关于主元素消去法解多元一次方程的问题

kellyyang1

我写了如下的代码想用主元素消去法解多元一次方程；(defun c:kk()
(setq matrix2 (vlax-make-safearray vlax-vbdouble (cons 1 5)(cons 1 6)))
(setq matrix3 (vlax-make-safearray vlax-vbdouble (cons 1 5)(cons 1 6)))
(setq ll '((10 20 30 40 50 60)
(12 13 21 22 24 30)
(11 4 3 7 9 10)
(9 7 35 67 12 8)
(65 73 28 91 16 28))
)
(vlax-safearray-fill matrix2 ll)
(setq num1 4)
(setq ylen 6)
(setq n4 1)
(repeat num1
(setq n5 n4)
(setq maxa (abs (vlax-safearray-get-element matrix2 n4 n4)))
(setq len1 (- 5 n4))
(setq n6 (1+ n4))
(repeat len1
(if (> (abs (vlax-safearray-get-element matrix2 n6 n4)) maxa)
(progn(setq maxa (abs(vlax-safearray-get-element matrix2 n6 n4)))
(setq n5 n6)
)
(setq n6 (1+ n6))
)
)
(setq n7 1)
(repeat ylen
(setq ass1 (vlax-safearray-get-element matrix2 n4 n7))
(vlax-safearray-put-element matrix2 n4 n7 (vlax-safearray-get-element matrix2 n5 n7))
(vlax-safearray-put-element matrix2 n5 n7 ass1)
(setq n7 (1+ n7))
)
(setq n12 1)
(repeat ylen
(vlax-safearray-put-element matrix3 1 n12 (vlax-safearray-get-element matrix2 1 n12))
(setq n12 (1+ n12))
)
(setq n8 (1+ n4))
(repeat len1
(setq n9 1)
(repeat ylen
(setq ass2 (* (vlax-safearray-get-element matrix2 n4 n9) (vlax-safearray-get-element matrix2 n8 n4)))
(setq ass3 (/ ass2 (vlax-safearray-get-element matrix2 n4 n4)))
(setq ass4 (- (vlax-safearray-get-element matrix2 n8 n9) ass3))
(vlax-safearray-put-element matrix3 n8 n9 ass4)
(setq n9 (1+ n9))
)
(setq n8 (1+ n8))
)
(setq n10 1)
(repeat 5
(setq n11 1)
(repeat ylen
(setq ass5 (vlax-safearray-get-element matrix3 n10 n11))
(vlax-safearray-put-element matrix2 n10 n11 ass5)
(setq n11 (1+ n11))
)
(setq n10 (1+ n10))
)
(setq n4 (1+ n4))
)/////////////////////////////////用主元素消去法求解方程

(setq n1 1)
(repeat 5
(setq n2 1)
(repeat 6
(princ (vlax-safearray-get-element matrix2 n1 n2))
(princ " ")

(setq n2 (1+ n2))
)
(print "\n")
(setq n1 (1+ n1))
)
)可是显示的matrix2数组并不是上三角阵，为什么呢？？拜托各位能看看我的程序，找出原因，谢谢了。

meflying

程序太难理清,把数学过程说一下吧(按你的程序思路说)