share/contrib/diffequations/gauss.lisp

   1 ;; Author Barton Willis
   2 ;; University of Nebraska at Kearney
   3 ;; Copyright (C) 2004, Barton Willis
   4
   5 ;; Brief Description: Maxima code for linear homogeneous second order
   6 ;; differential equations.
   7
   8 ;; Maxima odelin is free software; you can redistribute it and/or
   9 ;; modify it under the terms of the GNU General Public License,
  10 ;; http://www.gnu.org/copyleft/gpl.html.
  11
  12 ;; Maxima odelin has NO WARRANTY, not even the implied warranty of
  13 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  14
  15 ($put '$gauss 1 '$version)
  16
  17 (putprop '$gauss_a
  18          `((a b c x)
  19            ((unk) "$first" "$gauss_a")
  20            ((unk) "$second" "$gauss_a")
  21            ((unk) "$third" "$gauss_a")
  22            (($dgauss_a) a b c x))
  23          'grad)
  24
  25 (putprop '$dgauss_a
  26          `((a b c x)
  27            ((unk) "$first" "$dgauss_a")
  28            ((unk) "$second" "$dgauss_a")
  29            ((unk) "$third" "$dgauss_a")
  30            ((mtimes) ((mexpt) ((mplus) 1 ((mtimes) -1 x)) -1)
  31             ((mexpt) x -1)
  32             ((mplus) ((mtimes) a (($gauss_a) a b c x) b)
  33              ((mtimes) (($dgauss_a) a b c x)
  34               ((mplus) ((mtimes) -1 c)
  35                ((mtimes) ((mplus) 1 a b) x))))))
  36          'grad)
  37
  38 (putprop '$gauss_b
  39          `((a b c x)
  40            ((unk) "$first" "$gauss_b")
  41            ((unk) "$second" "$gauss_b")
  42            ((unk) "$third" "$gauss_b")
  43            (($dgauss_b) a b c x))
  44          'grad)
  45
  46 (putprop '$dgauss_b
  47          `((a b c x)
  48            ((unk) "$first" "$dgauss_b")
  49            ((unk) "$second" "$dgauss_b")
  50            ((unk) "$third" "$dgauss_b")
  51            ((mtimes) ((mexpt) ((mplus) 1 ((mtimes) -1 x)) -1)
  52             ((mexpt) x -1)
  53             ((mplus) ((mtimes) a (($gauss_b) a b c x) b)
  54              ((mtimes) (($dgauss_b) a b c x)
  55               ((mplus) ((mtimes) -1 c)
  56                ((mtimes) ((mplus) 1 a b) x))))))
  57          'grad)