home bbs files messages ]

Forums before death by AOL, social media and spammers... "We can't have nice things"

   sci.math.symbolic      Symbolic algebra discussion      10,432 messages   

[   << oldest   |   < older   |   list   |   newer >   |   newest >>   ]

   Message 9,685 of 10,432   
   clicliclic@freenet.de to Richard Fateman   
   Re: [Axiom] use of Roman numbers   
   06 Nov 17 18:21:43   
   
   Richard Fateman schrieb:   
   >   
   > On 11/5/2017 4:21 AM, clicliclic@freenet.de wrote:   
   > > I don't see why Roman numerals couldn't be handled in the same manner,   
   > Roman numerals are not positional.  So it wouldn't be  "the same manner".   
   > Also, is x*x   x^2, 10*x or 100?   
      
   Using Roman numerals one has x*x = x^ii = c.   
      
   That "Roman numerals are not positional" will affect the conversion   
   algorithms, but does not bear on when to interpret input or display   
   output as Roman numerals.   
      
   A problem is the distinction of Roman numerals from variables, which   
   also arises for non-Roman numerals with base greater ten. In Derive, a   
   hexadecimal number like ace (= 10*16^2 + 12*16 + 14) must be written as   
   0ace to distinguish it from a variable. Thus, with input switched to   
   hexadecimal, ace is interpreted as a variable and 0ice is interpreted   
   as 0*ice (= 0), where ice is again a variable.   
      
   For simplicity, one might use the zero prefix for Roman numerals too;   
   then all variable names would remain valid, and Roman numerals could   
   even be mixed with decimal (or dual or octal) ones, as in your example   
   expressions. Input like 0xxyy should become 0xx*yy (= 20*yy).   
      
   >   
   > > but I doubt that it would it be worth the effort.   
   > For sure. Unless a CAS is used for clock faces or tombstones.   
      
   Exactly.   
      
   Martin.   
      
   PS: Derive actually allows to use any base from 2 to 36, by specifying   
   InputBase := OutputBase := 36 for example. The limit of 36 arises   
   because there are only ten decimal digits plus 26 ASCII letters.   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)   

[   << oldest   |   < older   |   list   |   newer >   |   newest >>   ]


(c) 1994,  bbs@darkrealms.ca