🚀 go-pugleaf

In article <1iig7aINNtc@spim.mti.sgi.com>, jackc@vermont.mti.sgi.com (Jack Choquette) writes:
|> [...]
|> So it makes more sense, mathematically at least, to reverse number
|> numbers and zero fill the number that are not there.
|> 		digit #		5  4  3  2  1  0
|> 		digit value	0  1, 0  5  6  2
|> 		digit value	7  1, 0  5  6  2
|> 
|> Now we come to representing numbers in computers.  Being mathematically
|> inclined, computer engineers represent numbers by putting the least
|> significant bit in the lowest numbered (and addressible) spot.  Being
|> human, when they print out the number they print out the most significant
|> bit first:
|> 		digit #/address		7  6  5  4  3  2  1  0
|> 		digit value (bin)	0  1  0  0  1  1  1  0   =   78 dec

What Jack fails to note is that some of the early computers (e.g., the
ACE at the NPL in Teddington) stored rational fractions rather than
integers.

Thus it was entirely reasonable (i.e., both from the mathematical and
the engineering point of view) to number the most significant digit
(2**-1 or 10**-1, I don't remember which) as digit 1, the next most as
digit 2, and so on.

Jim Haynes has subsequently highlighted Jack's hypothesis for his
argument of left-to-right reading humans.  In view of who was building
the earliest computers, Jack is right to use that hypothesis, imho.
--
Robin (Keep Radio 3 != Classic FM) Fairbairns       rf@cl.cam.ac.uk
U of Cambridge Computer Lab, Pembroke St, Cambridge  CB2 3QG, UK