simplify-extended)
271
272 ;; math-top-only is local to math-simplify, but is used by
273 ;; math-simplify-step, which is called by math-simplify.
274 (defvar math-top-only)
275
276 (defun math-simplify (top-expr)
277 (let ((math-simplifying t)
278 (math-top-only (consp calc-simplify-mode))
279 (simp-rules (append (and (calc-has-rules 'var-AlgSimpRules)
280 '((var AlgSimpRules var-AlgSimpRules)))
281 (and math-living-dangerously
282 (calc-has-rules 'var-ExtSimpRules)
283 '((var ExtSimpRules var-ExtSimpRules)))
284 (and math-simplifying-units
285 (calc-has-rules 'var-UnitSimpRules)
286 '((var UnitSimpRules var-UnitSimpRules)))
287 (and math-integrating
288 (calc-has-rules 'var-IntegSimpRules)
289 '((var IntegSimpRules var-IntegSimpRules)))))
290 res)
291 (if math-top-only
292 (let ((r simp-rules))
293 (setq res (math-simplify-step (math-normalize top-expr))
294 calc-simplify-mode '(nil)
295 top-expr (math-normalize res))
296 (while r
297 (setq top-expr (math-rewrite top-expr (car r)
298 '(neg (var inf var-inf)))
299 r (cdr r))))
300 (calc-with-default-simplification
301 (while (let ((r simp-rules))
302 (setq res (math-normalize top-expr))
303 (while r
304 (setq res (math-rewrite res (car r))
305 r (cdr r)))
306 (not (equal top-expr (setq res (math-simplify-step res)))))
307 (setq top-expr res)))))
308 top-expr)
309
310 (defalias 'calcFunc-simplify 'math-simplify)
311
312 ;;; The following has a "bug" in that if any recursive simplifications
313 ;;; occur only the first handler will be tried; this doesn't really
314 ;;; matter, since math-simplify-step is iterated to a fixed point anyway.
315 (defun math-simplify-step (a)
316 (if (Math-primp a)
317 a
318 (let ((aa (if (or math-top-only
319 (memq (car a) '(calcFunc-quote calcFunc-condition
320 calcFunc-evalto)))
321 a
322 (cons (car a) (mapcar 'math-simplify-step (cdr a))))))
323 (and (symbolp (car aa))
324 (let ((handler (get (car aa) 'math-simplify)))
325 (and handler
326 (while (and handler
327 (equal (setq aa (or (funcall (car handler) aa)
328 aa))
329 a))
330 (setq handler (cdr handler))))))
331 aa)))
332
333
334 (defmacro math-defsimplify (funcs &rest code)
335 (append '(progn)
336 (mapcar (function
337 (lambda (func)
338 (list 'put (list 'quote func) ''math-simplify
339 (list 'nconc
340 (list 'get (list 'quote func) ''math-simplify)
341 (list 'list
342 (list 'function
343 (append '(lambda (math-simplify-expr))
344 code)))))))
345 (if (symbolp funcs) (list funcs) funcs))))
346 (put 'math-defsimplify 'lisp-indent-hook 1)
347
348 ;; The function created by math-defsimplify uses the variable
349 ;; math-simplify-expr, and so is used by functions in math-defsimplify
350 (defvar math-simplify-expr)
351
352 (math-defsimplify (+ -)
353 (math-simplify-plus))
354
355 (defun math-simplify-plus ()
356 (cond ((and (memq (car-safe (nth 1 math-simplify-expr)) '(+ -))
357 (Math-numberp (nth 2 (nth 1 math-simplify-expr)))
358 (not (Math-numberp (nth 2 math-simplify-expr))))
359 (let ((x (nth 2 math-simplify-expr))
360 (op (car math-simplify-expr)))
361 (setcar (cdr (cdr math-simplify-expr)) (nth 2 (nth 1 math-simplify-expr)))
362 (setcar math-simplify-expr (car (nth 1 math-simplify-expr)))
363 (setcar (cdr (cdr (nth 1 math-simplify-expr))) x)
364 (setcar (nth 1 math-simplify-expr) op)))
365 ((and (eq (car math-simplify-expr) '+)
366 (Math-numberp (nth 1 math-simplify-expr))
367 (not (Math-numberp (nth 2 math-simplify-expr))))
368 (let ((x (nth 2 math-simplify-expr)))
369 (setcar (cdr (cdr math-simplify-expr)) (nth 1 math-simplify-expr))
370 (setcar (cdr math-simplify-expr) x))))
371 (let ((aa math-simplify-expr)
372 aaa temp)
373 (while (memq (car-safe (setq aaa (nth 1 aa))) '(+ -))
374 (if (setq temp (math-combine-sum (nth 2 aaa) (nth 2 math-simplify-expr)
375 (eq (car aaa) '-)
376 (eq (car math-simplify-expr) '-) t))
377 (progn
378 (setcar (cdr (cdr math-simplify-expr)) temp)
379 (setcar math-simplify-expr '+)
380 (setcar (cdr (cdr aaa)) 0)))
381 (setq aa (nth 1 aa)))
382 (if (setq temp (math-combine-sum aaa (nth 2 math-simplify-expr)
383 nil (eq (car math-simplify-expr) '-) t))
384 (progn
385 (setcar (cdr (cdr math-simplify-expr)) temp)
386 (setcar math-simplify-expr '+)
387 (setcar (cdr aa) 0)))
388 math-simplify-expr))
389
390 (math-defsimplify *
391 (math-simplify-times))
392
393 (defun math-simplify-times ()
394 (if (eq (car-safe (nth 2 math-simplify-expr)) '*)
395 (and (math-beforep (nth 1 (nth 2 math-simplify-expr)) (nth 1 math-simplify-expr))
396 (or (math-known-scalarp (nth 1 math-simplify-expr) t)
397 (math-known-scalarp (nth 1 (nth 2 math-simplify-expr)) t))
398 (let ((x (nth 1 math-simplify-expr)))
399 (setcar (cdr math-simplify-expr) (nth 1 (nth 2 math-simplify-expr)))
400 (setcar (cdr (nth 2 math-simplify-expr)) x)))
401 (and (math-beforep (nth 2 math-simplify-expr) (nth 1 math-simplify-expr))
402 (or (math-known-scalarp (nth 1 math-simplify-expr) t)
403 (math-known-scalarp (nth 2 math-simplify-expr) t))
404 (let ((x (nth 2 math-simplify-expr)))
405 (setcar (cdr (cdr math-simplify-expr)) (nth 1 math-simplify-expr))
406 (setcar (cdr math-simplify-expr) x))))
407 (let ((aa math-simplify-expr)
408 aaa temp
409 (safe t) (scalar (math-known-scalarp (nth 1 math-simplify-expr))))
410 (if (and (Math-ratp (nth 1 math-simplify-expr))
411 (setq temp (math-common-constant-factor (nth 2 math-simplify-expr))))
412 (progn
413 (setcar (cdr (cdr math-simplify-expr))
414 (math-cancel-common-factor (nth 2 math-simplify-expr) temp))
415 (setcar (cdr math-simplify-expr) (math-mul (nth 1 math-simplify-expr) temp))))
416 (while (and (eq (car-safe (setq aaa (nth 2 aa))) '*)
417 safe)
418 (if (setq temp (math-combine-prod (nth 1 math-simplify-expr)
419 (nth 1 aaa) nil nil t))
420 (progn
421 (setcar (cdr math-simplify-expr) temp)
422 (setcar (cdr aaa) 1)))
423 (setq safe (or scalar (math-known-scalarp (nth 1 aaa) t))
424 aa (nth 2 aa)))
425 (if (and (setq temp (math-combine-prod aaa (nth 1 math-simplify-expr) nil nil t))
426 safe)
427 (progn
428 (setcar (cdr math-simplify-expr) temp)
429 (setcar (cdr (cdr aa)) 1)))
430 (if (and (eq (car-safe (nth 1 math-simplify-expr)) 'frac)
431 (memq (nth 1 (nth 1 math-simplify-expr)) '(1 -1)))
432 (math-div (math-mul (nth 2 math-simplify-expr)
433 (nth 1 (nth 1 math-simplify-expr)))
434 (nth 2 (nth 1 math-simplify-expr)))
435 math-simplify-expr)))
436
437 (math-defsimplify /
438 (math-simplify-divide))
439
440 (defun math-simplify-divide ()
441 (let ((np (cdr math-simplify-expr))
442 (nover nil)
443 (nn (and (or (eq (car math-simplify-expr) '/)
444 (not (Math-realp (nth 2 math-simplify-expr))))
445 (math-common-constant-factor (nth 2 math-simplify-expr))))
446 n op)
447 (if nn
448 (progn
449 (setq n (and (or (eq (car math-simplify-expr) '/)
450 (not (Math-realp (nth 1 math-simplify-expr))))
451 (math-common-constant-factor (nth 1 math-simplify-expr))))
452 (if (and (eq (car-safe nn) 'frac) (eq (nth 1 nn) 1) (not n))
453 (progn
454 (setcar (cdr math-simplify-expr)
455 (math-mul (nth 2 nn) (nth 1 math-simplify-expr)))
456 (setcar (cdr (cdr math-simplify-expr))
457 (math-cancel-common-factor (nth 2 math-simplify-expr) nn))
458 (if (and (math-negp nn)
459 (setq op (assq (car math-simplify-expr) calc-tweak-eqn-table)))
460 (setcar math-simplify-expr (nth 1 op))))
461 (if (and n (not (eq (setq n (math-frac-gcd n nn)) 1)))
462 (progn
463 (setcar (cdr math-simplify-expr)
464 (math-cancel-common-factor (nth 1 math-simplify-expr) n))
465 (setcar (cdr (cdr math-simplify-expr))
466 (math-cancel-common-factor (nth 2 math-simplify-expr) n))
467 (if (and (math-negp n)
468 (setq op (assq (car math-simplify-expr)
469 calc-tweak-eqn-table)))
470 (setcar math-simplify-expr (nth 1 op))))))))
471 (if (and (eq (car-safe (car np)) '/)
472 (math-known-scalarp (nth 2 math-simplify-expr) t))
473 (progn
474 (setq np (cdr (nth 1 math-simplify-expr)))
475 (while (eq (car-safe (setq n (car np))) '*)
476 (and (math-known-scalarp (nth 2 n) t)
477 (math-simplify-divisor (cdr n) (cdr (cdr math-simplify-expr)) nil t))
478 (setq np (cdr (cdr n))))
479 (math-simplify-divisor np (cdr (cdr math-simplify-expr)) nil t)
480 (setq nover t
481 np (cdr (cdr (nth 1 math-simplify-expr))))))
482 (while (eq (car-safe (setq n (car np))) '*)
483 (and (math-known-scalarp (nth 2 n) t)
484 (math-simplify-divisor (cdr n) (cdr (cdr math-simplify-expr)) nover t))
485 (setq np (cdr (cdr n))))
486 (math-simplify-divisor np (cdr (cdr math-simplify-expr)) nover t)
487 math-simplify-expr))
488
489 ;; The variables math-simplify-divisor-nover and math-simplify-divisor-dover
490 ;; are local variables for math-simplify-divisor, but are used by
491 ;; math-simplify-one-divisor.
492 (defvar math-simplify-divisor-nover)
493 (defvar math-simplify-divisor-dover)
494
495 (defun math-simplify-divisor (np dp math-simplify-divisor-nover
496 math-simplify-divisor-dover)
497 (cond ((eq (car-safe (car dp)) '/)
498 (math-simplify-divisor np (cdr (car dp))
499 math-simplify-divisor-nover
500 math-simplify-divisor-dover)
501 (and (math-known-scalarp (nth 1 (car dp)) t)
502 (math-simplify-divisor np (cdr (cdr (car dp)))
503 math-simplify-divisor-nover
504 (not math-simplify-divisor-dover))))
505 ((or (or (eq (car math-simplify-expr) '/)
506 (let ((signs (math-possible-signs (car np))))
507 (or (memq signs '(1 4))
508 (and (memq (car math-simplify-expr) '(calcFunc-eq calcFunc-neq))
509 (eq signs 5))
510 math-living-dangerously)))
511 (math-numberp (car np)))
512 (let (d
513 (safe t)
514 (scalar (math-known-scalarp (car np))))
515 (while (and (eq (car-safe (setq d (car dp))) '*)
516 safe)
517 (math-simplify-one-divisor np (cdr d))
518 (setq safe (or scalar (math-known-scalarp (nth 1 d) t))
519 dp (cdr (cdr d))))
520 (if safe
521 (math-simplify-one-divisor np dp))))))
522
523 (defun math-simplify-one-divisor (np dp)
524 (let ((temp (math-combine-prod (car np) (car dp) math-simplify-divisor-nover
525 math-simplify-divisor-dover t))
526 op)
527 (if temp
528 (progn
529 (and (not (memq (car math-simplify-expr) '(/ calcFunc-eq calcFunc-neq)))
530 (math-known-negp (car dp))
531 (setq op (assq (car math-simplify-expr) calc-tweak-eqn-table))
532 (setcar math-simplify-expr (nth 1 op)))
533 (setcar np (if math-simplify-divisor-nover (math-div 1 temp) temp))
534 (setcar dp 1))
535 (and math-simplify-divisor-dover (not math-simplify-divisor-nover)
536 (eq (car math-simplify-expr) '/)
537 (eq (car-safe (car dp)) 'calcFunc-sqrt)
538 (Math-integerp (nth 1 (car dp)))
539 (progn
540 (setcar np (math-mul (car np)
541 (list 'calcFunc-sqrt (nth 1 (car dp)))))
542 (setcar dp (nth 1 (car dp))))))))
543
544 (defun math-common-constant-factor (expr)
545 (if (Math-realp expr)
546 (if (Math-ratp expr)
547 (and (not (memq expr '(0 1 -1)))
548 (math-abs expr))
549 (if (math-ratp (setq expr (math-to-simple-fraction expr)))
550 (math-common-constant-factor expr)))
551 (if (memq (car expr) '(+ - cplx sdev))
552 (let ((f1 (math-common-constant-factor (nth 1 expr)))
553 (f2 (math-common-constant-factor (nth 2 expr))))
554 (and f1 f2
555 (not (eq (setq f1 (math-frac-gcd f1 f2)) 1))
556 f1))
557 (if (memq (car expr) '(* polar))
558 (math-common-constant-factor (nth 1 expr))
559 (if (eq (car expr) '/)
560 (or (math-common-constant-factor (nth 1 expr))
561 (and (Math-integerp (nth 2 expr))
562 (list 'frac 1 (math-abs (nth 2 expr))))))))))
563
564 (defun math-cancel-common-factor (expr val)
565 (if (memq (car-safe expr) '(+ - cplx sdev))
566 (progn
567 (setcar (cdr expr) (math-cancel-common-factor (nth 1 expr) val))
568 (setcar (cdr (cdr expr)) (math-cancel-common-factor (nth 2 expr) val))
569 expr)
570 (if (eq (car-safe expr) '*)
571 (math-mul (math-cancel-common-factor (nth 1 expr) val) (nth 2 expr))
572 (math-div expr val))))
573
574 (defun math-frac-gcd (a b)
575 (if (Math-zerop a)
576 b
577 (if (Math-zerop b)
578 a
579 (if (and (Math-integerp a)
580 (Math-integerp b))
581 (math-gcd a b)
582 (and (Math-integerp a) (setq a (list 'frac a 1)))
583 (and (Math-integerp b) (setq b (list 'frac b 1)))
584 (math-make-frac (math-gcd (nth 1 a) (nth 1 b))
585 (math-gcd (nth 2 a) (nth 2 b)))))))
586
587 (math-defsimplify %
588 (math-simplify-mod))
589
590 (defun math-simplify-mod ()
591 (and (Math-realp (nth 2 math-simplify-expr))
592 (Math-posp (nth 2 math-simplify-expr))
593 (let ((lin (math-is-linear (nth 1 math-simplify-expr)))
594 t1 t2 t3)
595 (or (and lin
596 (or (math-negp (car lin))
597 (not (Math-lessp (car lin) (nth 2 math-simplify-expr))))
598 (list '%
599 (list '+
600 (math-mul (nth 1 lin) (nth 2 lin))
601 (math-mod (car lin) (nth 2 math-simplify-expr)))
602 (nth 2 math-simplify-expr)))
603 (and lin
604 (not (math-equal-int (nth 1 lin) 1))
605 (math-num-integerp (nth 1 lin))
606 (math-num-integerp (nth 2 math-simplify-expr))
607 (setq t1 (calcFunc-gcd (nth 1 lin) (nth 2 math-simplify-expr)))
608 (not (math-equal-int t1 1))
609 (list '*
610 t1
611 (list '%
612 (list '+
613 (math-mul (math-div (nth 1 lin) t1)
614 (nth 2 lin))
615 (let ((calc-prefer-frac t))
616 (math-div (car lin) t1)))
617 (math-div (nth 2 math-simplify-expr) t1))))
618 (and (math-equal-int (nth 2 math-simplify-expr) 1)
619 (math-known-integerp (if lin
620 (math-mul (nth 1 lin) (nth 2 lin))
621 (nth 1 math-simplify-expr)))
622 (if lin (math-mod (car lin) 1) 0))))))
623
624 (math-defsimplify (calcFunc-eq calcFunc-neq calcFunc-lt
625 calcFunc-gt calcFunc-leq calcFunc-geq)
626 (if (= (length math-simplify-expr) 3)
627 (math-simplify-ineq)))
628
629 (defun math-simplify-ineq ()
630 (let ((np (cdr math-simplify-expr))
631 n)
632 (while (memq (car-safe (setq n (car np))) '(+ -))
633 (math-simplify-add-term (cdr (cdr n)) (cdr (cdr math-simplify-expr))
634 (eq (car n) '-) nil)
635 (setq np (cdr n)))
636 (math-simplify-add-term np (cdr (cdr math-simplify-expr)) nil
637 (eq np (cdr math-simplify-expr)))
638 (math-simplify-divide)
639 (let ((signs (math-possible-signs (cons '- (cdr math-simplify-expr)))))
640 (or (cond ((eq (car math-simplify-expr) 'calcFunc-eq)
641 (or (and (eq signs 2) 1)
642 (and (memq signs '(1 4 5)) 0)))
643 ((eq (car math-simplify-expr) 'calcFunc-neq)
644 (or (and (eq signs 2) 0)
645 (and (memq signs '(1 4 5)) 1)))
646 ((eq (car math-simplify-expr) 'calcFunc-lt)
647 (or (and (eq signs 1) 1)
648 (and (memq signs '(2 4 6)) 0)))
649 ((eq (car math-simplify-expr) 'calcFunc-gt)
650 (or (and (eq signs 4) 1)
651 (and (memq signs '(1 2 3)) 0)))
652 ((eq (car math-simplify-expr) 'calcFunc-leq)
653 (or (and (eq signs 4) 0)
654 (and (memq signs '(1 2 3)) 1)))
655 ((eq (car math-simplify-expr) 'calcFunc-geq)
656 (or (and (eq signs 1) 0)
657 (and (memq signs '(2 4 6)) 1))))
658 math-simplify-expr))))
659
660 (defun math-simplify-add-term (np dp minus lplain)
661 (or (math-vectorp (car np))
662 (let ((rplain t)
663 n d dd temp)
664 (while (memq (car-safe (setq n (car np) d (car dp))) '(+ -))
665 (setq rplain nil)
666 (if (setq temp (math-combine-sum n (nth 2 d)
667 minus (eq (car d) '+) t))
668 (if (or lplain (eq (math-looks-negp temp) minus))
669 (progn
670 (setcar np (setq n (if minus (math-neg temp) temp)))
671 (setcar (cdr (cdr d)) 0))
672 (progn
673 (setcar np 0)
674 (setcar (cdr (cdr d)) (setq n (if (eq (car d) '+)
675 (math-neg temp)
676 temp))))))
677 (setq dp (cdr d)))
678 (if (setq temp (math-combine-sum n d minus t t))
679 (if (or lplain
680 (and (not rplain)
681 (eq (math-looks-negp temp) minus)))
682 (progn
683 (setcar np (setq n (if minus (math-neg temp) temp)))
684 (setcar dp 0))
685 (progn
686 (setcar np 0)
687 (setcar dp (setq n (math-neg temp)))))))))
688
689 (math-defsimplify calcFunc-sin
690 (or (and (eq (car-safe (nth 1 math-simplify-expr)) 'calcFunc-arcsin)
691 (nth 1 (nth 1 math-simplify-expr)))
692 (and (math-looks-negp (nth 1 math-simplify-expr))
693 (math-neg (list 'calcFunc-sin (math-neg (nth 1 math-simplify-expr)))))
694 (and (eq calc-angle-mode 'rad)
695 (let ((n (math-linear-in (nth 1 math-simplify-expr) '(var pi var-pi))))
696 (and n
697 (math-known-sin (car n) (nth 1 n) 120 0))))
698 (and (eq calc-angle-mode 'deg)
699 (let ((n (math-integer-plus (nth 1 math-simplify-expr))))
700 (and n
701 (math-known-sin (car n) (nth 1 n) '(frac 2 3) 0))))
702 (and (eq (car-safe (nth 1 math-simplify-expr)) 'calcFunc-arccos)
703 (list 'calcFunc-sqrt (math-sub 1 (math-sqr
704 (nth 1 (nth 1 math-simplify-expr))))))
705 (and (eq (car-safe (nth 1 math-simplify-expr)) 'calcFunc-arctan)
706 (math-div (nth 1 (nth 1 math-simplify-expr))
707 (list 'calcFunc-sqrt
708 (math-add 1 (math-sqr
709 (nth 1 (nth 1 math-simplify-expr)))))))
710 (let ((m (math-should-expand-trig (nth 1 math-simplify-expr))))
711 (and m (integerp (car m))
712 (let ((n (car m)) (a (nth 1 m)))
713 (list '+
714 (list '* (list 'calcFunc-sin (list '* (1- n) a))
715 (list 'calcFunc-cos a))
716 (list '* (list 'calcFunc-cos (list '* (1- n) a))
717 (list 'calcFunc-sin a))))))))
718
719 (math-defsimplify calcFunc-cos
720 (or (and (eq (car-safe (nth 1 math-simplify-expr)) 'calcFunc-arccos)
721 (nth 1 (nth 1 math-simplify-expr)))
722 (and (math-looks-negp (nth 1 math-simplify-expr))
723 (list 'calcFunc-cos (math-neg (nth 1 math-simplify-expr))))
724 (and (eq calc-angle-mode 'rad)
725 (let ((n (math-linear-in (nth 1 math-simplify-expr) '(var pi var-pi))))
726 (and n
727 (math-known-sin (car n) (nth 1 n) 120 300))))
728 (and (eq calc-angle-mode 'deg)
729 (let ((n (math-integer-plus (nth 1 math-simplify-expr))))
730 (and n
731 (math-known-sin (car n) (nth 1 n) '(frac 2 3) 300))))
732 (and (eq (car-safe (nth 1 math-simplify-expr)) 'calcFunc-arcsin)
733 (list 'calcFunc-sqrt
734 (math-sub 1 (math-sqr (nth 1 (nth 1 math-simplify-expr))))))
735 (and (eq (car-safe (nth 1 math-simplify-expr)) 'calcFunc-arctan)
736 (math-div 1
737 (list 'calcFunc-sqrt
738 (math-add 1
739 (math-sqr (nth 1 (nth 1 math-simplify-expr)))))))
740 (let ((m (math-should-expand-trig (nth 1 math-simplify-expr))))
741 (and m (integerp (car m))
742 (let ((n (car m)) (a (nth 1 m)))
743 (list '-
744 (list '* (list 'calcFunc-cos (list '* (1- n) a))
745 (list 'calcFunc-cos a))
746 (list '* (list 'calcFunc-sin (list '* (1- n) a))
747 (list 'calcFunc-sin a))))))))
748
749 (math-defsimplify calcFunc-sec
750 (or (and (math-looks-negp (nth 1 math-simplify-expr))
751 (list 'calcFunc-sec (math-neg (nth 1 math-simplify-expr))))
752 (and (eq calc-angle-mode 'rad)
753 (let ((n (math-linear-in (nth 1 math-simplify-expr) '(var pi var-pi))))
754 (and n
755 (math-div 1 (math-known-sin (car n) (nth 1 n) 120 300)))))
756 (and (eq calc-angle-mode 'deg)
757 (let ((n (math-integer-plus (nth 1 math-simplify-expr))))
758 (and n
759 (math-div 1 (math-known-sin (car n) (nth 1 n) '(frac 2 3) 300)))))
760 (and (eq (car-safe (nth 1 math-simplify-expr)) 'calcFunc-arcsin)
761 (math-div
762 1
763 (list 'calcFunc-sqrt
764 (math-sub 1 (math-sqr (nth 1 (nth 1 math-simplify-expr)))))))
765 (and (eq (car-safe (nth 1 math-simplify-expr)) 'calcFunc-arccos)
766 (math-div
767 1
768 (nth 1 (nth 1 math-simplify-expr))))
769 (and (eq (car-safe (nth 1 math-simplify-expr)) 'calcFunc-arctan)
770 (list 'calcFunc-sqrt
771 (math-add 1
772 (math-sqr (nth 1 (nth 1 math-simplify-expr))))))))
773
774 (math-defsimplify calcFunc-csc
775 (or (and (math-looks-negp (nth 1 math-simplify-expr))
776 (math-neg (list 'calcFunc-csc (math-neg (nth 1 math-simplify-expr)))))
777 (and (eq calc-angle-mode 'rad)
778 (let ((n (math-linear-in (nth 1 math-simplify-expr) '(var pi var-pi))))
779 (and n
780 (math-div 1 (math-known-sin (car n) (nth 1 n) 120 0)))))
781 (and (eq calc-angle-mode 'deg)
782 (let ((n (math-integer-plus (nth 1 math-simplify-expr))))
783 (and n
784 (math-div 1 (math-known-sin (car n) (nth 1 n) '(frac 2 3) 0)))))
785 (and (eq (car-safe (nth 1 math-simplify-expr)) 'calcFunc-arcsin)
786 (math-div 1 (nth 1 (nth 1 math-simplify-expr))))
787 (and (eq (car-safe (nth 1 math-simplify-expr)) 'calcFunc-arccos)
788 (math-div
789 1
790 (list 'calcFunc-sqrt (math-sub 1 (math-sqr
791 (nth 1 (nth 1 math-simplify-expr)))))))
792 (and (eq (car-safe (nth 1 math-simplify-expr)) 'calcFunc-arctan)
793 (math-div (list 'calcFunc-sqrt
794 (math-add 1 (math-sqr
795 (nth 1 (nth 1 math-simplify-expr)))))
796 (nth 1 (nth 1 math-simplify-expr))))))
797
798 (defun math-should-expand-trig (x &optional hyperbolic)
799 (let ((m (math-is-multiple x)))
800 (and math-living-dangerously
801 m (or (and (integerp (car m)) (> (car m) 1))
802 (equal (car m) '(frac 1 2)))
803 (or math-integrating
804 (memq (car-safe (nth 1 m))
805 (if hyperbolic
806 '(calcFunc-arcsinh calcFunc-arccosh calcFunc-arctanh)
807 '(calcFunc-arcsin calcFunc-arccos calcFunc-arctan)))
808 (and (eq (car-safe (nth 1 m)) 'calcFunc-ln)
809 (eq hyperbolic 'exp)))
810 m)))
811
812 (defun math-known-sin (plus n mul off)
813 (setq n (math-mul n mul))
814 (and (math-num-integerp n)
815 (setq n (math-mod (math-add (math-trunc n) off) 240))
816 (if (>= n 120)
817 (and (setq n (math-known-sin plus (- n 120) 1 0))
818 (math-neg n))
819 (if (> n 60)
820 (setq n (- 120 n)))
821 (if (math-zerop plus)
822 (and (or calc-symbolic-mode
823 (memq n '(0 20 60)))
824 (cdr (assq n
825 '( (0 . 0)
826 (10 . (/ (calcFunc-sqrt
827 (- 2 (calcFunc-sqrt 3))) 2))
828 (12 . (/ (- (calcFunc-sqrt 5) 1) 4))
829 (15 . (/ (calcFunc-sqrt
830 (- 2 (calcFunc-sqrt 2))) 2))
831 (20 . (/ 1 2))
832 (24 . (* (^ (/ 1 2) (/ 3 2))
833 (calcFunc-sqrt
834 (- 5 (calcFunc-sqrt 5)))))
835 (30 . (/ (calcFunc-sqrt 2) 2))
836 (36 . (/ (+ (calcFunc-sqrt 5) 1) 4))
837 (40 . (/ (calcFunc-sqrt 3) 2))
838 (45 . (/ (calcFunc-sqrt
839 (+ 2 (calcFunc-sqrt 2))) 2))
840 (48 . (* (^ (/ 1 2) (/ 3 2))
841 (calcFunc-sqrt
842 (+ 5 (calcFunc-sqrt 5)))))
843 (50 . (/ (calcFunc-sqrt
844 (+ 2 (calcFunc-sqrt 3))) 2))
845 (60 . 1)))))
846 (cond ((eq n 0) (math-normalize (list 'calcFunc-sin plus)))
847 ((eq n 60) (math-normalize (list 'calcFunc-cos plus)))
848 (t nil))))))
849
850 (math-defsimplify calcFunc-tan
851 (or (and (eq (car-safe (nth 1 math-simplify-expr)) 'calcFunc-arctan)
852 (nth 1 (nth 1 math-simplify-expr)))
853 (and (math-looks-negp (nth 1 math-simplify-expr))
854 (math-neg (list 'calcFunc-tan (math-neg (nth 1 math-simplify-expr)))))
855 (and (eq calc-angle-mode 'rad)
856 (let ((n (math-linear-in (nth 1 math-simplify-expr) '(var pi var-pi))))
857 (and n
858 (math-known-tan (car n) (nth 1 n) 120))))
859 (and (eq calc-angle-mode 'deg)
860 (let ((n (math-integer-plus (nth 1 math-simplify-expr))))
861 (and n
862 (math-known-tan (car n) (nth 1 n) '(frac 2 3)))))
863 (and (eq (car-safe (nth 1 math-simplify-expr)) 'calcFunc-arcsin)
864 (math-div (nth 1 (nth 1 math-simplify-expr))
865 (list 'calcFunc-sqrt
866 (math-sub 1 (math-sqr (nth 1 (nth 1 math-simplify-expr)))))))
867 (and (eq (car-safe (nth 1 math-simplify-expr)) 'calcFunc-arccos)
868 (math-div (list 'calcFunc-sqrt
869 (math-sub 1 (math-sqr (nth 1 (nth 1 math-simplify-expr)))))
870 (nth 1 (nth 1 math-simplify-expr))))
871 (let ((m (math-should-expand-trig (nth 1 math-simplify-expr))))
872 (and m
873 (if (equal (car m) '(frac 1 2))
874 (math-div (math-sub 1 (list 'calcFunc-cos (nth 1 m)))
875 (list 'calcFunc-sin (nth 1 m)))
876 (math-div (list 'calcFunc-sin (nth 1 math-simplify-expr))
877 (list 'calcFunc-cos (nth 1 math-simplify-expr))))))))
878
879 (math-defsimplify calcFunc-cot
880 (or (and (math-looks-negp (nth 1 math-simplify-expr))
881 (math-neg (list 'calcFunc-cot (math-neg (nth 1 math-simplify-expr)))))
882 (and (eq calc-angle-mode 'rad)
883 (let ((n (math-linear-in (nth 1 math-simplify-expr) '(var pi var-pi))))
884 (and n
885 (math-div 1 (math-known-tan (car n) (nth 1 n) 120)))))
886 (and (eq calc-angle-mode 'deg)
887 (let ((n (math-integer-plus (nth 1 math-simplify-expr))))
888 (and n
889 (math-div 1 (math-known-tan (car n) (nth 1 n) '(frac 2 3))))))
890 (and (eq (car-safe (nth 1 math-simplify-expr)) 'calcFunc-arcsin)
891 (math-div (list 'calcFunc-sqrt
892 (math-sub 1 (math-sqr (nth 1 (nth 1 math-simplify-expr)))))
893 (nth 1 (nth 1 math-simplify-expr))))
894 (and (eq (car-safe (nth 1 math-simplify-expr)) 'calcFunc-arccos)
895 (math-div (nth 1 (nth 1 math-simplify-expr))
896 (list 'calcFunc-sqrt
897 (math-sub 1 (math-sqr (nth 1 (nth 1 math-simplify-expr)))))))
898 (and (eq (car-safe (nth 1 math-simplify-expr)) 'calcFunc-arctan)
899 (math-div 1 (nth 1 (nth 1 math-simplify-expr))))))
900
901 (defun math-known-tan (plus n mul)
902 (setq n (math-mul n mul))
903 (and (math-num-integerp n)
904 (setq n (math-mod (math-trunc n) 120))
905 (if (> n 60)
906 (and (setq n (math-known-tan plus (- 120 n) 1))
907 (math-neg n))
908 (if (math-zerop plus)
909 (and (or calc-symbolic-mode
910 (memq n '(0 30 60)))
911 (cdr (assq n '( (0 . 0)
912 (10 . (- 2 (calcFunc-sqrt 3)))
913 (12 . (calcFunc-sqrt
914 (- 1 (* (/ 2 5) (calcFunc-sqrt 5)))))
915 (15 . (- (calcFunc-sqrt 2) 1))
916 (20 . (/ (calcFunc-sqrt 3) 3))
917 (24 . (calcFunc-sqrt
918 (- 5 (* 2 (calcFunc-sqrt 5)))))
919 (30 . 1)
920 (36 . (calcFunc-sqrt
921 (+ 1 (* (/ 2 5) (calcFunc-sqrt 5)))))
922 (40 . (calcFunc-sqrt 3))
923 (45 . (+ (calcFunc-sqrt 2) 1))
924 (48 . (calcFunc-sqrt
925 (+ 5 (* 2 (calcFunc-sqrt 5)))))
926 (50 . (+ 2 (calcFunc-sqrt 3)))
927 (60 . (var uinf var-uinf))))))
928 (cond ((eq n 0) (math-normalize (list 'calcFunc-tan plus)))
929 ((eq n 60) (math-normalize (list '/ -1
930 (list 'calcFunc-tan plus))))
931 (t nil))))))
932
933 (math-defsimplify calcFunc-sinh
934 (or (and (eq (car-safe (nth 1 math-simplify-expr)) 'calcFunc-arcsinh)
935 (nth 1 (nth 1 math-simplify-expr)))
936 (and (math-looks-negp (nth 1 math-simplify-expr))
937 (math-neg (list 'calcFunc-sinh (math-neg (nth 1 math-simplify-expr)))))
938 (and (eq (car-safe (nth 1 math-simplify-expr)) 'calcFunc-arccosh)
939 math-living-dangerously
940 (list 'calcFunc-sqrt
941 (math-sub (math-sqr (nth 1 (nth 1 math-simplify-expr))) 1)))
942 (and (eq (car-safe (nth 1 math-simplify-expr)) 'calcFunc-arctanh)
943 math-living-dangerously
944 (math-div (nth 1 (nth 1 math-simplify-expr))
945 (list 'calcFunc-sqrt
946 (math-sub 1 (math-sqr (nth 1 (nth 1 math-simplify-expr)))))))
947 (let ((m (math-should-expand-trig (nth 1 math-simplify-expr) t)))
948 (and m (integerp (car m))
949 (let ((n (car m)) (a (nth 1 m)))
950 (if (> n 1)
951 (list '+
952 (list '* (list 'calcFunc-sinh (list '* (1- n) a))
953 (list 'calcFunc-cosh a))
954 (list '* (list 'calcFunc-cosh (list '* (1- n) a))
955 (list 'calcFunc-sinh a)))))))))
956
957 (math-defsimplify calcFunc-cosh
958 (or (and (eq (car-safe (nth 1 math-simplify-expr)) 'calcFunc-arccosh)
959 (nth 1 (nth 1 math-simplify-expr)))
960 (and (math-looks-negp (nth 1 math-simplify-expr))
961 (list 'calcFunc-cosh (math-neg (nth 1 math-simplify-expr))))
962 (and (eq (car-safe (nth 1 math-simplify-expr)) 'calcFunc-arcsinh)
963 math-living-dangerously
964 (list 'calcFunc-sqrt
965 (math-add (math-sqr (nth 1 (nth 1 math-simplify-expr))) 1)))
966 (and (eq (car-safe (nth 1 math-simplify-expr)) 'calcFunc-arctanh)
967 math-living-dangerously
968 (math-div 1
969 (list 'calcFunc-sqrt
970 (math-sub 1 (math-sqr (nth 1 (nth 1 math-simplify-expr)))))))
971 (let ((m (math-should-expand-trig (nth 1 math-simplify-expr) t)))
972 (and m (integerp (car m))
973 (let ((n (car m)) (a (nth 1 m)))
974 (if (> n 1)
975 (list '+
976 (list '* (list 'calcFunc-cosh (list '* (1- n) a))
977 (list 'calcFunc-cosh a))
978 (list '* (list 'calcFunc-sinh (list '* (1- n) a))
979 (list 'calcFunc-sinh a)))))))))
980
981 (math-defsimplify calcFunc-tanh
982 (or (and (eq (car-safe (nth 1 math-simplify-expr)) 'calcFunc-arctanh)
983 (nth 1 (nth 1 math-simplify-expr)))
984 (and (math-looks-negp (nth 1 math-simplify-expr))
985 (math-neg (list 'calcFunc-tanh (math-neg (nth 1 math-simplify-expr)))))
986 (and (eq (car-safe (nth 1 math-simplify-expr)) 'calcFunc-arcsinh)
987 math-living-dangerously
988 (math-div (nth 1 (nth 1 math-simplify-expr))
989 (list 'calcFunc-sqrt
990 (math-add (math-sqr (nth 1 (nth 1 math-simplify-expr))) 1))))
991 (and (eq (car-safe (nth 1 math-simplify-expr)) 'calcFunc-arccosh)
992 math-living-dangerously
993 (math-div (list 'calcFunc-sqrt
994 (math-sub (math-sqr (nth 1 (nth 1 math-simplify-expr))) 1))
995 (nth 1 (nth 1 math-simplify-expr))))
996 (let ((m (math-should-expand-trig (nth 1 math-simplify-expr) t)))
997 (and m
998 (if (equal (car m) '(frac 1 2))
999 (math-div (math-sub (list 'calcFunc-cosh (nth 1 m)) 1)
1000 (list 'calcFunc-sinh (nth 1 m)))
1001 (math-div (list 'calcFunc-sinh (nth 1 math-simplify-expr))
1002 (list 'calcFunc-cosh (nth 1 math-simplify-expr))))))))
1003
1004 (math-defsimplify calcFunc-sech
1005 (or (and (math-looks-negp (nth 1 math-simplify-expr))
1006 (list 'calcFunc-sech (math-neg (nth 1 math-simplify-expr))))
1007 (and (eq (car-safe (nth 1 math-simplify-expr)) 'calcFunc-arcsinh)
1008 math-living-dangerously
1009 (math-div
1010 1
1011 (list 'calcFunc-sqrt
1012 (math-add (math-sqr (nth 1 (nth 1 math-simplify-expr))) 1))))
1013 (and (eq (car-safe (nth 1 math-simplify-expr)) 'calcFunc-arccosh)
1014 math-living-dangerously
1015 (math-div 1 (nth 1 (nth 1 math-simplify-expr))) 1)
1016 (and (eq (car-safe (nth 1 math-simplify-expr)) 'calcFunc-arctanh)
1017 math-living-dangerously
1018 (list 'calcFunc-sqrt
1019 (math-sub 1 (math-sqr (nth 1 (nth 1 math-simplify-expr))))))))
1020
1021 (math-defsimplify calcFunc-csch
1022 (or (and (math-looks-negp (nth 1 math-simplify-expr))
1023 (math-neg (list 'calcFunc-csch (math-neg (nth 1 math-simplify-expr)))))
1024 (and (eq (car-safe (nth 1 math-simplify-expr)) 'calcFunc-arcsinh)
1025 math-living-dangerously
1026 (math-div 1 (nth 1 (nth 1 math-simplify-expr))))
1027 (and (eq (car-safe (nth 1 math-simplify-expr)) 'calcFunc-arccosh)
1028 math-living-dangerously
1029 (math-div
1030 1
1031 (list 'calcFunc-sqrt
1032 (math-sub (math-sqr (nth 1 (nth 1 math-simplify-expr))) 1))))
1033 (and (eq (car-safe (nth 1 math-simplify-expr)) 'calcFunc-arctanh)
1034 math-living-dangerously
1035 (math-div (list 'calcFunc-sqrt
1036 (math-sub 1 (math-sqr (nth 1 (nth 1 math-simplify-expr)))))
1037 (nth 1 (nth 1 math-simplify-expr))))))
1038
1039 (math-defsimplify calcFunc-coth
1040 (or (and (math-looks-negp (nth 1 math-simplify-expr))
1041 (math-neg (list 'calcFunc-coth (math-neg (nth 1 math-simplify-expr)))))
1042 (and (eq (car-safe (nth 1 math-simplify-expr)) 'calcFunc-arcsinh)
1043 math-living-dangerously
1044 (math-div (list 'calcFunc-sqrt
1045 (math-add (math-sqr (nth 1 (nth 1 math-simplify-expr))) 1))
1046 (nth 1 (nth 1 math-simplify-expr))))
1047 (and (eq (car-safe (nth 1 math-simplify-expr)) 'calcFunc-arccosh)
1048 math-living-dangerously
1049 (math-div (nth 1 (nth 1 math-simplify-expr))
1050 (list 'calcFunc-sqrt
1051 (math-sub (math-sqr (nth 1 (nth 1 math-simplify-expr))) 1))))
1052 (and (eq (car-safe (nth 1 math-simplify-expr)) 'calcFunc-arctanh)
1053 math-living-dangerously
1054 (math-div 1 (nth 1 (nth 1 math-simplify-expr))))))
1055
1056 (math-defsimplify calcFunc-arcsin
1057 (or (and (math-looks-negp (nth 1 math-simplify-expr))
1058 (math-neg (list 'calcFunc-arcsin (math-neg (nth 1 math-simplify-expr)))))
1059 (and (eq (nth 1 math-simplify-expr) 1)
1060 (math-quarter-circle t))
1061 (and (equal (nth 1 math-simplify-expr) '(frac 1 2))
1062 (math-div (math-half-circle t) 6))
1063 (and math-living-dangerously
1064 (eq (car-safe (nth 1 math-simplify-expr)) 'calcFunc-sin)
1065 (nth 1 (nth 1 math-simplify-expr)))
1066 (and math-living-dangerously
1067 (eq (car-safe (nth 1 math-simplify-expr)) 'calcFunc-cos)
1068 (math-sub (math-quarter-circle t)
1069 (nth 1 (nth 1 math-simplify-expr))))))
1070
1071 (math-defsimplify calcFunc-arccos
1072 (or (and (eq (nth 1 math-simplify-expr) 0)
1073 (math-quarter-circle t))
1074 (and (eq (nth 1 math-simplify-expr) -1)
1075 (math-half-circle t))
1076 (and (equal (nth 1 math-simplify-expr) '(frac 1 2))
1077 (math-div (math-half-circle t) 3))
1078 (and (equal (nth 1 math-simplify-expr) '(frac -1 2))
1079 (math-div (math-mul (math-half-circle t) 2) 3))
1080 (and math-living-dangerously
1081 (eq (car-safe (nth 1 math-simplify-expr)) 'calcFunc-cos)
1082 (nth 1 (nth 1 math-simplify-expr)))
1083 (and math-living-dangerously
1084 (eq (car-safe (nth 1 math-simplify-expr)) 'calcFunc-sin)
1085 (math-sub (math-quarter-circle t)
1086 (nth 1 (nth 1 math-simplify-expr))))))
1087
1088 (math-defsimplify calcFunc-arctan
1089 (or (and (math-looks-negp (nth 1 math-simplify-expr))
1090 (math-neg (list 'calcFunc-arctan (math-neg (nth 1 math-simplify-expr)))))
1091 (and (eq (nth 1 math-simplify-expr) 1)
1092 (math-div (math-half-circle t) 4))
1093 (and math-living-dangerously
1094 (eq (car-safe (nth 1 math-simplify-expr)) 'calcFunc-tan)
1095 (nth 1 (nth 1 math-simplify-expr)))))
1096
1097 (math-defsimplify calcFunc-arcsinh
1098 (or (and (math-looks-negp (nth 1 math-simplify-expr))
1099 (math-neg (list 'calcFunc-arcsinh (math-neg (nth 1 math-simplify-expr)))))
1100 (and (eq (car-safe (nth 1 math-simplify-expr)) 'calcFunc-sinh)
1101 (or math-living-dangerously
1102 (math-known-realp (nth 1 (nth 1 math-simplify-expr))))
1103 (nth 1 (nth 1 math-simplify-expr)))))
1104
1105 (math-defsimplify calcFunc-arccosh
1106 (and (eq (car-safe (nth 1 math-simplify-expr)) 'calcFunc-cosh)
1107 (or math-living-dangerously
1108 (math-known-realp (nth 1 (nth 1 math-simplify-expr))))
1109 (nth 1 (nth 1 math-simplify-expr))))
1110
1111 (math-defsimplify calcFunc-arctanh
1112 (or (and (math-looks-negp (nth 1 math-simplify-expr))
1113 (math-neg (list 'calcFunc-arctanh (math-neg (nth 1 math-simplify-expr)))))
1114 (and (eq (car-safe (nth 1 math-simplify-expr)) 'calcFunc-tanh)
1115 (or math-living-dangerously
1116 (math-known-realp (nth 1 (nth 1 math-simplify-expr))))
1117 (nth 1 (nth 1 math-simplify-expr)))))
1118
1119 (math-defsimplify calcFunc-sqrt
1120 (math-simplify-sqrt))
1121
1122 (defun math-simplify-sqrt ()
1123 (or (and (eq (car-safe (nth 1 math-simplify-expr)) 'frac)
1124 (math-div (list 'calcFunc-sqrt
1125 (math-mul (nth 1 (nth 1 math-simplify-expr))
1126 (nth 2 (nth 1 math-simplify-expr))))
1127 (nth 2 (nth 1 math-simplify-expr))))
1128 (let ((fac (if (math-objectp (nth 1 math-simplify-expr))
1129 (math-squared-factor (nth 1 math-simplify-expr))
1130 (math-common-constant-factor (nth 1 math-simplify-expr)))))
1131 (and fac (not (eq fac 1))
1132 (math-mul (math-normalize (list 'calcFunc-sqrt fac))
1133 (math-normalize
1134 (list 'calcFunc-sqrt
1135 (math-cancel-common-factor
1136 (nth 1 math-simplify-expr) fac))))))
1137 (and math-living-dangerously
1138 (or (and (eq (car-safe (nth 1 math-simplify-expr)) '-)
1139 (math-equal-int (nth 1 (nth 1 math-simplify-expr)) 1)
1140 (eq (car-safe (nth 2 (nth 1 math-simplify-expr))) '^)
1141 (math-equal-int (nth 2 (nth 2 (nth 1 math-simplify-expr))) 2)
1142 (or (and (eq (car-safe (nth 1 (nth 2 (nth 1 math-simplify-expr))))
1143 'calcFunc-sin)
1144 (list 'calcFunc-cos
1145 (nth 1 (nth 1 (nth 2 (nth 1 math-simplify-expr))))))
1146 (and (eq (car-safe (nth 1 (nth 2 (nth 1 math-simplify-expr))))
1147 'calcFunc-cos)
1148 (list 'calcFunc-sin
1149 (nth 1 (nth 1 (nth 2
1150 (nth 1 math-simplify-expr))))))))
1151 (and (eq (car-safe (nth 1 math-simplify-expr)) '-)
1152 (math-equal-int (nth 2 (nth 1 math-simplify-expr)) 1)
1153 (eq (car-safe (nth 1 (nth 1 math-simplify-expr))) '^)
1154 (math-equal-int (nth 2 (nth 1 (nth 1 math-simplify-expr))) 2)
1155 (and (eq (car-safe (nth 1 (nth 1 (nth 1 math-simplify-expr))))
1156 'calcFunc-cosh)
1157 (list 'calcFunc-sinh
1158 (nth 1 (nth 1 (nth 1 (nth 1 math-simplify-expr)))))))
1159 (and (eq (car-safe (nth 1 math-simplify-expr)) '+)
1160 (let ((a (nth 1 (nth 1 math-simplify-expr)))
1161 (b (nth 2 (nth 1 math-simplify-expr))))
1162 (and (or (and (math-equal-int a 1)
1163 (setq a b b (nth 1 (nth 1 math-simplify-expr))))
1164 (math-equal-int b 1))
1165 (eq (car-safe a) '^)
1166 (math-equal-int (nth 2 a) 2)
1167 (or (and (eq (car-safe (nth 1 a)) 'calcFunc-sinh)
1168 (list 'calcFunc-cosh (nth 1 (nth 1 a))))
1169 (and (eq (car-safe (nth 1 a)) 'calcFunc-csch)
1170 (list 'calcFunc-coth (nth 1 (nth 1 a))))
1171 (and (eq (car-safe (nth 1 a)) 'calcFunc-tan)
1172 (list '/ 1 (list 'calcFunc-cos
1173 (nth 1 (nth 1 a)))))
1174 (and (eq (car-safe (nth 1 a)) 'calcFunc-cot)
1175 (list '/ 1 (list 'calcFunc-sin
1176 (nth 1 (nth 1 a)))))))))
1177 (and (eq (car-safe (nth 1 math-simplify-expr)) '^)
1178 (list '^
1179 (nth 1 (nth 1 math-simplify-expr))
1180 (math-div (nth 2 (nth 1 math-simplify-expr)) 2)))
1181 (and (eq (car-safe (nth 1 math-simplify-expr)) 'calcFunc-sqrt)
1182 (list '^ (nth 1 (nth 1 math-simplify-expr)) (math-div 1 4)))
1183 (and (memq (car-safe (nth 1 math-simplify-expr)) '(* /))
1184 (list (car (nth 1 math-simplify-expr))
1185 (list 'calcFunc-sqrt (nth 1 (nth 1 math-simplify-expr)))
1186 (list 'calcFunc-sqrt (nth 2 (nth 1 math-simplify-expr)))))
1187 (and (memq (car-safe (nth 1 math-simplify-expr)) '(+ -))
1188 (not (math-any-floats (nth 1 math-simplify-expr)))
1189 (let ((f (calcFunc-factors (calcFunc-expand
1190 (nth 1 math-simplify-expr)))))
1191 (and (math-vectorp f)
1192 (or (> (length f) 2)
1193 (> (nth 2 (nth 1 f)) 1))
1194 (let ((out 1) (rest 1) (sums 1) fac pow)
1195 (while (setq f (cdr f))
1196 (setq fac (nth 1 (car f))
1197 pow (nth 2 (car f)))
1198 (if (> pow 1)
1199 (setq out (math-mul out (math-pow
1200 fac (/ pow 2)))
1201 pow (% pow 2)))
1202 (if (> pow 0)
1203 (if (memq (car-safe fac) '(+ -))
1204 (setq sums (math-mul-thru sums fac))
1205 (setq rest (math-mul rest fac)))))
1206 (and (not (and (eq out 1) (memq rest '(1 -1))))
1207 (math-mul
1208 out
1209 (list 'calcFunc-sqrt
1210 (math-mul sums rest))))))))))))
1211
1212 ;;; Rather than factoring x into primes, just check for the first ten primes.
1213 (defun math-squared-factor (x)
1214 (if (Math-integerp x)
1215 (let ((prsqr '(4 9 25 49 121 169 289 361 529 841))
1216 (fac 1)
1217 res)
1218 (while prsqr
1219 (if (eq (cdr (setq res (math-idivmod x (car prsqr)))) 0)
1220 (setq x (car res)
1221 fac (math-mul fac (car prsqr)))
1222 (setq prsqr (cdr prsqr))))
1223 fac)))
1224
1225 (math-defsimplify calcFunc-exp
1226 (math-simplify-exp (nth 1 math-simplify-expr)))
1227
1228 (defun math-simplify-exp (x)
1229 (or (and (eq (car-safe x) 'calcFunc-ln)
1230 (nth 1 x))
1231 (and math-living-dangerously
1232 (or (and (eq (car-safe x) 'calcFunc-arcsinh)
1233 (math-add (nth 1 x)
1234 (list 'calcFunc-sqrt
1235 (math-add (math-sqr (nth 1 x)) 1))))
1236 (and (eq (car-safe x) 'calcFunc-arccosh)
1237 (math-add (nth 1 x)
1238 (list 'calcFunc-sqrt
1239 (math-sub (math-sqr (nth 1 x)) 1))))
1240 (and (eq (car-safe x) 'calcFunc-arctanh)
1241 (math-div (list 'calcFunc-sqrt (math-add 1 (nth 1 x)))
1242 (list 'calcFunc-sqrt (math-sub 1 (nth 1 x)))))
1243 (let ((m (math-should-expand-trig x 'exp)))
1244 (and m (integerp (car m))
1245 (list '^ (list 'calcFunc-exp (nth 1 m)) (car m))))))
1246 (and calc-symbolic-mode
1247 (math-known-imagp x)
1248 (let* ((ip (calcFunc-im x))
1249 (n (math-linear-in ip '(var pi var-pi)))
1250 s c)
1251 (and n
1252 (setq s (math-known-sin (car n) (nth 1 n) 120 0))
1253 (setq c (math-known-sin (car n) (nth 1 n) 120 300))
1254 (list '+ c (list '* s '(var i var-i))))))))
1255
1256 (math-defsimplify calcFunc-ln
1257 (or (and (eq (car-safe (nth 1 math-simplify-expr)) 'calcFunc-exp)
1258 (or math-living-dangerously
1259 (math-known-realp (nth 1 (nth 1 math-simplify-expr))))
1260 (nth 1 (nth 1 math-simplify-expr)))
1261 (and (eq (car-safe (nth 1 math-simplify-expr)) '^)
1262 (equal (nth 1 (nth 1 math-simplify-expr)) '(var e var-e))
1263 (or math-living-dangerously
1264 (math-known-realp (nth 2 (nth 1 math-simplify-expr))))
1265 (nth 2 (nth 1 math-simplify-expr)))
1266 (and calc-symbolic-mode
1267 (math-known-negp (nth 1 math-simplify-expr))
1268 (math-add (list 'calcFunc-ln (math-neg (nth 1 math-simplify-expr)))
1269 '(* (var pi var-pi) (var i var-i))))
1270 (and calc-symbolic-mode
1271 (math-known-imagp (nth 1 math-simplify-expr))
1272 (let* ((ip (calcFunc-im (nth 1 math-simplify-expr)))
1273 (ips (math-possible-signs ip)))
1274 (or (and (memq ips '(4 6))
1275 (math-add (list 'calcFunc-ln ip)
1276 '(/ (* (var pi var-pi) (var i var-i)) 2)))
1277 (and (memq ips '(1 3))
1278 (math-sub (list 'calcFunc-ln (math-neg ip))
1279 '(/ (* (var pi var-pi) (var i var-i)) 2))))))))
1280
1281 (math-defsimplify ^
1282 (math-simplify-pow))
1283
1284 (defun math-simplify-pow ()
1285 (or (and math-living-dangerously
1286 (or (and (eq (car-safe (nth 1 math-simplify-expr)) '^)
1287 (list '^
1288 (nth 1 (nth 1 math-simplify-expr))
1289 (math-mul (nth 2 math-simplify-expr)
1290 (nth 2 (nth 1 math-simplify-expr)))))
1291 (and (eq (car-safe (nth 1 math-simplify-expr)) 'calcFunc-sqrt)
1292 (list '^
1293 (nth 1 (nth 1 math-simplify-expr))
1294 (math-div (nth 2 math-simplify-expr) 2)))
1295 (and (memq (car-safe (nth 1 math-simplify-expr)) '(* /))
1296 (list (car (nth 1 math-simplify-expr))
1297 (list '^ (nth 1 (nth 1 math-simplify-expr))
1298 (nth 2 math-simplify-expr))
1299 (list '^ (nth 2 (nth 1 math-simplify-expr))
1300 (nth 2 math-simplify-expr))))))
1301 (and (math-equal-int (nth 1 math-simplify-expr) 10)
1302 (eq (car-safe (nth 2 math-simplify-expr)) 'calcFunc-log10)
1303 (nth 1 (nth 2 math-simplify-expr)))
1304 (and (equal (nth 1 math-simplify-expr) '(var e var-e))
1305 (math-simplify-exp (nth 2 math-simplify-expr)))
1306 (and (eq (car-safe (nth 1 math-simplify-expr)) 'calcFunc-exp)
1307 (not math-integrating)
1308 (list 'calcFunc-exp (math-mul (nth 1 (nth 1 math-simplify-expr))
1309 (nth 2 math-simplify-expr))))
1310 (and (equal (nth 1 math-simplify-expr) '(var i var-i))
1311 (math-imaginary-i)
1312 (math-num-integerp (nth 2 math-simplify-expr))
1313 (let ((x (math-mod (math-trunc (nth 2 math-simplify-expr)) 4)))
1314 (cond ((eq x 0) 1)
1315 ((eq x 1) (nth 1 math-simplify-expr))
1316 ((eq x 2) -1)
1317 ((eq x 3) (math-neg (nth 1 math-simplify-expr))))))
1318 (and math-integrating
1319 (integerp (nth 2 math-simplify-expr))
1320 (>= (nth 2 math-simplify-expr) 2)
1321 (or (and (eq (car-safe (nth 1 math-simplify-expr)) 'calcFunc-cos)
1322 (math-mul (math-pow (nth 1 math-simplify-expr)
1323 (- (nth 2 math-simplify-expr) 2))
1324 (math-sub 1
1325 (math-sqr
1326 (list 'calcFunc-sin
1327 (nth 1 (nth 1 math-simplify-expr)))))))
1328 (and (eq (car-safe (nth 1 math-simplify-expr)) 'calcFunc-cosh)
1329 (math-mul (math-pow (nth 1 math-simplify-expr)
1330 (- (nth 2 math-simplify-expr) 2))
1331 (math-add 1
1332 (math-sqr
1333 (list 'calcFunc-sinh
1334 (nth 1 (nth 1 math-simplify-expr)))))))))
1335 (and (eq (car-safe (nth 2 math-simplify-expr)) 'frac)
1336 (Math-ratp (nth 1 math-simplify-expr))
1337 (Math-posp (nth 1 math-simplify-expr))
1338 (if (equal (nth 2 math-simplify-expr) '(frac 1 2))
1339 (list 'calcFunc-sqrt (nth 1 math-simplify-expr))
1340 (let ((flr (math-floor (nth 2 math-simplify-expr))))
1341 (and (not (Math-zerop flr))
1342 (list '* (list '^ (nth 1 math-simplify-expr) flr)
1343 (list '^ (nth 1 math-simplify-expr)
1344 (math-sub (nth 2 math-simplify-expr) flr)))))))
1345 (and (eq (math-quarter-integer (nth 2 math-simplify-expr)) 2)
1346 (let ((temp (math-simplify-sqrt)))
1347 (and temp
1348 (list '^ temp (math-mul (nth 2 math-simplify-expr) 2)))))))
1349
1350 (math-defsimplify calcFunc-log10
1351 (and (eq (car-safe (nth 1 math-simplify-expr)) '^)
1352 (math-equal-int (nth 1 (nth 1 math-simplify-expr)) 10)
1353 (or math-living-dangerously
1354 (math-known-realp (nth 2 (nth 1 math-simplify-expr))))
1355 (nth 2 (nth 1 math-simplify-expr))))
1356
1357
1358 (math-defsimplify calcFunc-erf
1359 (or (and (math-looks-negp (nth 1 math-simplify-expr))
1360 (math-neg (list 'calcFunc-erf (math-neg (nth 1 math-simplify-expr)))))
1361 (and (eq (car-safe (nth 1 math-simplify-expr)) 'calcFunc-conj)
1362 (list 'calcFunc-conj
1363 (list 'calcFunc-erf (nth 1 (nth 1 math-simplify-expr)))))))
1364
1365 (math-defsimplify calcFunc-erfc
1366 (or (and (math-looks-negp (nth 1 math-simplify-expr))
1367 (math-sub 2 (list 'calcFunc-erfc (math-neg (nth 1 math-simplify-expr)))))
1368 (and (eq (car-safe (nth 1 math-simplify-expr)) 'calcFunc-conj)
1369 (list 'calcFunc-conj
1370 (list 'calcFunc-erfc (nth 1 (nth 1 math-simplify-expr)))))))
1371
1372
1373 (defun math-linear-in (expr term &optional always)
1374 (if (math-expr-contains expr term)
1375 (let* ((calc-prefer-frac t)
1376 (p (math-is-polynomial expr term 1)))
1377 (and (cdr p)
1378 p))
1379 (and always (list expr 0))))
1380
1381 (defun math-multiple-of (expr term)
1382 (let ((p (math-linear-in expr term)))
1383 (and p
1384 (math-zerop (car p))
1385 (nth 1 p))))
1386
1387 ; not perfect, but it'll do
1388 (defun math-integer-plus (expr)
1389 (cond ((Math-integerp expr)
1390 (list 0 expr))
1391 ((and (memq (car expr) '(+ -))
1392 (Math-integerp (nth 1 expr)))
1393 (list (if (eq (car expr) '+) (nth 2 expr) (math-neg (nth 2 expr)))
1394 (nth 1 expr)))
1395 ((and (memq (car expr) '(+ -))
1396 (Math-integerp (nth 2 expr)))
1397 (list (nth 1 expr)
1398 (if (eq (car expr) '+) (nth 2 expr) (math-neg (nth 2 expr)))))
1399 (t nil)))
1400
1401 (defun math-is-linear (expr &optional always)
1402 (let ((offset nil)
1403 (coef nil))
1404 (if (eq (car-safe expr) '+)
1405 (if (Math-objectp (nth 1 expr))
1406 (setq offset (nth 1 expr)
1407 expr (nth 2 expr))
1408 (if (Math-objectp (nth 2 expr))
1409 (setq offset (nth 2 expr)
1410 expr (nth 1 expr))))
1411 (if (eq (car-safe expr) '-)
1412 (if (Math-objectp (nth 1 expr))
1413 (setq offset (nth 1 expr)
1414 expr (math-neg (nth 2 expr)))
1415 (if (Math-objectp (nth 2 expr))
1416 (setq offset (math-neg (nth 2 expr))
1417 expr (nth 1 expr))))))
1418 (setq coef (math-is-multiple expr always))
1419 (if offset
1420 (list offset (or (car coef) 1) (or (nth 1 coef) expr))
1421 (if coef
1422 (cons 0 coef)))))
1423
1424 (defun math-is-multiple (expr &optional always)
1425 (or (if (eq (car-safe expr) '*)
1426 (if (Math-objectp (nth 1 expr))
1427 (list (nth 1 expr) (nth 2 expr)))
1428 (if (eq (car-safe expr) '/)
1429 (if (and (Math-objectp (nth 1 expr))
1430 (not (math-equal-int (nth 1 expr) 1)))
1431 (list (nth 1 expr) (math-div 1 (nth 2 expr)))
1432 (if (Math-objectp (nth 2 expr))
1433 (list (math-div 1 (nth 2 expr)) (nth 1 expr))
1434 (let ((res (math-is-multiple (nth 1 expr))))
1435 (if res
1436 (list (car res)
1437 (math-div (nth 2 (nth 1 expr)) (nth 2 expr)))
1438 (setq res (math-is-multiple (nth 2 expr)))
1439 (if res
1440 (list (math-div 1 (car res))
1441 (math-div (nth 1 expr)
1442 (nth 2 (nth 2 expr)))))))))
1443 (if (eq (car-safe expr) 'neg)
1444 (list -1 (nth 1 expr)))))
1445 (if (Math-objvecp expr)
1446 (and (eq always 1)
1447 (list expr 1))
1448 (and always
1449 (list 1 expr)))))
1450
1451 (defun calcFunc-lin (expr &optional var)
1452 (if var
1453 (let ((res (math-linear-in expr var t)))
1454 (or res (math-reject-arg expr "Linear term expected"))
1455 (list 'vec (car res) (nth 1 res) var))
1456 (let ((res (math-is-linear expr t)))
1457 (or res (math-reject-arg expr "Linear term expected"))
1458 (cons 'vec res))))
1459
1460 (defun calcFunc-linnt (expr &optional var)
1461 (if var
1462 (let ((res (math-linear-in expr var)))
1463 (or res (math-reject-arg expr "Linear term expected"))
1464 (list 'vec (car res) (nth 1 res) var))
1465 (let ((res (math-is-linear expr)))
1466 (or res (math-reject-arg expr "Linear term expected"))
1467 (cons 'vec res))))
1468
1469 (defun calcFunc-islin (expr &optional var)
1470 (if (and (Math-objvecp expr) (not var))
1471 0
1472 (calcFunc-lin expr var)
1473 1))
1474
1475 (defun calcFunc-islinnt (expr &optional var)
1476 (if (Math-objvecp expr)
1477 0
1478 (calcFunc-linnt expr var)
1479 1))
1480
1481
1482
1483
1484 ;;; Simple operations on expressions.
1485
1486 ;;; Return number of occurrences of thing in expr, or nil if none.
1487 (defun math-expr-contains-count (expr thing)
1488 (cond ((equal expr thing) 1)
1489 ((Math-primp expr) nil)
1490 (t
1491 (let ((num 0))
1492 (while (setq expr (cdr expr))
1493 (setq num (+ num (or (math-expr-contains-count
1494 (car expr) thing) 0))))
1495 (and (> num 0)
1496 num)))))
1497
1498 (defun math-expr-contains (expr thing)
1499 (cond ((equal expr thing) 1)
1500 ((Math-primp expr) nil)
1501 (t
1502 (while (and (setq expr (cdr expr))
1503 (not (math-expr-contains (car expr) thing))))
1504 expr)))
1505
1506 ;;; Return non-nil if any variable of thing occurs in expr.
1507 (defun math-expr-depends (expr thing)
1508 (if (Math-primp thing)
1509 (and (eq (car-safe thing) 'var)
1510 (math-expr-contains expr thing))
1511 (while (and (setq thing (cdr thing))
1512 (not (math-expr-depends expr (car thing)))))
1513 thing))
1514
1515 ;;; Substitute all occurrences of old for new in expr (non-destructive).
1516
1517 ;; The variables math-expr-subst-old and math-expr-subst-new are local
1518 ;; for math-expr-subst, but used by math-expr-subst-rec.
1519 (defvar math-expr-subst-old)
1520 (defvar math-expr-subst-new)
1521
1522 (defun math-expr-subst (expr math-expr-subst-old math-expr-subst-new)
1523 (math-expr-subst-rec expr))
1524
1525 (defalias 'calcFunc-subst 'math-expr-subst)
1526
1527 (defun math-expr-subst-rec (expr)
1528 (cond ((equal expr math-expr-subst-old) math-expr-subst-new)
1529 ((Math-primp expr) expr)
1530 ((memq (car expr) '(calcFunc-deriv
1531 calcFunc-tderiv))
1532 (if (= (length expr) 2)
1533 (if (equal (nth 1 expr) math-expr-subst-old)
1534 (append expr (list math-expr-subst-new))
1535 expr)
1536 (list (car expr) (nth 1 expr)
1537 (math-expr-subst-rec (nth 2 expr)))))
1538 (t
1539 (cons (car expr)
1540 (mapcar 'math-expr-subst-rec (cdr expr))))))
1541
1542 ;;; Various measures of the size of an expression.
1543 (defun math-expr-weight (expr)
1544 (if (Math-primp expr)
1545 1
1546 (let ((w 1))
1547 (while (setq expr (cdr expr))
1548 (setq w (+ w (math-expr-weight (car expr)))))
1549 w)))
1550
1551 (defun math-expr-height (expr)
1552 (if (Math-primp expr)
1553 0
1554 (let ((h 0))
1555 (while (setq expr (cdr expr))
1556 (setq h (max h (math-expr-height (car expr)))))
1557 (1+ h))))
1558
1559
1560
1561
1562 ;;; Polynomial operations (to support the integrator and solve-for).
1563
1564 (defun calcFunc-collect (expr base)
1565 (let ((p (math-is-polynomial expr base 50 t)))
1566 (if (cdr p)
1567 (math-normalize ; fix selection bug
1568 (math-build-polynomial-expr p base))
1569 expr)))
1570
1571 ;;; If expr is of the form "a + bx + cx^2 + ...", return the list (a b c ...),
1572 ;;; else return nil if not in polynomial form. If "loose" (math-is-poly-loose),
1573 ;;; coefficients may contain x, e.g., sin(x) + cos(x) x^2 is a loose polynomial in x.
1574
1575 ;; The variables math-is-poly-degree and math-is-poly-loose are local to
1576 ;; math-is-polynomial, but are used by math-is-poly-rec
1577 (defvar math-is-poly-degree)
1578 (defvar math-is-poly-loose)
1579
1580 (defun math-is-polynomial (expr var &optional math-is-poly-degree math-is-poly-loose)
1581 (let* ((math-poly-base-variable (if math-is-poly-loose
1582 (if (eq math-is-poly-loose 'gen) var '(var XXX XXX))
1583 math-poly-base-variable))
1584 (poly (math-is-poly-rec expr math-poly-neg-powers)))
1585 (and (or (null math-is-poly-degree)
1586 (<= (length poly) (1+ math-is-poly-degree)))
1587 poly)))
1588
1589 (defun math-is-poly-rec (expr negpow)
1590 (math-poly-simplify
1591 (or (cond ((or (equal expr var)
1592 (eq (car-safe expr) '^))
1593 (let ((pow 1)
1594 (expr expr))
1595 (or (equal expr var)
1596 (setq pow (nth 2 expr)
1597 expr (nth 1 expr)))
1598 (or (eq math-poly-mult-powers 1)
1599 (setq pow (let ((m (math-is-multiple pow 1)))
1600 (and (eq (car-safe (car m)) 'cplx)
1601 (Math-zerop (nth 1 (car m)))
1602 (setq m (list (nth 2 (car m))
1603 (math-mul (nth 1 m)
1604 '(var i var-i)))))
1605 (and (if math-poly-mult-powers
1606 (equal math-poly-mult-powers
1607 (nth 1 m))
1608 (setq math-poly-mult-powers (nth 1 m)))
1609 (or (equal expr var)
1610 (eq math-poly-mult-powers 1))
1611 (car m)))))
1612 (if (consp pow)
1613 (progn
1614 (setq pow (math-to-simple-fraction pow))
1615 (and (eq (car-safe pow) 'frac)
1616 math-poly-frac-powers
1617 (equal expr var)
1618 (setq math-poly-frac-powers
1619 (calcFunc-lcm math-poly-frac-powers
1620 (nth 2 pow))))))
1621 (or (memq math-poly-frac-powers '(1 nil))
1622 (setq pow (math-mul pow math-poly-frac-powers)))
1623 (if (integerp pow)
1624 (if (and (= pow 1)
1625 (equal expr var))
1626 (list 0 1)
1627 (if (natnump pow)
1628 (let ((p1 (if (equal expr var)
1629 (list 0 1)
1630 (math-is-poly-rec expr nil)))
1631 (n pow)
1632 (accum (list 1)))
1633 (and p1
1634 (or (null math-is-poly-degree)
1635 (<= (* (1- (length p1)) n) math-is-poly-degree))
1636 (progn
1637 (while (>= n 1)
1638 (setq accum (math-poly-mul accum p1)
1639 n (1- n)))
1640 accum)))
1641 (and negpow
1642 (math-is-poly-rec expr nil)
1643 (setq math-poly-neg-powers
1644 (cons (math-pow expr (- pow))
1645 math-poly-neg-powers))
1646 (list (list '^ expr pow))))))))
1647 ((Math-objectp expr)
1648 (list expr))
1649 ((memq (car expr) '(+ -))
1650 (let ((p1 (math-is-poly-rec (nth 1 expr) negpow)))
1651 (and p1
1652 (let ((p2 (math-is-poly-rec (nth 2 expr) negpow)))
1653 (and p2
1654 (math-poly-mix p1 1 p2
1655 (if (eq (car expr) '+) 1 -1)))))))
1656 ((eq (car expr) 'neg)
1657 (mapcar 'math-neg (math-is-poly-rec (nth 1 expr) negpow)))
1658 ((eq (car expr) '*)
1659 (let ((p1 (math-is-poly-rec (nth 1 expr) negpow)))
1660 (and p1
1661 (let ((p2 (math-is-poly-rec (nth 2 expr) negpow)))
1662 (and p2
1663 (or (null math-is-poly-degree)
1664 (<= (- (+ (length p1) (length p2)) 2)
1665 math-is-poly-degree))
1666 (math-poly-mul p1 p2))))))
1667 ((eq (car expr) '/)
1668 (and (or (not (math-poly-depends (nth 2 expr) var))
1669 (and negpow
1670 (math-is-poly-rec (nth 2 expr) nil)
1671 (setq math-poly-neg-powers
1672 (cons (nth 2 expr) math-poly-neg-powers))))
1673 (not (Math-zerop (nth 2 expr)))
1674 (let ((p1 (math-is-poly-rec (nth 1 expr) negpow)))
1675 (mapcar (function (lambda (x) (math-div x (nth 2 expr))))
1676 p1))))
1677 ((and (eq (car expr) 'calcFunc-exp)
1678 (equal var '(var e var-e)))
1679 (math-is-poly-rec (list '^ var (nth 1 expr)) negpow))
1680 ((and (eq (car expr) 'calcFunc-sqrt)
1681 math-poly-frac-powers)
1682 (math-is-poly-rec (list '^ (nth 1 expr) '(frac 1 2)) negpow))
1683 (t nil))
1684 (and (or (not (math-poly-depends expr var))
1685 math-is-poly-loose)
1686 (not (eq (car expr) 'vec))
1687 (list expr)))))
1688
1689 ;;; Check if expr is a polynomial in var; if so, return its degree.
1690 (defun math-polynomial-p (expr var)
1691 (cond ((equal expr var) 1)
1692 ((Math-primp expr) 0)
1693 ((memq (car expr) '(+ -))
1694 (let ((p1 (math-polynomial-p (nth 1 expr) var))
1695 p2)
1696 (and p1 (setq p2 (math-polynomial-p (nth 2 expr) var))
1697 (max p1 p2))))
1698 ((eq (car expr) '*)
1699 (let ((p1 (math-polynomial-p (nth 1 expr) var))
1700 p2)
1701 (and p1 (setq p2 (math-polynomial-p (nth 2 expr) var))
1702 (+ p1 p2))))
1703 ((eq (car expr) 'neg)
1704 (math-polynomial-p (nth 1 expr) var))
1705 ((and (eq (car expr) '/)
1706 (not (math-poly-depends (nth 2 expr) var)))
1707 (math-polynomial-p (nth 1 expr) var))
1708 ((and (eq (car expr) '^)
1709 (natnump (nth 2 expr)))
1710 (let ((p1 (math-polynomial-p (nth 1 expr) var)))
1711 (and p1 (* p1 (nth 2 expr)))))
1712 ((math-poly-depends expr var) nil)
1713 (t 0)))
1714
1715 (defun math-poly-depends (expr var)
1716 (if math-poly-base-variable
1717 (math-expr-contains expr math-poly-base-variable)
1718 (math-expr-depends expr var)))
1719
1720 ;;; Find the variable (or sub-expression) which is the base of polynomial expr.
1721 ;; The variables math-poly-base-const-ok and math-poly-base-pred are
1722 ;; local to math-polynomial-base, but are used by math-polynomial-base-rec.
1723 (defvar math-poly-base-const-ok)
1724 (defvar math-poly-base-pred)
1725
1726 ;; The variable math-poly-base-top-expr is local to math-polynomial-base,
1727 ;; but is used by math-polynomial-p1 in calc-poly.el, which is called
1728 ;; by math-polynomial-base.
1729
1730 (defun math-polynomial-base (math-poly-base-top-expr &optional math-poly-base-pred)
1731 (or math-poly-base-pred
1732 (setq math-poly-base-pred (function (lambda (base) (math-polynomial-p
1733 math-poly-base-top-expr base)))))
1734 (or (let ((math-poly-base-const-ok nil))
1735 (math-polynomial-base-rec math-poly-base-top-expr))
1736 (let ((math-poly-base-const-ok t))
1737 (math-polynomial-base-rec math-poly-base-top-expr))))
1738
1739 (defun math-polynomial-base-rec (mpb-expr)
1740 (and (not (Math-objvecp mpb-expr))
1741 (or (and (memq (car mpb-expr) '(+ - *))
1742 (or (math-polynomial-base-rec (nth 1 mpb-expr))
1743 (math-polynomial-base-rec (nth 2 mpb-expr))))
1744 (and (memq (car mpb-expr) '(/ neg))
1745 (math-polynomial-base-rec (nth 1 mpb-expr)))
1746 (and (eq (car mpb-expr) '^)
1747 (math-polynomial-base-rec (nth 1 mpb-expr)))
1748 (and (eq (car mpb-expr) 'calcFunc-exp)
1749 (math-polynomial-base-rec '(var e var-e)))
1750 (and (or math-poly-base-const-ok (math-expr-contains-vars mpb-expr))
1751 (funcall math-poly-base-pred mpb-expr)
1752 mpb-expr))))
1753
1754 ;;; Return non-nil if expr refers to any variables.
1755 (defun math-expr-contains-vars (expr)
1756 (or (eq (car-safe expr) 'var)
1757 (and (not (Math-primp expr))
1758 (progn
1759 (while (and (setq expr (cdr expr))
1760 (not (math-expr-contains-vars (car expr)))))
1761 expr))))
1762
1763 ;;; Simplify a polynomial in list form by stripping off high-end zeros.
1764 ;;; This always leaves the constant part, i.e., nil->nil and nonnil->nonnil.
1765 (defun math-poly-simplify (p)
1766 (and p
1767 (if (Math-zerop (nth (1- (length p)) p))
1768 (let ((pp (copy-sequence p)))
1769 (while (and (cdr pp)
1770 (Math-zerop (nth (1- (length pp)) pp)))
1771 (setcdr (nthcdr (- (length pp) 2) pp) nil))
1772 pp)
1773 p)))
1774
1775 ;;; Compute ac*a + bc*b for polynomials in list form a, b and
1776 ;;; coefficients ac, bc. Result may be unsimplified.
1777 (defun math-poly-mix (a ac b bc)
1778 (and (or a b)
1779 (cons (math-add (math-mul (or (car a) 0) ac)
1780 (math-mul (or (car b) 0) bc))
1781 (math-poly-mix (cdr a) ac (cdr b) bc))))
1782
1783 (defun math-poly-zerop (a)
1784 (or (null a)
1785 (and (null (cdr a)) (Math-zerop (car a)))))
1786
1787 ;;; Multiply two polynomials in list form.
1788 (defun math-poly-mul (a b)
1789 (and a b
1790 (math-poly-mix b (car a)
1791 (math-poly-mul (cdr a) (cons 0 b)) 1)))
1792
1793 ;;; Build an expression from a polynomial list.
1794 (defun math-build-polynomial-expr (p var)
1795 (if p
1796 (if (Math-numberp var)
1797 (math-with-extra-prec 1
1798 (let* ((rp (reverse p))
1799 (accum (car rp)))
1800 (while (setq rp (cdr rp))
1801 (setq accum (math-add (car rp) (math-mul accum var))))
1802 accum))
1803 (let* ((rp (reverse p))
1804 (n (1- (length rp)))
1805 (accum (math-mul (car rp) (math-pow var n)))
1806 term)
1807 (while (setq rp (cdr rp))
1808 (setq n (1- n))
1809 (or (math-zerop (car rp))
1810 (setq accum (list (if (math-looks-negp (car rp)) '- '+)
1811 accum
1812 (math-mul (if (math-looks-negp (car rp))
1813 (math-neg (car rp))
1814 (car rp))
1815 (math-pow var n))))))
1816 accum))
1817 0))
1818
1819
1820 (defun math-to-simple-fraction (f)
1821 (or (and (eq (car-safe f) 'float)
1822 (or (and (>= (nth 2 f) 0)
1823 (math-scale-int (nth 1 f) (nth 2 f)))
1824 (and (integerp (nth 1 f))
1825 (> (nth 1 f) -1000)
1826 (< (nth 1 f) 1000)
1827 (math-make-frac (nth 1 f)
1828 (math-scale-int 1 (- (nth 2 f)))))))
1829 f))
1830
1831 (provide 'calc-alg)
1832
1833 ;;; arch-tag: 52e7dcdf-9688-464d-a02b-4bbe789348d0
1834 ;;; calc-alg.el ends here