1 ;;; calc-stat.el --- statistical functions for Calc
3 ;; Copyright (C) 1990, 1991, 1992, 1993, 2001 Free Software Foundation, Inc.
5 ;; Author: David Gillespie <daveg@synaptics.com>
6 ;; Maintainer: Colin Walters <walters@debian.org>
8 ;; This file is part of GNU Emacs.
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.
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.
29 ;; This file is autoloaded from calc-ext.el.
34 (defun calc-Need-calc-stat () nil)
37 ;;; Statistical operations on vectors.
39 (defun calc-vector-count (arg)
42 (calc-vector-op "coun" 'calcFunc-vcount arg)))
44 (defun calc-vector-sum (arg)
47 (if (calc-is-hyperbolic)
48 (calc-vector-op "vprd" 'calcFunc-vprod arg)
49 (calc-vector-op "vsum" 'calcFunc-vsum arg))))
51 (defun calc-vector-product (arg)
53 (calc-hyperbolic-func)
54 (calc-vector-sum arg))
56 (defun calc-vector-max (arg)
60 (calc-vector-op "vmin" 'calcFunc-vmin arg)
61 (calc-vector-op "vmax" 'calcFunc-vmax arg))))
63 (defun calc-vector-min (arg)
66 (calc-vector-max arg))
68 (defun calc-vector-mean (arg)
71 (if (calc-is-hyperbolic)
73 (calc-vector-op "harm" 'calcFunc-vhmean arg)
74 (calc-vector-op "medn" 'calcFunc-vmedian arg))
76 (calc-vector-op "meae" 'calcFunc-vmeane arg)
77 (calc-vector-op "mean" 'calcFunc-vmean arg)))))
79 (defun calc-vector-mean-error (arg)
82 (calc-vector-mean arg))
84 (defun calc-vector-median (arg)
86 (calc-hyperbolic-func)
87 (calc-vector-mean arg))
89 (defun calc-vector-harmonic-mean (arg)
92 (calc-hyperbolic-func)
93 (calc-vector-mean arg))
95 (defun calc-vector-geometric-mean (arg)
98 (if (calc-is-hyperbolic)
99 (calc-binary-op "geom" 'calcFunc-agmean arg)
100 (calc-vector-op "geom" 'calcFunc-vgmean arg))))
102 (defun calc-vector-sdev (arg)
105 (if (calc-is-hyperbolic)
106 (if (calc-is-inverse)
107 (calc-vector-op "pvar" 'calcFunc-vpvar arg)
108 (calc-vector-op "var" 'calcFunc-vvar arg))
109 (if (calc-is-inverse)
110 (calc-vector-op "psdv" 'calcFunc-vpsdev arg)
111 (calc-vector-op "sdev" 'calcFunc-vsdev arg)))))
113 (defun calc-vector-pop-sdev (arg)
116 (calc-vector-sdev arg))
118 (defun calc-vector-variance (arg)
120 (calc-hyperbolic-func)
121 (calc-vector-sdev arg))
123 (defun calc-vector-pop-variance (arg)
126 (calc-hyperbolic-func)
127 (calc-vector-sdev arg))
129 (defun calc-vector-covariance (arg)
132 (let ((n (if (eq arg 1) 1 2)))
133 (if (calc-is-hyperbolic)
134 (calc-enter-result n "corr" (cons 'calcFunc-vcorr
135 (calc-top-list-n n)))
136 (if (calc-is-inverse)
137 (calc-enter-result n "pcov" (cons 'calcFunc-vpcov
138 (calc-top-list-n n)))
139 (calc-enter-result n "cov" (cons 'calcFunc-vcov
140 (calc-top-list-n n))))))))
142 (defun calc-vector-pop-covariance (arg)
145 (calc-vector-covariance arg))
147 (defun calc-vector-correlation (arg)
149 (calc-hyperbolic-func)
150 (calc-vector-covariance arg))
152 (defun calc-vector-op (name func arg)
153 (setq calc-aborted-prefix name
154 arg (prefix-numeric-value arg))
156 (error "Negative arguments not allowed"))
157 (calc-enter-result arg name (cons func (calc-top-list-n arg))))
162 ;;; Useful statistical functions
164 ;;; Sum, product, etc., of one or more values or vectors.
165 ;;; Each argument must be either a number or a vector. Vectors
166 ;;; are flattened, but variables inside are assumed to represent
169 (defun calcFunc-vsum (&rest vecs)
170 (math-reduce-many-vecs 'calcFunc-add 'calcFunc-vsum vecs 0))
172 (defun calcFunc-vprod (&rest vecs)
173 (math-reduce-many-vecs 'calcFunc-mul 'calcFunc-vprod vecs 1))
175 (defun calcFunc-vmax (&rest vecs)
176 (if (eq (car-safe (car vecs)) 'sdev)
178 (if (eq (car-safe (car vecs)) 'intv)
179 (nth 3 (math-fix-int-intv (car vecs)))
180 (math-reduce-many-vecs 'calcFunc-max 'calcFunc-vmax vecs
181 '(neg (var inf var-inf))))))
183 (defun calcFunc-vmin (&rest vecs)
184 (if (eq (car-safe (car vecs)) 'sdev)
185 '(neg (var inf var-inf))
186 (if (eq (car-safe (car vecs)) 'intv)
187 (nth 2 (math-fix-int-intv (car vecs)))
188 (math-reduce-many-vecs 'calcFunc-min 'calcFunc-vmin vecs
189 '(var inf var-inf)))))
191 (defun math-reduce-many-vecs (func whole-func vecs ident)
192 (let ((const-part nil)
195 (let ((calc-internal-prec (+ calc-internal-prec 2)))
197 (setq val (car vecs))
198 (and (eq (car-safe val) 'var)
199 (eq (car-safe (calc-var-value (nth 2 val))) 'vec)
200 (setq val (symbol-value (nth 2 val))))
201 (cond ((Math-vectorp val)
202 (setq vec (append (and const-part (list const-part))
203 (math-flatten-vector val)))
204 (setq const-part (if vec
206 (math-calcFunc-to-var func)
209 ((or (Math-objectp val) (math-infinitep val))
210 (setq const-part (if const-part
211 (funcall func const-part val)
214 (setq symb-part (nconc symb-part (list val)))))
215 (setq vecs (cdr vecs))))
218 (setq const-part (math-normalize const-part))
220 (funcall func const-part (cons whole-func symb-part))
222 (if symb-part (cons whole-func symb-part) ident))))
225 ;;; Return the number of data elements among the arguments.
226 (defun calcFunc-vcount (&rest vecs)
229 (setq count (if (Math-vectorp (car vecs))
230 (+ count (math-count-elements (car vecs)))
231 (if (Math-objectp (car vecs))
233 (if (and (eq (car-safe (car vecs)) 'var)
234 (eq (car-safe (calc-var-value
237 (+ count (math-count-elements
238 (symbol-value (nth 2 (car vecs)))))
239 (math-reject-arg (car vecs) 'numvecp))))
243 (defun math-count-elements (vec)
245 (while (setq vec (cdr vec))
246 (setq count (if (Math-vectorp (car vec))
247 (+ count (math-count-elements (car vec)))
252 (defun math-flatten-many-vecs (vecs)
257 (if (Math-vectorp (car p))
258 (math-flatten-vector (car p))
259 (if (Math-objectp (car p))
261 (if (and (eq (car-safe (car p)) 'var)
262 (eq (car-safe (calc-var-value
263 (nth 2 (car p)))) 'vec))
264 (math-flatten-vector (symbol-value
266 (math-reject-arg (car p) 'numvecp)))))
270 (defun calcFunc-vflat (&rest vecs)
271 (math-flatten-many-vecs vecs))
273 (defun math-split-sdev-vec (vec zero-ok)
274 (let ((means (list 'vec))
278 (while (and (setq p (cdr p))
279 (not (and (consp (car p))
280 (eq (car (car p)) 'sdev)))))
283 (while (setq vec (cdr vec))
284 (if (and (consp (setq p (car vec)))
287 (setq means (cons (nth 1 p) means)
288 wts (cons (nth 2 p) wts)))
290 (setq means (cons (nth 1 p) means)
293 (setq means (list 'vec)
296 (setq means (cons p means)))))
297 (list (nreverse means)
298 (and wts (nreverse wts))))))
301 ;;; Return the arithmetic mean of the argument numbers or vectors.
302 ;;; (If numbers are error forms, computes the weighted mean.)
303 (defun calcFunc-vmean (&rest vecs)
304 (let* ((split (math-split-sdev-vec (math-flatten-many-vecs vecs) nil))
307 (len (1- (length means))))
309 (math-reject-arg nil "*Must be at least 1 argument")
310 (if (and (= len 1) (eq (car-safe (nth 1 means)) 'intv))
311 (let ((x (math-fix-int-intv (nth 1 means))))
312 (calcFunc-vmean (nth 2 x) (nth 3 x)))
313 (math-with-extra-prec 2
314 (if (and wts (> len 1))
315 (let* ((sqrwts (calcFunc-map '(var mul var-mul) wts wts))
316 (suminvsqrwts (calcFunc-reduce
318 (calcFunc-map '(var div var-div)
320 (math-div (calcFunc-reduce '(var add var-add)
321 (calcFunc-map '(var div var-div)
324 (math-div (calcFunc-reduce '(var add var-add) means) len)))))))
326 (defun math-fix-int-intv (x)
330 (if (memq (nth 1 x) '(2 3)) (nth 2 x) (math-add (nth 2 x) 1))
331 (if (memq (nth 1 x) '(1 3)) (nth 3 x) (math-sub (nth 3 x) 1)))))
333 ;;; Compute the mean with an error estimate.
334 (defun calcFunc-vmeane (&rest vecs)
335 (let* ((split (math-split-sdev-vec (math-flatten-many-vecs vecs) nil))
338 (len (1- (length means))))
340 (math-reject-arg nil "*Must be at least 1 argument")
341 (math-with-extra-prec 2
343 (let* ((sqrwts (calcFunc-map '(var mul var-mul) wts wts))
344 (suminvsqrwts (calcFunc-reduce
346 (calcFunc-map '(var div var-div)
349 (math-div (calcFunc-reduce '(var add var-add)
350 (calcFunc-map '(var div var-div)
353 (list 'calcFunc-sqrt (math-div 1 suminvsqrwts))))
354 (let ((mean (math-div (calcFunc-reduce '(var add var-add) means)
359 (math-div (calcFunc-reducer
361 (calcFunc-map '(var pow var-pow)
362 (calcFunc-map '(var abs var-abs)
368 (math-mul len (1- len)))))))))))
371 ;;; Compute the median of a list of values.
372 (defun calcFunc-vmedian (&rest vecs)
373 (let* ((flat (copy-sequence (cdr (math-flatten-many-vecs vecs))))
378 (math-reject-arg nil "*Must be at least 1 argument")
379 (if (and (= len 1) (memq (car-safe (car flat)) '(sdev intv)))
380 (calcFunc-vmean (car flat))
382 (if (eq (car-safe (car p)) 'sdev)
383 (setcar p (nth 1 (car p))))
384 (or (Math-anglep (car p))
385 (math-reject-arg (car p) 'anglep))
387 (setq flat (sort flat 'math-lessp))
389 (math-div (math-add (nth (1- hlen) flat) (nth hlen flat)) 2)
393 (defun calcFunc-vgmean (&rest vecs)
394 (let* ((flat (math-flatten-many-vecs vecs))
395 (len (1- (length flat))))
397 (math-reject-arg nil "*Must be at least 1 argument")
398 (math-with-extra-prec 2
399 (let ((x (calcFunc-reduce '(var mul math-mul) flat)))
402 (math-pow x (list 'frac 1 len))))))))
405 (defun calcFunc-agmean (a b)
406 (cond ((Math-equal a b) a)
409 (calc-symbolic-mode (math-inexact-result))
410 ((not (Math-realp a)) (math-reject-arg a 'realp))
411 ((not (Math-realp b)) (math-reject-arg b 'realp))
413 (math-with-extra-prec 2
414 (setq a (math-float (math-abs a))
415 b (math-float (math-abs b)))
417 (while (not (math-nearly-equal-float a b))
418 (setq mean (math-mul-float (math-add-float a b) '(float 5 -1))
419 b (math-sqrt-float (math-mul-float a b))
424 (defun calcFunc-vhmean (&rest vecs)
425 (let* ((flat (math-flatten-many-vecs vecs))
426 (len (1- (length flat))))
428 (math-reject-arg nil "*Must be at least 1 argument")
429 (math-with-extra-prec 2
431 (calcFunc-reduce '(var add math-add)
432 (calcFunc-map '(var inv var-inv) flat)))))))
436 ;;; Compute the sample variance or standard deviation of numbers or vectors.
437 ;;; (If the numbers are error forms, only the mean part of them is used.)
438 (defun calcFunc-vvar (&rest vecs)
439 (if (and (= (length vecs) 1)
440 (memq (car-safe (car vecs)) '(sdev intv)))
441 (if (eq (car-safe (car vecs)) 'intv)
442 (math-intv-variance (car vecs) nil)
443 (math-sqr (nth 2 (car vecs))))
444 (math-covariance vecs nil nil 0)))
446 (defun calcFunc-vsdev (&rest vecs)
447 (if (and (= (length vecs) 1)
448 (memq (car-safe (car vecs)) '(sdev intv)))
449 (if (eq (car-safe (car vecs)) 'intv)
450 (if (math-floatp (car vecs))
451 (math-div (math-sub (nth 3 (car vecs)) (nth 2 (car vecs)))
453 (math-sqrt (calcFunc-vvar (car vecs))))
455 (math-sqrt (math-covariance vecs nil nil 0))))
457 ;;; Compute the population variance or std deviation of numbers or vectors.
458 (defun calcFunc-vpvar (&rest vecs)
459 (if (and (= (length vecs) 1)
460 (memq (car-safe (car vecs)) '(sdev intv)))
461 (if (eq (car-safe (car vecs)) 'intv)
462 (math-intv-variance (car vecs) t)
463 (math-sqr (nth 2 (car vecs))))
464 (math-covariance vecs nil t 0)))
466 (defun calcFunc-vpsdev (&rest vecs)
467 (if (and (= (length vecs) 1)
468 (memq (car-safe (car vecs)) '(sdev intv)))
469 (if (eq (car-safe (car vecs)) 'intv)
470 (if (math-floatp (car vecs))
471 (math-div (math-sub (nth 3 (car vecs)) (nth 2 (car vecs)))
473 (math-sqrt (calcFunc-vpvar (car vecs))))
475 (math-sqrt (math-covariance vecs nil t 0))))
477 (defun math-intv-variance (x pop)
478 (or (math-constp x) (math-reject-arg x 'constp))
480 (math-div (math-sqr (math-sub (nth 3 x) (nth 2 x))) 12)
481 (let* ((x (math-fix-int-intv x))
482 (len (math-sub (nth 3 x) (nth 2 x)))
483 (hlen (math-quotient len 2)))
484 (math-div (if (math-evenp len)
485 (calcFunc-sum '(^ (var X var-X) 2) '(var X var-X)
486 (math-neg hlen) hlen)
487 (calcFunc-sum '(^ (- (var X var-X) (/ 1 2)) 2)
489 (math-neg hlen) (math-add hlen 1)))
490 (if pop (math-add len 1) len)))))
492 ;;; Compute the covariance and linear correlation coefficient.
493 (defun calcFunc-vcov (vec1 &optional vec2)
494 (math-covariance (list vec1) (list vec2) nil 1))
496 (defun calcFunc-vpcov (vec1 &optional vec2)
497 (math-covariance (list vec1) (list vec2) t 1))
499 (defun calcFunc-vcorr (vec1 &optional vec2)
500 (math-covariance (list vec1) (list vec2) nil 2))
503 (defun math-covariance (vec1 vec2 pop mode)
504 (or (car vec2) (= mode 0)
506 (if (and (eq (car-safe (car vec1)) 'var)
507 (eq (car-safe (calc-var-value (nth 2 (car vec1)))) 'vec))
508 (setq vec1 (symbol-value (nth 2 (car vec1))))
509 (setq vec1 (car vec1)))
510 (or (math-matrixp vec1) (math-dimension-error))
511 (or (= (length (nth 1 vec1)) 3) (math-dimension-error))
512 (setq vec2 (list (math-mat-col vec1 2))
513 vec1 (list (math-mat-col vec1 1)))))
514 (math-with-extra-prec 2
515 (let* ((split1 (math-split-sdev-vec (math-flatten-many-vecs vec1) nil))
516 (means1 (car split1))
517 (wts1 (nth 1 split1))
518 split2 means2 (wts2 nil)
521 (len (1- (length means1))))
522 (if (< len (if pop 1 2))
523 (math-reject-arg nil (if pop
524 "*Must be at least 1 argument"
525 "*Must be at least 2 arguments")))
527 (setq sqrwts (math-add
529 (calcFunc-map '(var mul var-mul) wts1 wts1)
532 (calcFunc-map '(var mul var-mul) wts2 wts2)
534 suminvsqrwts (calcFunc-reduce
536 (calcFunc-map '(var div var-div) 1 sqrwts))))
539 (setq split2 (math-split-sdev-vec (math-flatten-many-vecs vec2)
543 (or (= len (1- (length means2))) (math-dimension-error))))
544 (let* ((diff1 (calcFunc-map
548 (math-div (calcFunc-reduce
550 (calcFunc-map '(var div var-div)
552 (math-neg suminvsqrwts))
553 (math-div (calcFunc-reducer '(var add var-add) means1)
555 (diff2 (if (= mode 0)
561 (math-div (calcFunc-reduce
563 (calcFunc-map '(var div var-div)
565 (math-neg suminvsqrwts))
566 (math-div (calcFunc-reducer '(var add var-add) means2)
568 (covar (calcFunc-map '(var mul var-mul) diff1 diff2)))
570 (setq covar (calcFunc-map '(var div var-div) covar sqrwts)))
572 (calcFunc-reducer '(var add var-add) covar)
574 (let ((var1 (calcFunc-map '(var mul var-mul) diff1 diff1))
575 (var2 (calcFunc-map '(var mul var-mul) diff2 diff2)))
577 (setq var1 (calcFunc-map '(var div var-div) var1 sqrwts)
578 var2 (calcFunc-map '(var div var-div) var2 sqrwts)))
580 (math-mul (calcFunc-reducer '(var add var-add) var1)
581 (calcFunc-reducer '(var add var-add) var2))))
585 (math-div (math-mul suminvsqrwts (1- len)) len))
586 (if pop len (1- len)))))))))
588 ;;; calc-stat.el ends here