Dual precision numbers

Comments

• Bruce Bates Posts: 3,045

  2006-05-14 03:41 edited 2006-05-14 03:41

  Scott -
  
  Here are some double precision math routines which should do the trick, thanks to Dr. Tracy Allen:
  http://www.emesystems.com/BS2math6.htm
  
  Regards,
  
  Bruce Bates
  
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• ScottL Posts: 14

  2006-05-14 04:32 edited 2006-05-14 04:32

  Thanks, looks like that will do the trick. -Scott
• Mike Green Posts: 23,101

  2006-05-14 05:10 edited 2006-05-14 05:10

  If you mostly need to input and output or count or add, you could do binary coded decimal (BCD) with a decimal digit per nibble. The Stamp can access nibbles (4 bits) as arrays storing two decimal digits per byte. A simple loop could add two 8 digit numbers one digit at a time like:
  a var nib(8)
  b var nib(8)
  c var byte
  i var nib
  add:
  c = 0
  for i=0 to 7
  c = a + b + c
  if c >= 10 then carryIt
  a = c : c = 0
  goto fini(expletive)
  carryIt:
  a = c - 10: c = 1
  fini(expletive):
  next
  return
• Mike Green Posts: 23,101

  2006-05-14 05:13 edited 2006-05-14 05:13

  Note that the forum software censored my label f.i.n.i.s.h.I.t [noparse][[/noparse]ignore the periods].
• Mike Green Posts: 23,101

  2006-05-14 05:15 edited 2006-05-14 05:15

  It also removed my 'i' subscripts after the 'a' and 'b' variables. Oh well!
• Jon Williams Posts: 6,491

  2006-05-14 15:02 edited 2006-05-14 15:02

  We've had some unruly teenagers attempting to post foul language in recent months so we've had to enable auditing for "naughty" keywords -- I think Finish_It would have flown through and looks like a valid label (in accordance with "The Elements of PBASIC Style").
  
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  Jon Williams
  Applications Engineer, Parallax
• SSteve Posts: 808

  2006-05-14 19:15 edited 2006-05-14 19:15

  And you would have had better luck with the subscripts if you had enclosed the code in a code tag. Outside of the code tag the i in square brackets turns italics on. That's why some of the code is italicized.
  
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  OS-X: because making Unix user-friendly was easier than debugging Windows
• ScottL Posts: 14

  2006-05-14 21:37 edited 2006-05-14 21:37

  Mike, thanks for the BCD idea. Unfortunately I could not follow your example but I was able to take the idea and make it work. (though not efficiently) -Scott

  bpx

  bpx

  doubleprecision.bpx

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  doubleprecision.bpx 1.3K