数组？？

string   r_string=''  
  for   i=1   to   7  
          r_string+=string(rand_num[i])+'   '  
  next  
          mle_1.text=r_string+'     '  
  其中rand_num[i]是一个随机的整数数组，为什么第一个数总是   0   呢？ 问题点数：20、回复次数：5Top

1 楼princelily（百合）回复于 2005-04-07 17:57:29 得分 5

你定义的rand_num[]数组是怎么初始化的，我知道Rand(n)函数是得到1到n之间的一个伪随机数。不知道你是怎么设定随机数的。嘿嘿Top

2 楼zengpeiwen（笑江）回复于 2005-04-07 18:04:14 得分 0

就rand(30)  
   
  假如  
          r_string=string(rand_num[i])+'   '+r_string  
  则是最后一个为0  
  Top

3 楼fibbery（飞)(睡足了才能提高效率）回复于 2005-04-07 18:08:05 得分 5

先使用下面的函数:  
  Description    
   
  Initializes   the   random   number   generator   so   that   the   Rand   function   begins   a   new   series   of   pseudorandom   numbers.  
   
  Syntax    
   
  Randomize   (   n   )  
   
  Argument Description  
  n   The   starting   value   (seed)   for   the   random   number   generator.   When   n   is   0,   PowerBuilder   takes   the   seed   from   the   system   clock   and   begins   a   nonrepeatable   sequence.   A   nonzero   number   generates   a   different   but   repeatable   sequence   for   each   seed   value.   n   cannot   exceed   32,767  
  Return   value    
   
  Integer.   If   n   is   NULL,   Randomize   returns   NULL.   The   return   value   is   never   used.  
   
  Usage    
   
  The   sequence   of   numbers   generated   by   repeated   calls   to   the   Rand   function   is   a   computer-generated   pseudorandom   sequence.   You   can   use   the   Randomize   function   to   initialize   the   random   number   generator   with   a   value   from   the   system   clock,   or   some   other   changing   value,   so   that   the   sequence   is   always   different.   For   testing   purposes,   you   can   select   a   specific   seed   value,   which   you   can   reuse   to   make   the   pseudorandom   sequence   repeatable   each   time   you   run   the   application.  
  Include   Randomize   in   the   script   for   the   Open   event   in   the   application.Top

4 楼fibbery（飞)(睡足了才能提高效率）回复于 2005-04-07 18:10:03 得分 5

先初始化随机数生成器,不然每次使用运行时所获得的随机数是一样的!Top

5 楼jiangxj（）回复于 2005-04-08 09:04:24 得分 5

先设置  
  Randomize   (0)  
  再做你的代码就行了  
   
  Randomize   (0)表示用系统时间初始化随机数,由于时间总在变,故得到的随机数序列也不同Top

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