share/contrib/diffequations/extrabessel.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 ($put '$extrabessel 1 '$version)
  16
  17 (putprop '$fbessel_j
  18          '((mu x)
  19            ((unk) "$order" "$fbessel_j")
  20            (($dbessel_j) mu x))
  21          'grad)
  22
  23 (putprop '$dbessel_j
  24          '((mu x)
  25            ((unk) "$order" "$dbessel_j")
  26            ((mtimes ) -1 ((mexpt ) x -2)
  27             ((mplus )
  28              ((mtimes )
  29               ((mplus ) ((mtimes ) -1 ((mexpt) mu 2))
  30                ((mexpt  ) x 2))
  31               (($fbessel_j) mu x))
  32              ((mtimes) x (($dbessel_j) mu x)))))
  33          'grad)
  34
  35 (putprop '$fbessel_y
  36          '((mu x)
  37            ((unk) "$order" "$fbessel_y")
  38            (($dbessel_y) mu x))
  39          'grad)
  40
  41 (putprop '$dbessel_y
  42          '((mu x)
  43            ((unk) "$order" "$dbessel_y")
  44            ((mtimes ) -1 ((mexpt ) x -2)
  45             ((mplus )
  46              ((mtimes )
  47               ((mplus ) ((mtimes ) -1 ((mexpt) mu 2))
  48                ((mexpt  ) x 2))
  49               (($fbessel_y) mu x))
  50              ((mtimes) x (($dbessel_y) mu x)))))
  51          'grad)
  52