OM Floats : conversion

[Richard J. Fateman]

see http://www.cs.berkeley.edu/~wkahan/ieee754status/ieee754.ps

In fact, if we agree on the ordering of bytes in words (which computers
don't, of course), then the ordering of bits in IEEE format numbers
is specified. So other than big/little endian, maybe we can encode
floats as one or more 32-bit quantities.  How do you want to send
32-bit quantities?  Signed integers? hex strings?  If we agree on
hex character strings, then a double takes exactly 16 characters.
Hex is fairly pointless for this purpose.
If we use all the 127 ASCII printing characters, we get 8 chars
(actually we need only 7 chars+ 1 bit.).

If you want to send doubles as decimal floats, here's a useful fact.
If you start with a decimal number input of 15 digits, then
correct IEEE decimal/binary/decimal conversion must give you
the same 15 digits output.

If you start with a binary number (double) and do binary/decimal/binary
conversion, to guarantee the same binary number, you may need 17 decimal
digits. That's just for the fraction. Not counting exponent, decimal
point, sign etc.  Random floating-point numbers are probably going
to need 21 characters or more.

Cheers.
RJF